Integrated circuits and semiconductor modules

Abstract

To provide a circuit capable of supplying a reference voltage having desired temperature characteristics.SOLUTION: Provided is an integrated circuit including: a first current source; a second current source which is provided in parallel to the first current source; a first resistor whose one end is connected to an output of the first current source; a first bipolar transistor which is connected to the other end of the first resistor and diode-connected; a second bipolar transistor which is connected to an output of the second current source and diode-connected; a second resistor which is connected to the second bipolar transistor; and an output circuit which outputs a third voltage based on a first voltage output from the first current source and a second voltage output from the second current source.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to integrated circuits and semiconductor modules.

Background Art

[0002] A reference voltage circuit using the bandgap voltage of a semiconductor is known (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In a bandgap reference voltage circuit including a bipolar transistor, when the bipolar transistor becomes hot, a leakage current may occur between the N-well region covering the collector terminal and the substrate. Therefore, the current of the current output from the substrate of the reference voltage circuit may increase, and the voltage output from the reference voltage circuit may not have desired temperature characteristics.

[0005] The present invention has been made in view of the above-described conventional problems, and an object thereof is to provide a circuit that can supply a reference voltage having desired temperature characteristics.

Means for Solving the Problems

[0006] To solve the above problems, a first embodiment of the present invention provides an integrated circuit comprising: a first current source; a second current source provided in parallel with the first current source; a first resistor with one end connected to the output of the first current source; a first bipolar transistor connected to the other end of the first resistor and diode-connected; a second bipolar transistor connected to the output of the second current source and diode-connected; a second resistor connected to the second bipolar transistor; and an output circuit that outputs a third voltage based on a first voltage output from the first current source and a second voltage output from the second current source.

[0007] In a second aspect of the present invention, an integrated circuit is provided comprising: a first current source; a second current source provided in parallel with the first current source; a first resistor with one end connected to the output of the first current source; a first bipolar transistor connected to the other end of the first resistor and diode-connected; a plurality of first trimming elements connected to the output of the second current source; a plurality of second bipolar transistors, each connected to the plurality of first trimming elements and diode-connected; a second resistor with one end connected to the plurality of second bipolar transistors; and an output circuit that outputs a third voltage based on a first voltage output from the first current source and a second voltage output from the second current source.

[0008] A third embodiment of the present invention provides a semiconductor module comprising an integrated circuit and a switching element, wherein the integrated circuit includes a control circuit connected to a control electrode of the switching element that controls the driving of the switching element based on an input signal, and the control circuit controls the driving of the switching element based on the input signal and the third voltage. [Effects of the Invention]

[0009] A circuit can be provided that can supply a reference voltage with desired temperature characteristics.

[0010] It should be noted that the above summary of the invention does not enumerate all the necessary features of the present invention. Furthermore, subcombinations of these features may also constitute an invention. [Brief explanation of the drawing]

[0011] [Figure 1] An example of the configuration of the semiconductor module 10 is shown. [Figure 2] An example of a circuit diagram for the voltage generation circuit 41a is shown. [Figure 3] This shows an example of a conceptual diagram illustrating the generation of leakage current Is1 in a bipolar transistor 74. [Figure 4] An example of a schematic diagram showing the temperature dependence of current and voltage in the reference voltage circuit 52a is shown. [Figure 5] An example of the temperature change of voltages V1, V2, and Vref1 is shown. [Figure 6] An example of a circuit diagram for the voltage generation circuit 101a related to the comparative example is shown. [Figure 7] An example of a schematic diagram showing the temperature dependence of current and voltage in the voltage generation circuit 101a is shown. [Figure 8] An example of the configuration of integrated circuit 23c is shown. [Figure 9] An example of the configuration of the reference voltage circuit 52c is shown. [Figure 10] An example of the reference voltage Vref1 output by the reference voltage circuit 52c is shown. [Figure 11] An example of the reference voltage Vref1 when the number of switches 124a to 124m in the ON state is changed is shown. [Figure 12] An example of the reference voltage Vref1 when the number of switches 133a to 133n in the ON state is changed is shown. [Figure 13] An example of the trimming flow performed in the reference voltage circuit 52c is shown. [Modes for carrying out the invention]

[0012] Hereinafter, the present invention will be described through embodiments of the invention. However, the following embodiments do not limit the invention claimed in the claims. Also, not all combinations of features described in the embodiments are essential for the solution of the invention.

[0013] In this specification, the term "connection" is used, and unless otherwise specified, "connection" shall mean "electrically connected".

[0014] ===Example === <<Configuration example of semiconductor module 10>> FIG. 1 shows an example of the configuration of a semiconductor module 10. The semiconductor module 10 is a module for driving a load 11 based on an instruction from a microcomputer (not shown) provided externally.

[0015] The semiconductor module 10 uses a power supply 12 provided externally and supplying a voltage HV as a main power supply for power conversion with respect to the load 11. The semiconductor module 10 includes semiconductor chips 21a, 21b, power supplies 22a, 22b, and integrated circuits 23a, 23b.

[0016] The semiconductor module 10 of the present embodiment is an IPM (Intelligent Power Module) in which the semiconductor chips 21a, 21b and the integrated circuits 23a, 23b having a driving function and various protection functions of the circuits of the semiconductor chips 21a, 21b are packaged in one package.

[0017] Here, among the chips and the like constituting the semiconductor module 10, the semiconductor chip 21a, the power supply 22a, and the integrated circuit 23a are provided on the low side, and the semiconductor chip 21b, the power supply 22b, and the integrated circuit 23b are provided on the high side. Also, in the present embodiment, since the configuration of the circuit on the low side and the configuration of the circuit on the high side are the same, the circuit on the low side will be mainly described below.

[0013]

[0014]

[0015]

[0016]

[0017]

[0018] [[ID=]] The load 11 is, for example, a motor coil, and is driven by a voltage Vout output from a contact node located between semiconductor chips 21a and 21b.

[0019] The semiconductor chip 21a includes a switching element for driving the load 11 and a temperature sensing element. In this embodiment, the semiconductor chip 21a includes an IGBT (Insulated Gate Bipolar Transistor) 31a as the switching element and a diode 32a for the IGBT 31a as the temperature sensing element.

[0020] However, the switching element provided on the semiconductor chip 21a is not limited to IGBT 31a; the switching element may be a MOS transistor or a bipolar transistor. Furthermore, the semiconductor chip 21a may include a diode for commutating load current, such as a FWD (Free Wheeling Diode), in addition to the diode 32a.

[0021] Power supply 22a is a power supply for the integrated circuit 23a and applies a power supply voltage Vdd1 to the power supply line L1a. In this embodiment, power supply 22a is provided outside the semiconductor module 10. However, the voltage supplied to the integrated circuit 23a may be generated by a power supply circuit (not shown) provided inside the semiconductor module 10.

[0022] The integrated circuit 23a is a low-voltage integrated circuit (LVIC) that controls the IGBT 31a by outputting a drive signal LO to the gate electrode of the IGBT 31a based on a signal LIN input from a microcontroller (not shown). The integrated circuit 23a includes a voltage generation circuit 41a, a temperature detection circuit 42a, and a control circuit 43a.

[0023] The voltage generation circuit 41a of this embodiment is a circuit that generates a reference voltage Vref1 based on the power supply voltage Vdd1 of the power supply line L1a. The voltage generation circuit 41a includes a temperature compensation circuit 51a and a reference voltage circuit 52a.

[0024] The temperature compensation circuit 51a of this embodiment is a circuit that includes a bipolar element. As will be described later, in a bipolar element, leakage current toward ground occurs in a temperature range above a predetermined temperature.

[0025] The temperature compensation circuit 51a supplies a constant voltage to the reference voltage circuit 52a when the temperature is below a predetermined temperature, and supplies a voltage that decreases according to the temperature when the temperature is above the predetermined temperature. In the temperature compensation circuit 51a and the reference voltage circuit 52a, as will be described later, if leakage current occurs in the bipolar element included in the temperature compensation circuit 51a, the voltage supplied from the temperature compensation circuit 51a to the reference voltage circuit 52a decreases.

[0026] The temperature compensation circuit 51a is connected to the power line L1a and, when voltage is supplied from the power supply 22a, supplies temperature-compensated voltage and current to the reference voltage circuit 52a.

[0027] The reference voltage circuit 52a supplies a reference voltage Vref1 to the control circuit 43a based on the power supply voltage Vdd1 supplied from the power supply line L1a and the voltage and current supplied from the temperature compensation circuit 51a.

[0028] The temperature detection circuit 42a supplies a predetermined current to the diode 32a and outputs a temperature sense signal Tsns1 corresponding to the temperature of the IGBT 31a to the control circuit 43a based on the forward voltage of the diode 32a.

[0029] The control circuit 43a controls the operation of the IGBT31a based on the signal LIN, reference voltage Vref1, and temperature sense signal Tsns1 input from the microcontroller (not shown).

[0030] The control circuit 43a is connected to the control electrode of the switching element of the semiconductor chip 21a. That is, when the switching element is an IGBT 31a, as in this embodiment, it is connected to the gate electrode. Similarly, when the switching element is a MOS transistor, the control circuit 43a is connected to the gate electrode, and when the switching element is a bipolar transistor, the control circuit 43a is connected to the base electrode.

[0031] Specifically, the control circuit 43a controls the driving of the IGBT 31a by outputting a drive signal LO based on the signal LIN. The control circuit 43a also detects overheating of the semiconductor chip 21a based on a reference voltage Vref1 and a temperature sense signal Tsns1. If overheating of the semiconductor chip 21a is detected, the control circuit 43a protects the IGBT 31a from heat, for example, by turning off the IGBT 31a.

[0032] In the corresponding configuration on the high-side, the semiconductor chip 21b comprises an IGBT 31b and a diode 32b, and the power supply 22b applies the power supply voltage Vdd2 to the power supply line L1b. The integrated circuit 23b comprises a voltage generation circuit 41b, a temperature detection circuit 42b, and a control circuit 43b.

[0033] The voltage generation circuit 41b, like the voltage generation circuit 41a, supplies a reference voltage Vref2 to the control circuit 43b, and the temperature detection circuit 42b, like the temperature detection circuit 42a, outputs a temperature sense signal Tsns2 to the control circuit 43b based on the forward voltage of the diode 32b, corresponding to the temperature of the IGBT 31b.

[0034] The control circuit 43b controls the operation of the IGBT31b based on the signal HIN from the microcontroller (not shown), the reference voltage Vref2, and the temperature sense signal Tsns2. The control circuit 43b includes a level conversion circuit (not shown) that converts the signal HIN, whose reference voltage is GND, into a signal whose reference voltage is Vout.

[0035] Thus, the voltage generation circuit 41b and the temperature detection circuit 42b each have the same functions and configuration as the voltage generation circuit 41a and the temperature detection circuit 42a. Therefore, the integrated circuit 23b, which includes the high-side voltage generation circuit 41b, temperature detection circuit 42b, and control circuit 43b, will not be described below.

[0036] Note that the reference voltage Vref1 corresponds to the "third voltage." Also, the control circuit 43b corresponds to the "second control circuit." The reference voltage circuit 52a, which outputs the reference voltage Vref1, will be explained in detail below.

[0037] ===Configuration of Voltage Generation Circuit 41a=== Figure 2 shows an example of a circuit diagram of the voltage generation circuit 41a. The configuration of the temperature compensation circuit 51a and the reference voltage circuit 52a included in the voltage generation circuit 41a is shown.

[0038] The temperature compensation circuit 51a includes MOS transistors 61-64, bipolar transistors 65 and 67, and a resistor 66. MOS transistors 61 and 62 are P-type MOS transistors, while MOS transistors 63 and 64 are N-type MOS transistors.

[0039] The reference voltage circuit 52a comprises MOS transistors 71 and 72, resistors 73 and 76, bipolar transistors 74 and 75, and an output circuit 77. Note that MOS transistors 71 and 72 are P-type MOS transistors.

[0040] <<Configuration of temperature compensation circuit 51a>> In MOS transistors 62 and 63, the gate electrode and drain electrode are diode-connected. MOS transistors 61 and 62 constitute a P-channel current mirror circuit 68, and MOS transistors 63 and 64 constitute an N-channel current mirror circuit 69.

[0041] When voltage Vdd1 and current are supplied from power line L1a to diode-connected MOS transistor 62, MOS transistor 61 turns on. As a result, MOS transistor 61 outputs current based on the current flowing through MOS transistor 62. Consequently, MOS transistors 61 and 62 supply current to MOS transistors 63 and 64, respectively.

[0042] In this embodiment, the drain electrode of MOS transistor 62 is connected to MOS transistor 64, and the gate electrodes of MOS transistors 71 and 72 are connected in parallel. That is, MOS transistor 62 and MOS transistors 71 and 72 constitute a current mirror circuit.

[0043] Here, if no current leakage occurs in the gate electrodes of MOS transistors 71 and 72, the steady-state current flowing from MOS transistor 62 to MOS transistors 71 and 72 can be almost ignored. Therefore, the current supplied from power line L1a to MOS transistors 61 and 62 is supplied to MOS transistors 63 and 64.

[0044] Furthermore, when current is supplied to the diode-connected MOS transistor 63 from the MOS transistor 61 of the current mirror circuit 68, the MOS transistor 64 turns on. As a result, the MOS transistor 64 outputs a current based on the current flowing through the MOS transistor 63. Consequently, the MOS transistor 63 supplies current to the bipolar transistor 65, and the MOS transistor 64 supplies current to the resistor 66.

[0045] In this embodiment, the sizes of MOS transistors 61 and 62 are equal, and the sizes of MOS transistors 63 and 64 are equal. Therefore, the current output from MOS transistors 63 and 64 of the current mirror circuit 69 is equal.

[0046] The base electrode of the bipolar transistor 65 is connected to the collector electrode. In this case, both the base electrode and collector electrode of the bipolar transistor 65 are connected to the source electrode of the MOS transistor 63, which is one end of the output of the current mirror circuit 69. On the other hand, the emitter electrode of the bipolar transistor 65 is grounded.

[0047] One end of resistor 66 is connected to the source electrode of MOS transistor 64, which is the other end of the output of current mirror circuit 69. On the other hand, the other end of resistor 66 is connected to the base electrode and collector electrode of bipolar transistor 67.

[0048] Similar to bipolar transistor 65, the base electrode of bipolar transistor 67 is connected to the collector electrode. On the other hand, the emitter electrode of bipolar transistor 67 is grounded.

[0049] The bipolar transistors 65 and 67 are configured to have different base-emitter voltages. Specifically, in this embodiment, bipolar transistor 65 is composed of a single bipolar transistor, while bipolar transistor 67 consists of multiple bipolar transistors connected in parallel. Therefore, the base-emitter voltage of bipolar transistor 65 is greater than the base-emitter voltage of bipolar transistor 67. Note that the base-emitter voltages of bipolar transistors 65 and 67 both have a positive temperature coefficient.

[0050] In this embodiment, since the currents from the current mirror circuits 68 and 69 are equal, the voltages generated at the respective source electrodes of the MOS transistors 63 and 64 are also equal. Therefore, a voltage with a negative temperature coefficient is generated across resistor 66, depending on the difference between the base-emitter voltage of bipolar transistor 65 and the base-emitter voltage of bipolar transistor 67.

[0051] As a result, the node to which the MOS transistor 64 and resistor 66 are connected generates a voltage that is the sum of the base-emitter voltage of the bipolar transistor 67, which has a positive temperature coefficient, and the voltage across the resistor 66, which has a negative temperature coefficient. In this embodiment, for example, the resistance value of the resistor 66 and the number of bipolar transistors 67 are adjusted so that the temperature coefficient of the voltage at the node to which the MOS transistor 64 and resistor 66 are connected becomes zero.

[0052] Here, a current Iref flows through the bipolar transistor 67. In this embodiment, as the current Iref flowing through the bipolar transistor 67 increases, the voltage supplied from the MOS transistor 62 to the gate electrodes of the MOS transistors 71 and 72 decreases.

[0053] As will be described later with reference to Figures 3 and 4, when the bipolar transistors 65 and 67 rise to a temperature above a predetermined temperature threshold Tth, leakage current is generated in the bipolar transistors 65 and 67. In this case, the current flowing through bipolar transistor 65 and the current Iref flowing through bipolar transistor 67 increase.

[0054] The current flowing through bipolar transistors 65 and 67 is the current supplied to bipolar transistors 65 and 67 from current mirror circuits 68 and 69. Therefore, when leakage current occurs, the current flowing through current mirror circuits 68 and 69 increases.

[0055] The MOS transistors 61 and 62 that constitute the current mirror circuit 68 are P-type MOS transistors. Therefore, when the current flowing through the current mirror circuit 68 increases, the source-drain current of the P-type MOS transistors 61 and 62 increases, and the gate voltage of the MOS transistors 61 and 62 decreases.

[0056] In this case, the gate electrodes of MOS transistors 71 and 72 are connected in parallel to the gate electrode of MOS transistor 62. Therefore, when the gate voltage of MOS transistor 62 decreases, the voltage applied by the temperature compensation circuit 51a to the gate electrodes of MOS transistors 71 and 72 also decreases.

[0057] In other words, the MOS transistor 62 uses the current Iref flowing through the bipolar transistor 67 as a reference current and applies a voltage corresponding to the reference current to the MOS transistors 71 and 72.

[0058] Here, current mirror circuit 68 corresponds to the "first current mirror circuit." Similarly, current mirror circuit 69 corresponds to the "second current mirror circuit."

[0059] Furthermore, resistor 66 corresponds to the "fifth resistor." Bipolar transistor 65 corresponds to the "fourth bipolar transistor," and bipolar transistor 67 corresponds to the "third bipolar transistor." The current Iref flowing through bipolar transistor 67 corresponds to the "reference current." Note that in a bipolar transistor, connecting the base electrode and the collector electrode is equivalent to "diode connection" of the bipolar transistor.

[0060] <<Configuration of Reference Voltage Circuit 52a>> The source electrodes of MOS transistors 71 and 72 are connected in parallel to the power supply line L1a. That is, an equal voltage is applied to the source electrodes of MOS transistors 71 and 72 from the power supply line L1a.

[0061] On the other hand, the gate electrodes of MOS transistors 71 and 72 are connected to the gate electrode of MOS transistor 62. Therefore, MOS transistors 71 and 72, together with MOS transistor 62, form a current mirror circuit, and a predetermined voltage is applied to the gate electrodes of MOS transistors 71 and 72 from the temperature compensation circuit 51a. In this case, each of MOS transistors 71 and 72 functions as a current source that supplies current to the element connected to its drain electrode.

[0062] Furthermore, the MOS transistors 71 and 72 in this embodiment are of equal size. Therefore, the current supplied from the drain electrodes of MOS transistors 71 and 72 is equal.

[0063] One end of resistor 73 is connected to the drain electrode of MOS transistor 71. The other end of resistor 73 is connected to the collector electrode of bipolar transistor 74. Therefore, the current Ic1 supplied from MOS transistor 71 to resistor 73 flows through resistor 73 and is supplied to bipolar transistor 74.

[0064] A current Ic1 flows into the bipolar transistor 74 from the resistor 73. In the bipolar transistor 74, the collector electrode and the base electrode are connected by a diode. That is, the current Ic1 is the current flowing from the collector electrode side to the collector electrode and base electrode of the bipolar transistor 74.

[0065] As will be described later with reference to Figure 3, the P-base region of the bipolar transistor 74 is grounded, and in the bipolar transistor 74, at temperatures above a predetermined temperature, a leakage current Is1 is generated that flows from the substrate towards ground without passing through the emitter electrode.

[0066] Therefore, the current Ic1 can be expressed as the sum of the current Ie flowing out from the emitter electrode of the bipolar transistor 74 and the leakage current Is1 flowing out from the substrate. That is, the equation Ic1 = Ie1 + Is1 holds true.

[0067] Since the current flowing through resistor 73 is current Ic1, the following equation holds for the voltage V1 supplied from the drain electrode of MOS transistor 71: V1 = (Ie1 + Is1) × (resistance of resistor 73) + (voltage drop across bipolar transistor 74). Therefore, the voltage V1 increases as the leakage current Is1 increases.

[0068] On the other hand, the bipolar transistor 75, whose base electrode and collector electrode are diode-connected, receives a current Ic2 from the MOS transistor 72. That is, the current Ic2 is the current flowing into the collector electrode and base electrode of the bipolar transistor 75. The bipolar transistor 75 is connected to the drain electrode of the MOS transistor 72.

[0069] In the bipolar transistor 75, as with the bipolar transistor 74, a leakage current Is2 is generated above a predetermined temperature, which flows from the substrate towards ground without passing through the emitter electrode. As the leakage current Is2 increases, the current Ie2 flowing out from the emitter electrode of the bipolar transistor 75 decreases.

[0070] Resistor 76 has one end connected to the emitter electrode of bipolar transistor 75 and the other end connected to ground. In this case, the voltage drop across resistor 76 is (resistance value of resistor 76) × ie2. In this embodiment, the resistance value of resistor 76 is set to be equal to the resistance value of resistor 73.

[0071] For the voltage V2 supplied by the MOS transistor 72, the following equation holds: V2 = (resistance of resistor 76) × Ie2 + (voltage drop across bipolar transistor 75). Since the current Ie2 decreases as the leakage current Is2 increases, the voltage V2 decreases as the leakage current Is2 increases.

[0072] The current Ic1 supplied by MOS transistors 71 and 72 increases with temperature rise in the temperature range where the bipolar transistor 67 is above a predetermined temperature threshold Tth. Depending on the current Iref flowing through the bipolar transistor 67, the current flowing between the source and drain of the P-type MOS transistor 62 increases, and the gate voltage of the MOS transistor 62 decreases.

[0073] MOS transistors 71 and 72 form a current mirror circuit with MOS transistor 62. Therefore, as the gate voltage of MOS transistor 62 decreases, the gate voltages of P-type MOS transistors 71 and 72 also decrease. As a result, the currents Ic1 and Ic2 flowing between the source and drain of MOS transistors 71 and 72 also increase.

[0074] In other words, in this embodiment, when the bipolar transistor 67 is used as the reference current, the MOS transistors 71 and 72 function as current sources that generate the currents Ic1 and Ic2 supplied from the drain electrode.

[0075] The output circuit 77 outputs a reference voltage Vref1 based on the voltages V1 and V2 supplied from the MOS transistors 71 and 72, which function as current sources.

[0076] In this embodiment, the output circuit 77 includes resistors 81 and 82. That is, the output circuit 77 in this embodiment is a voltage divider circuit composed of resistor 81 connected to the node where voltage V1 is generated and resistor 82 connected to the node where voltage V2 is generated. In this embodiment, the resistance values ​​of resistors 81 and 82 are set to be equal.

[0077] One end of resistor 81 is connected to the drain electrode of MOS transistor 71, which functions as a current source. On the other hand, one end of resistor 82 is connected to the drain electrode of MOS transistor 72, which also functions as a current source.

[0078] The other end of resistor 82 is connected to the side opposite to the side where resistor 81 is connected to the drain electrode of MOS transistor 71. In this case, the output circuit 77 outputs the voltage generated at the node connecting resistors 81 and 82 as the reference voltage Vref1.

[0079] In another embodiment, the output circuit 77 may be an adder circuit that includes, for example, an operational amplifier and adds voltages V1 and V2 to output a reference voltage Vref1. In this case, the output circuit 77 is a non-inverting adder circuit.

[0080] A non-inverting summing circuit can be constructed, for example, by connecting an op-amp to its inverting input and output terminals with a resistor in between, and grounding the inverting input terminal via another resistor to form a so-called non-inverting amplifier circuit, and then connecting resistors 81 and 82 in parallel to the non-inverting input terminal.

[0081] However, the output circuit 77 may be an inverting summing circuit in which resistors 81 and 82 are connected in parallel to the non-inverting input terminals of an inverting amplifier circuit, or it may be a non-inverting summing circuit constructed by connecting an inverting amplifier circuit to an inverting summing circuit.

[0082] On the other hand, in the embodiment where the output circuit 77 in the figure is a voltage divider, the voltages V1 and V2 can be divided using only two resistors, 81 and 82, without using elements such as an operational amplifier. Therefore, the reference voltage circuit 52a of this embodiment can output a reference voltage Vref1 by combining the voltages V1 and V2 with a desired weighting based on the resistance values ​​of resistors 81 and 82, using a circuit with a small circuit area and a small number of circuit components.

[0083] Here, MOS transistor 71 functions as the "first current source" and corresponds to the "first MOS transistor." Similarly, MOS transistor 72 functions as the "second current source" and corresponds to the "second MOS transistor." Voltage V1 corresponds to the "first voltage," and voltage V2 corresponds to the "second voltage."

[0084] Furthermore, resistor 73 corresponds to the "first resistor," and bipolar transistor 74 corresponds to the "first bipolar transistor." Bipolar transistor 75 corresponds to the "second bipolar transistor," and resistor 76 corresponds to the "second resistor." Also, resistor 81 corresponds to the "third resistor," and resistor 82 corresponds to the "fourth resistor."

[0085] ===Mechanism of Leakage Current Is Generation=== Figure 3 shows an example of a conceptual diagram of the generation of leakage current Is1 in the bipolar transistor 74 of the reference voltage circuit 52a. In this embodiment, a bipolar transistor 74 is formed by providing an N-well region 92 in the substrate 91 within the semiconductor, and providing dopant diffusion regions for each terminal to function within the N-well region 92. In this embodiment, the substrate 91 has a P-type conductivity.

[0086] An N+ collector region 93 is provided around the region where the collector terminal 96 is located within the N well region 92, and a P+ base region 94 is provided around the region where the base terminal 97 is located. Furthermore, within the P+ base region 94, an N+ emitter region 95 is provided around the region where the emitter terminal 98 is located.

[0087] In each conductive type, within the designated area, a "+" indicates a higher doping concentration than the area without a "+", while a "-" indicates a lower doping concentration than the area without a "-".

[0088] In such a bipolar transistor 74, the surface area of ​​the PN junction between the substrate 91 and the N-well region 92 is larger compared to a MOS transistor. Furthermore, when the semiconductor device becomes hot, the larger the surface area of ​​the PN junction, the greater the possibility of leakage current Is1 occurring.

[0089] Furthermore, while the mechanism for generating the leakage current Is1 of the bipolar element in the reference voltage circuit 52a was explained using the bipolar transistor 74 as an example, a similar mechanism may also cause a leakage current Is2 to be generated in the bipolar transistor 75.

[0090] Here, the magnitudes of the leakage currents Is1 and Is2 of bipolar transistors 74 and 75 depend on the surface area of ​​the internal PN junction. In bipolar transistors 74 and 75, the magnitudes of the leakage currents Is1 and Is2 can be adjusted to be equal by making the current supplied to each bipolar transistor equal, and by making the number of parallel bipolar transistors constituting each bipolar transistor, as well as the surface area of ​​the PN junction, equal.

[0091] In this embodiment, the bipolar transistors 74 and 75 are of equal size. Furthermore, in this embodiment, the current supplied from the drain electrodes of the MOS transistors 71 and 72 is equal. Therefore, the magnitudes of the leakage currents Is1 and Is2 generated in each of the bipolar transistors 74 and 75 are also adjusted to be equal.

[0092] In this embodiment, "the bipolar transistors 74 and 75 are of equal size" means that the number of parallel bipolar transistors constituting the internal structure is also adjusted so that the overall size of the bipolar transistors is equal.

[0093] Thus, in this embodiment, "leakage current" refers to, for example, the current that flows from the N-well region 92 when a bipolar transistor is formed to the substrate 91.

[0094] ===Temperature Characteristics of Voltage and Current in Reference Voltage Circuit 52a=== Figure 4 shows an example of a schematic diagram of the temperature dependence of current and voltage in the reference voltage circuit 52a. The horizontal axis represents temperature, and the schematics of voltages Vdd1, V1, V2, Vref1 and currents Ic1, Ic2, Ie1, Ie2 are shown. In this embodiment, the graph is shown assuming that leakage current occurs in bipolar transistors 74 and 75 when the temperature exceeds a predetermined temperature threshold Tth.

[0095] The voltage Vdd1 is supplied from power supply 22a via power line L1a. In this embodiment, the voltage Vdd1 is not affected by temperature changes.

[0096] The current Ic1 supplied by MOS transistor 71 and the current Ic2 supplied by MOS transistor 72 increase as the current flowing through the bipolar transistors 65 and 67 of the temperature compensation circuit 51a increases. When leakage current occurs in bipolar transistors 65 and 67, leakage currents Is1 and Is2 also occur in bipolar transistors 74 and 75.

[0097] Therefore, in the temperature range above a predetermined temperature threshold Tth, the currents Ic1 and Ic2 increase with increasing leakage currents Is1 and Is2. In this embodiment, the size of bipolar transistor 74 and the size of bipolar transistor 75 are equal. Therefore, the leakage currents Is1 and Is2 satisfy the equation Is1 = Is2 and increase at an equal rate.

[0098] On the other hand, the current Ie1 flowing out from the emitter electrode of bipolar transistor 74 and the current Ie2 flowing out from the emitter electrode of bipolar transistor 75 decrease as the leakage currents Is1 and Is2 increase.

[0099] Here, voltage V1 satisfies the equation V1 = (Ie1 + Is1) × (resistance of resistor 73) + (voltage drop across bipolar transistor 74), and voltage V2 satisfies the equation V2 = (resistance of resistor 76) × Ie2 + (voltage drop across bipolar transistor 75). In this case, voltage V1 increases with increasing leakage current Is1, and voltage V2 decreases with increasing leakage current Is2.

[0100] Here, since the collector and base electrodes of bipolar transistors 74 and 75 are connected, the voltage drop across bipolar transistors 74 and 75 is equal to the forward voltage of the diode. As an example, the voltage drop across bipolar transistors 74 and 75 is 0.7V. Since the size of bipolar transistor 74 and bipolar transistor 75 are equal, the voltage drops across bipolar transistors 74 and 75 are also approximately the same.

[0101] Furthermore, in this embodiment, the resistance value of resistor 73 and the resistance value of resistor 76 are equal. Therefore, the absolute values ​​of the increase in voltage V1 in bipolar transistor 74 and the decrease in voltage V2 in bipolar transistor 75 that occur with rising temperature can be made approximately the same.

[0102] In this embodiment, resistors 81 and 82 are equal. Therefore, the reference voltage Vref1 is the voltage obtained by equally dividing voltages V1 and V2. In this embodiment, since the increase in voltage V1 and the decrease in voltage V2 are approximately the same, the graph of the reference voltage Vref1 is approximately flat with respect to temperature changes.

[0103] Therefore, in this embodiment, a small-scale reference voltage circuit 52a with a small circuit area and using fewer circuit components can generate a stable reference voltage Vref1 even when the voltage generation circuit 41a becomes hot.

[0104] Furthermore, for example, if the output circuit 77 is a voltage divider circuit, the voltage division ratio of voltages V1 and V2 can be biased by intentionally biasing the ratio of the resistance values ​​of resistors 81 and 82. In that case, the reference voltage circuit 52a of this embodiment can bias the temperature characteristics of the output reference voltage Vref1 to a desired characteristic.

[0105] This makes it possible to provide a circuit that does not experience delays in operation, for example, when the circuit downstream of the voltage generation circuit 41a has temperature characteristics such that the delay time increases at high temperatures if the reference voltage Vref1 remains constant, by providing a positive temperature bias in the reference voltage Vref1.

[0106] Thus, according to the reference voltage circuit 52a of this embodiment, by adjusting the resistance values ​​of resistors 81 and 82 in the voltage divider circuit, the resistance values ​​of resistors 73 and 76, the sizes of bipolar transistors 74 and 75, and the sizes of MOS transistors 71 and 72, a reference voltage Vref1 with desired temperature characteristics can be output.

[0107] Furthermore, in this embodiment, the influence of leakage currents Is1 and Is2 on the reference voltage Vref1 can be adjusted by the configuration of the reference voltage circuit 52a. Therefore, the influence of leakage currents Is1 and Is2 on the reference voltage Vref1 can be adjusted without additional processes such as providing an isolation region around the PN junction region of bipolar transistors 74 and 75 to prevent the generation of leakage currents Is1 and Is2.

[0108] Therefore, according to this embodiment, the effects of leakage currents Is1 and Is2 can be adjusted without increasing the number of steps in the semiconductor process. In other words, the reference voltage circuit 52a of this embodiment also contributes to reducing manufacturing costs.

[0109] Furthermore, in the high-side voltage generation circuit 41b, by providing a temperature compensation circuit 51b and a reference voltage circuit 52b with the same configuration as the voltage generation circuit 41a in this embodiment, it is possible to output a reference voltage Vref2 with a desired temperature specification.

[0110] <<Regarding the parallel configuration of the temperature compensation circuit 51a and the reference voltage circuit 52a>> Here, an increase in currents Ic1 and Ic2 means that the current flowing out from the drain electrodes of MOS transistors 71 and 72 increases. Since MOS transistors 71 and 72 are P-type MOS transistors, the current flowing out from the drain electrodes increases when the gate voltage of MOS transistors 71 and 72 decreases.

[0111] On the other hand, in the temperature range above the temperature threshold Tth, leakage current also occurs in the bipolar transistors 65 and 67 of the temperature compensation circuit 51a. In this case, the current flowing through the current mirror circuits 68 and 69 also increases.

[0112] Since the MOS transistors 61 and 62 that constitute the current mirror circuit 68 are PMOS transistors, the gate voltages of the MOS transistors 61 and 62 decrease as the current in the current mirror circuit 68 increases.

[0113] In this embodiment, the gate electrodes of the MOS transistors 61 and 62 of the current mirror circuit 68 in the temperature compensation circuit 51a are connected in parallel with the gate electrodes of the MOS transistors 71 and 72. Therefore, when the gate voltages of the MOS transistors 71 and 72 in the reference voltage circuit 52a decrease due to the leakage currents Is1 and Is2 of the bipolar transistors 74 and 75, the reduced voltage is also supplied from the temperature compensation circuit 51a.

[0114] In other words, the MOS transistor 62 of the temperature compensation circuit 51a functions as a bias voltage source that supplies a bias voltage corresponding to the current flowing through the bipolar transistors 65 and 67 to the respective gate electrodes of the MOS transistors 71 and 72.

[0115] As a result, in this embodiment, currents Ic1 and Ic2 increase along with the increase in leakage currents Is1 and Is2. Consequently, the output of the reference voltage Vref1 of the reference voltage circuit 52a can be stabilized.

[0116] Figure 5 shows an example of the temperature dependence of voltages V1, V2, and Vref1. In the figure, voltage V1 is represented by a dashed line and voltage V2 is represented by a dashed line.

[0117] In this embodiment, by adjusting the resistance values ​​of resistors 73 and 76, the sizes of bipolar transistors 74 and 75, and the sizes of MOS transistors 71 and 72, the increase in voltage V1 and the decrease in voltage V2 in the range above the temperature threshold Tth are adjusted to be equal.

[0118] Furthermore, in this embodiment, the resistance values ​​of resistors 81 and 82 in the voltage divider circuit are made equal, thereby adjusting the output of the reference voltage Vref1 to be approximately flat. In this way, the reference voltage circuit 52a can output a reference voltage Vref1 with improved temperature characteristics at high temperatures.

[0119] ===Comparative Example=== Figure 6 shows an example of a circuit diagram of a voltage generation circuit 101a related to a comparative example. The voltage generation circuit 101a is connected within the semiconductor module in the same manner as the voltage generation circuit 41a.

[0120] The voltage generation circuit 101a includes a temperature compensation circuit 51a and a reference voltage circuit 111a. The temperature compensation circuit 51a is the same as the circuit included in the voltage generation circuit 41a, while the reference voltage circuit 111a has a different configuration from the reference voltage circuit 52a. In the following, we will mainly focus on the configuration differences between the voltage generation circuit 41a and the voltage generation circuit 101a.

[0121] Unlike the reference voltage circuit 52a, the reference voltage circuit 111a does not have a line containing the MOS transistor 72, the bipolar transistor 75, and the resistor 76. Therefore, the reference voltage circuit 111a does not include a node where voltage V2 is generated, nor does it include a resistor 82 for dividing voltage V2.

[0122] Similar to the reference voltage circuit 52a, a leakage current Is1 is generated in the bipolar transistor 74 by the mechanism shown in Figure 3. As the leakage current Is1 is generated, the current Ic1 also increases.

[0123] In the comparative example as well, the voltage V1 satisfies the formula V1 = (Ie1 + Is1) × (resistance of resistor 73) + (voltage drop across bipolar transistor 74). In the comparative example, since resistor 82 is not included in the reference voltage circuit 111a, the reference voltage Vref1 supplied by the reference voltage circuit 111a is given as the voltage V1 minus the voltage drop across resistor 81.

[0124] ===Temperature Characteristics of Voltage and Current in Reference Voltage Circuit 111a=== Figure 7 shows an example of a schematic diagram of the temperature dependence of current and voltage in the voltage generation circuit 101a of a comparative example. The horizontal axis represents temperature, and the schematics of voltage Vdd1, V1, Vref1, and current Ic1 are shown.

[0125] In the comparative example, as with Vdd1 in Figure 4, the voltage Vdd1 is not affected by temperature changes.

[0126] In the comparative example as well, leakage current Is1 is generated by the mechanism shown in Figure 3 in the temperature range above the temperature threshold Tth. In this case, current Ic1 increases with increasing leakage current Is1.

[0127] The voltage V1 satisfies the equation V1 = (Ie1 + Is1) × (resistance of resistor 73) + (voltage drop across bipolar transistor 74). Therefore, as the leakage current Is1 increases, the voltage V1 rises.

[0128] In the comparative example reference voltage circuit 111a, there is no node that generates a voltage V2 that cancels out the effect of the rise in voltage V1. The reference voltage Vref1 output by the reference voltage circuit 111a is the voltage obtained by subtracting the voltage drop due to the resistor 81 from the voltage V1, so as the voltage V1 rises, the reference voltage Vref1 output by the reference voltage circuit 111a also rises.

[0129] As described above, in the comparative example, the reference voltage circuit 111a provides a reference voltage Vref1 that rises in response to the occurrence of leakage current Is1. In contrast, the reference voltage circuit 52a of this embodiment can supply a reference voltage Vref1 with desired temperature characteristics using a small number of circuit components and a small circuit area configuration.

[0130] <<Integrated Circuit 23c>> Next, with reference to Figure 8, an integrated circuit 23c of another embodiment will be described. Here, in Figure 8, components referenced by the same reference numerals as in Figure 1 correspond to the same components.

[0131] Integrated circuit 23c is an LVIC, similar to integrated circuit 23a. Similar to integrated circuit 23a, integrated circuit 23c controls the IGBT 31a by outputting a drive signal LO to the gate electrode of the IGBT 31a on the semiconductor chip 21a based on a signal LIN input from a microcontroller (not shown). Integrated circuit 23c includes a voltage generation circuit 41c, a temperature detection circuit 42a, a control circuit 43a, a memory circuit 44c, and a switch control circuit 45c. That is, integrated circuit 23c differs from integrated circuit 23a in that it includes a voltage generation circuit 41c, a memory circuit 44c, and a switch control circuit 45c.

[0132] Furthermore, an integrated circuit 23d (not shown) is provided on the high-side of integrated circuit 23c. Integrated circuit 23d has the same configuration as integrated circuit 23c and includes a voltage generation circuit 41d, a temperature detection circuit 42b, a control circuit 43b, a memory circuit 44d, and a switch control circuit 45d. In the relationship between integrated circuit 23c and integrated circuit 23d, the configuration of the low-side circuit and the high-side circuit are the same, so the following explanation will focus on the low-side circuit.

[0133] The memory circuit 44c stores data D(SW) corresponding to the on / off state information of switches 131a-131c, 122a-122c, 124a-124m, and 133a-133n, which will be described later in Figure 9. The memory circuit 44c is an EP-ROM (Erasable Programmable Read Only Memory) that can be written to or erased by a user via external communication.

[0134] The switch control circuit 45c outputs a signal Vsw to switch the state of each switch in the reference voltage circuit 52c. Based on the data D(SW), the switch control circuit 45c controls the on / off state of switches 131a-121c, 122a-122c, 124a-124m, and 133a-133n, which will be described later in Figure 9.

[0135] Here, the switch control circuit 45c corresponds to the "first control circuit".

[0136] ==Voltage Generation Circuit 41c== The voltage generation circuit 41c of this embodiment includes a temperature compensation circuit 51c and a reference voltage circuit 52c. The temperature compensation circuit 51c has the same configuration as the temperature compensation circuit 51a. On the other hand, the configuration of the reference voltage circuit 52c differs from that of the reference voltage circuit 52a.

[0137] The configuration of the reference voltage circuit 52c will be described in detail below with reference to Figure 9.

[0138] ==Reference voltage circuit 52c== Figure 9 shows an example of the configuration of the reference voltage circuit 52c. Here, in Figure 9, components referred to by the same symbols as those in the reference voltage circuit 52a in Figure 2 correspond to the same configuration.

[0139] The reference voltage circuit 52c includes MOS transistors 71, 72, variable resistors 121, 126, switches 122a~122c, 124a~124m, bipolar transistors 123a~123c, 125a~125m, and an output circuit 77.

[0140] Note that the variable resistor 121 includes switches 131a to 131c and resistors 132a to 132c, and the variable resistor 126 includes switches 133a to 133n and resistors 134a to 134n.

[0141] ===Overview of the operation of the 52c reference voltage circuit=== In the reference voltage circuit 52c, trimming is performed for both room temperature and high-temperature conditions, and the state of each switch can be adjusted so that a reference voltage Vref1 with desired characteristics is obtained at both room temperature and high-temperature conditions. Here, "room temperature" is, for example, 25°C, and "high temperature" is, for example, 175°C. Furthermore, the temperature set as "high temperature" is not limited to 175°C, but can be any temperature specified according to the specifications of the semiconductor module 10.

[0142] In particular, in the reference voltage circuit 52c, switches 124a to 124m are used to adjust the temperature characteristics of the reference voltage Vref1 when the temperature is changed. On the other hand, switches 122a to 122c, switches 131a to 131c, and switches 133a to 133n are used to correct the offset value of the reference voltage Vref1 for a desired voltage value.

[0143] In the trimming of the integrated circuit 23c of this embodiment, the number of connected resistors and bipolar transistors is changed by the switch control circuit 45c switching switches based on the data D(SW) stored in the memory circuit 44c. That is, switches 122a to 122c, switches 124a to 124m, switches 131a to 131c, and switches 133a to 133n each function as trimming elements for temperature characteristics and voltage adjustment.

[0144] However, the trimming performed in the reference voltage circuit 52c is not limited to trimming using the memory circuit 44c and a switch, but may also be performed by melting the wiring or resistor by laser trimming. Furthermore, when a switch is used as the trimming element, as in this embodiment, it is possible to perform trimming again to change the switch settings.

[0145] ===Configuration of the 52c reference voltage circuit=== The variable resistor 121 changes its resistance value based on the signal Vsw output by the switch control circuit 45c. Specifically, the variable resistor 121 includes switches 131a to 131c and resistors 132a to 132c, and the number of connected resistors 132a to 132c switches based on the signal Vsw output by the switch control circuit 45c. One end of the variable resistor 121 is connected to the MOS transistor 71.

[0146] In this embodiment, three switches 131a to 131c and three corresponding resistors 132a to 132c are provided. However, the number of switches 131a to 131c and corresponding resistors 132a to 132c provided does not need to be more than two, and is not limited to three.

[0147] Switches 122a to 122c switch the number of connections between bipolar transistors 123a to 123c based on the signal Vsw. Each of switches 122a to 122c is connected to the other end of the variable resistor 121.

[0148] Each of the bipolar transistors 123a to 123c makes a positive contribution to the temperature characteristics of the reference voltage Vref1. Each of the bipolar transistors 123a to 123c is connected to the corresponding switches 122a to 122c. That is, each of the bipolar transistors 123a to 123c is connected to the other end of the variable resistor 121 via the corresponding switches 122a to 122c.

[0149] Here, switches 122a to 122c are positioned on the variable resistor 121 side of the node where the base and collector electrodes of bipolar transistors 123a to 123c are diode-connected. This prevents current from flowing in from the base or collector electrode of the corresponding bipolar transistors 123a to 123c when switches 122a to 122c are in the off state.

[0150] Therefore, when switches 122a to 122c are in the off state, leakage current can be prevented from occurring in the corresponding bipolar transistors 123a to 123c.

[0151] In this embodiment, three switches 122a to 122c and three bipolar transistors 123a to 123c are provided, but the number of these is not limited to three; trimming is possible to any integer of two or more. In particular, the smaller the size of each bipolar transistor and the greater the number of switches and corresponding bipolar transistors, the more precisely the temperature characteristics of the output voltage Vref1 can be adjusted.

[0152] Switches 124a to 124m switch the number of connections between bipolar transistors 125a to 125m based on the signal Vsw. Switches 124a to 124m are connected to the drain electrodes of MOS transistor 72. In this embodiment, there are m switches 124a to 124m (where m is a positive integer).

[0153] Each of the bipolar transistors 125a to 125m makes a negative contribution to the temperature characteristics of the reference voltage Vref1. That is, the more bipolar transistors 125a to 125m are connected, the greater the leakage current when the temperature of the reference voltage circuit 52c increases. Consequently, the more bipolar transistors 125a to 125m are connected, the more negative the temperature characteristics of the reference voltage Vref1 become.

[0154] The bipolar transistors 125a to 125m are provided in a number corresponding to the switches 124a to 124m. In this embodiment, there are m bipolar transistors 125a to 125m (where m is a positive integer), similar to the switches 124a to 124m.

[0155] Bipolar transistors 125a to 125m are diode-connected transistors. Each of the bipolar transistors 125a to 125m is connected to the corresponding switch 124a to 124m.

[0156] Switches 124a to 124m are positioned on the variable resistor 121 side of the node where the base and collector electrodes of bipolar transistors 125a to 125m are diode-connected. This prevents leakage current from occurring in the corresponding bipolar transistors 125a to 125m when any of switches 124a to 124m are in the off state.

[0157] The variable resistor 126 varies its resistance value based on the signal Vsw. Specifically, the variable resistor 126 includes switches 133a to 133n and resistors 134a to 134n, and the number of connected resistors 134a to 134n is switched based on the signal Vsw output by the switch control circuit 45c. As a result, the variable resistor 126 reduces the offset value of the reference voltage Vref1 from a desired value (e.g., 1.2V).

[0158] Resistors 134a to 134n discretely change the resistance value of the variable resistor 126 according to the on / off state of switches 133a to 133n. This reduces the fluctuation of the resistance value of the variable resistor 126 in response to noise and current conditions compared to continuously varying the variable resistor 126.

[0159] In this embodiment, both resistors at the positions of variable resistor 121 and variable resistor 126 are variable resistors. However, one of these resistors may be a variable resistor and the other a resistor with a fixed resistance value.

[0160] Here, "switches 124a to 124m" correspond to "multiple first trimming elements." Also, "switches 131a to 131c" correspond to "multiple second trimming elements."

[0161] Furthermore, variable resistor 121 corresponds to the "first resistor," and variable resistor 126 corresponds to the "second resistor."

[0162] Furthermore, bipolar transistors 123a to 123c may each be bipolar transistors similar to bipolar transistor 74 in Figure 2, or they may be different bipolar transistors. Bipolar transistors 123a to 123c correspond to "multiple first bipolar transistors".

[0163] Similarly, bipolar transistors 125a to 125m may each be bipolar transistors similar to bipolar transistor 75 in Figure 2, or they may be different bipolar transistors. Bipolar transistors 125a to 125m correspond to "multiple second bipolar transistors".

[0164] ===Reference voltage Vref1 output from reference voltage circuit 52c==== Figure 10 shows an example of the reference voltage Vref1 output by the reference voltage circuit 52c.

[0165] Here, let r1 be the resistance of variable resistor 121, R1 be the combined resistance of bipolar transistors 123a to 123c, ΔIL be the leakage current of bipolar transistors 125a to 125m, R2 be their combined resistance, and r2 be the resistance of variable resistor 126.

[0166] Furthermore, let Ic1 be the current supplied by MOS transistor 71 to bipolar transistors 123a to 123c, and ΔIc1 be the increase in current Ic1 due to temperature rise. Similarly, let Ic2 be the current supplied by MOS transistor 72 to bipolar transistors 125a to 125m, and ΔIc2 be the increase in current Ic2 due to temperature rise. In this case, voltages V1 and V2 satisfy the following equations (A) and (B).

[0167] That is, with respect to voltage V1, V1=(Ic1+ΔIc1)×(r1+R1)...(A) And, regarding voltage V2, V2=(Ic2+ΔIc2-ΔIL)×(R2+r2)...(B) That is the case.

[0168] The output circuit 77 in Figure 9, which is a voltage divider circuit, divides the voltages V1 and V2. In this embodiment, the voltages V1 and V2 are divided by resistors 81 and 82 having equal resistance values, similar to Figure 2. That is, the output circuit 77 outputs a reference voltage Vref1 that satisfies the voltage Vref1 = (V1 + V2) / 2.

[0169] In the diagram, the positive slope of voltage V1 is greater than the negative slope of voltage V2, so the reference voltage circuit 52c outputs a reference voltage Vref1 that has a positive temperature characteristic.

[0170] Even if bipolar transistors 123a to 123c and bipolar transistors 125a to 125m are manufactured to approximately the same size, the temperature characteristics of voltages V1 and V2 may not completely cancel each other out. This is due to factors such as manufacturing variations, differences in connection points within the circuit layout, or the bias voltage for circuit operation not meeting ideal conditions.

[0171] Even in such cases, the reference voltage circuit 52c can obtain the desired temperature characteristics by adjusting the bit count of the bipolar transistor 125. Furthermore, these adjustments for the reference voltage circuit 52c will be explained with reference to Figures 11 and 12.

[0172] ===Adjustment of the temperature characteristics of the reference voltage Vref1=== Figure 11 shows an example of the reference voltage Vref1 when the number of switches 124a to 124m in the ON state is changed. In this embodiment, the figure shows the case when there are m switches 124a to 124m.

[0173] The figure shows the case where the number of ON switches 124a to 124m Ntr is gradually increased from 1 to m. When the number of ON switches 124a to 124m Ntr is increased, the number of bipolar transistors 125a to 125m connected in parallel also increases.

[0174] In this case, in equation (B), V2 = (Ic2 + ΔIc2 - ΔIL) × (R2 + r2), ΔIc2, ΔIL, and R2 increase. As a result, the negative slope of the voltage V2 increases as the temperature rises. Consequently, the slope of the voltage Vref = (V1 + V2) / 2 output from the reference voltage circuit 52c also changes in the negative direction.

[0175] On the other hand, if the number of switches 124a to 124m that are in the ON state (Ntr) is reduced, the negative slope of V2 becomes smaller, and the slope of the voltage Vref = (V1 + V2) / 2 output from the reference voltage circuit 52c changes in the positive direction.

[0176] In this embodiment, when Ntr=4, the difference between the value of the reference voltage Vref1 at room temperature (e.g., 25°C) and the value of the reference voltage Vref1 at high temperature (e.g., 175°C) is smallest.

[0177] Therefore, in the reference voltage circuit 52c of this embodiment, if you want to select a temperature characteristic of the reference voltage Vref1 that shows little temperature dependence between room temperature and high temperature, you can select Ntr=4.

[0178] In this embodiment shown in the figure, the reference voltage Vref1 output from the reference voltage circuit 52c is approximately 1.25V at room temperature, and slightly higher than 1.25V at high temperatures. Therefore, if we want to output a reference voltage Vref1 of, for example, 1.2V, at room temperature, the reference voltage Vref1 has an offset value of 1.25 - 1.2 = 0.05V.

[0179] The 0.05V offset value of the reference voltage Vref1 output from the reference voltage circuit 52c can also be adjusted as described below.

[0180] ===Adjusting the offset value of the reference voltage Vref1=== Figure 12 shows an example of the reference voltage Vref1 when the number of switches 133a to 133n in the ON state is changed.

[0181] The figure shows the case where the number of ON switches 124a to 124m, Nres, is gradually increased from 1 to m. In this embodiment, the figure shows the reference voltage Vref1 output from the reference voltage circuit 52c, assuming that Nres = 3 after completing the adjustment shown in Figure 11.

[0182] As the number Nres increases, r2 increases in the equation V2 = (Ic2 + ΔIc2 - ΔIL) × (R2 + r2) in equation (B). When Nres is increased, unlike when Ntr is increased, the factor Ic2 + ΔIc2 - ΔIL does not increase. Therefore, when Ntr is increased, the effect on the slope of V2 is smaller than when Nres is increased.

[0183] Therefore, when the number Nres is increased, the curve in the figure drawn by the reference voltage Vref1 output from the reference voltage circuit 52c shifts in the negative direction. On the other hand, when the number Nres is decreased, the curve in the figure drawn by the voltage Vref1 output from the reference voltage circuit 52c shifts in the positive direction.

[0184] In the reference voltage circuit 52c of this embodiment, if the desired reference voltage Vref1 at room temperature is 1.2V and it is desirable to select one with low temperature dependence at high temperatures, then Nres=6 is selected. In this case, the reference voltage circuit 52c outputs a reference voltage Vref1 that is close to 1.2V at room temperature and has low temperature dependence at high temperatures.

[0185] Furthermore, the resistance r1 can be varied by switching switches 131a to 131c of the variable resistor 121, and the combined resistance R1 of the bipolar transistors 123a to 123c can be varied by switching switches 122a to 122c. In this case, V1 = (Ic1 + ΔIc1) × (r1 + R1) in equation (A) will change, and the term that contributes to the positive temperature characteristic of the reference voltage Vref1 will change.

[0186] Therefore, the offset value of the reference voltage Vref1 may be adjusted by changing the voltage V1 by switching between switches 131a to 131c or switches 122a to 122c.

[0187] Here, the more switches 131a-131c or switches 122a-122c are in the ON state, the more the reference voltage Vref1 shifts to the positive side. On the other hand, the fewer switches 131a-131c or switches 122a-122c are in the ON state, the more the reference voltage Vref1 shifts to the negative side.

[0188] ===Trimming flow performed on the reference voltage circuit 52c=== Figure 13 shows an example of the trimming flow performed in the reference voltage circuit 52c. In the following, trimming is performed using a device such as a semiconductor tester (hereinafter referred to as "tester"), which is not shown in the figure.

[0189] First, at room temperature (e.g., 25°C), the desta trims the number of connections for bipolar transistors 125a to 125m and acquires data adjusted so that the reference voltage Vref1 reaches a desired value (e.g., 1.2V) (S1).

[0190] In this context, when we say that the tester performs trimming on the number of connections of a predetermined element (e.g., a resistor), we mean that the tester rewrites the data in the IC's memory via a terminal (not shown) so that the number of connections of the predetermined element changes.

[0191] Next, at high temperatures (e.g., 175°C), the tester trims the number of connections for bipolar transistors 125a to 125m and obtains data for the reference voltage Vref1 (S2).

[0192] Furthermore, the tester trims the number of connected bipolar transistors 125a to 125m so that the difference between the reference voltage Vref1 at room temperature and the output voltage Vref1 at high temperature is minimized (S3). This allows the reference voltage circuit 52 to set the temperature characteristics of the output reference voltage Vref1 to the desired temperature characteristics.

[0193] Then, at room temperature, the tester trims the connections of resistors 132a-132c, 134a-134n, or bipolar transistors 123a-123c (S4). This allows the reference voltage circuit 52c to adjust the offset of the reference voltage Vref1 at room temperature from a desired value (e.g., 1.2V).

[0194] As described above, the reference voltage circuit 52c allows adjustment of the temperature characteristics of the output reference voltage Vref1 and the offset from the desired value.

[0195] ===Summary=== The semiconductor module 10 and voltage generation circuit 41a of this embodiment, as well as the voltage generation circuit 101a of a comparative example, have been described above. The semiconductor module 10 includes an integrated circuit 23a that includes a reference voltage circuit 52a.

[0196] The integrated circuit 23a includes a reference voltage circuit 52a. The reference voltage circuit 52a includes a current source made up of a MOS transistor 71, a current source made up of a MOS transistor 72 connected in parallel with the MOS transistor 71, a resistor 73 with one end connected to the drain electrode of the MOS transistor 71, a bipolar transistor 74 connected to the other end of the resistor 73 and having its base electrode and collector electrode connected, a bipolar transistor 75 connected to the MOS transistor 72 and having its base electrode and collector electrode connected, a resistor 76 connected to the emitter electrode of the bipolar transistor 75, and an output circuit 77 that outputs a voltage based on the voltage V1 output from the drain electrode of the MOS transistor 71 and the voltage V2 output from the drain electrode of the MOS transistor 72.

[0197] As a result, the reference voltage circuit 52a can supply a reference voltage Vref1 with desired temperature characteristics based on voltages V1 and V2, using a small number of circuit components and a small circuit area configuration.

[0198] Furthermore, the bipolar transistors 74 and 75 in this embodiment are of the same size. This allows the effects of leakage currents Ic1 and Ic2 on the rise in voltage V1 and the fall in voltage V2 that occur in a temperature range above a predetermined temperature threshold Tth to be adjusted to be approximately identical in bipolar transistors 74 and 75.

[0199] Furthermore, the resistance values ​​of resistors 73 and 76 in this embodiment are equal. This allows the coefficients in the influence of leakage currents Is1 and Is2 on voltages V1 and V2 to be adjusted to be equal.

[0200] The integrated circuit 23c includes a reference voltage circuit 52c having the configuration shown in Figure 9. The reference voltage circuit 52c includes a current source composed of a MOS transistor 71, a current source composed of a MOS transistor 72 connected in parallel with the MOS transistor 71, a variable resistor 121, bipolar transistors 123a to 123c, a plurality of switches 124a to 124m, a plurality of bipolar transistors 125a to 125m, a variable resistor 126, and an output circuit 77 that outputs a reference voltage Vref1 based on the voltage V1 output from the current source composed of the MOS transistor 71 and the voltage V2 output from the current source composed of the MOS transistor 72.

[0201] Even when adjusting the size of bipolar transistors 123a~123c and 125a~125m, it can be difficult to adjust the temperature characteristics of the reference voltage Vref1. This is due to factors such as manufacturing variations, differences in connection points within the circuit layout, or the bias voltage for circuit operation not meeting ideal conditions. In such cases, however, the integrated circuit 23c allows for adjustment of voltages V1 and V2 to obtain a reference voltage Vref1 with the desired temperature characteristics.

[0202] Furthermore, the integrated circuit 23c includes a plurality of switches 122a to 122c connected to the other end of the variable resistor 121, and each of the plurality of bipolar transistors 123a to 123c is connected to the other end of the resistor via the plurality of switches 122a to 122c.

[0203] This allows the integrated circuit 23c to adjust the temperature characteristics of the reference voltage Vref1 by changing the size of the bipolar transistors 123a to 123c.

[0204] Furthermore, at least one of the elements provided at the connection points of the multiple switches 122a to 122c or the elements provided at the connection points of the multiple switches 124a to 124m is a plurality of switches, and the integrated circuit 23c includes a switch control circuit 45c that controls the on / off state of the plurality of switches.

[0205] As a result, in the integrated circuit 23c, when trimming is performed on the size of bipolar transistors 123a to 123c or bipolar transistors 125a to 125m, the size can be readjusted by trimming again.

[0206] Furthermore, at least one of the elements provided at the connection point of the variable resistor 121 or the element provided at the connection point of the variable resistor 126 is a variable resistor, and the switch control circuit 45c controls the resistance value of the variable resistor.

[0207] This makes it possible to trim the resistance value of the variable resistor 121 or the variable resistor 126 in the integrated circuit 23c, and by changing these resistance values, the offset of the reference voltage Vref1 at room temperature from a desired value can be adjusted.

[0208] Furthermore, the variable resistor 121 or variable resistor 126 includes a plurality of switches 131a to 131c or switches 133a to 133n for changing the resistance value of the variable resistor 121 or variable resistor 126, and the switch control circuit 45c controls the on / off state of the plurality of switches of the variable resistor 121 or variable resistor 126.

[0209] This allows the resistance value of the variable resistor 121 or variable resistor 126 to be adjusted discretely in the integrated circuit 23c. Therefore, the resistance value of the variable resistor 121 or variable resistor 126 will fluctuate less in response to noise and current conditions compared to when the variable resistor 121 or variable resistor 126 is continuously varied.

[0210] Furthermore, the system includes a memory circuit 44c that stores data D(SW) containing information indicating the state of multiple switches 122a~122c, 124a~124m, 131a~131c, and 133a~133n, and the switch control circuit 45c controls the on / off state of the multiple switches based on the data D(SW).

[0211] This allows the trimming performed by the switch in the integrated circuit 23c to be repeated, changing the switch settings.

[0212] Furthermore, the output circuit 77 of this embodiment includes a resistor 81, one end of which is connected to the drain electrode of the MOS transistor 71, and a resistor 82, one end of which is connected to the output of the MOS transistor 72 and the other end of which is connected to the other end of the resistor 81. In addition, the reference voltage Vre1 is the voltage generated at the node between the resistors 81 and 82.

[0213] Thus, the output circuit 77 in this embodiment is a voltage divider circuit composed of resistors 81 and 82. In this way, the output circuit 77 does not include any elements that would further increase the circuit area, such as operational amplifiers.

[0214] Therefore, the reference voltage circuit 52a of this embodiment can supply a reference voltage Vref1 with desired temperature characteristics based on voltages V1 and V2, using a small number of circuit components and a small circuit area configuration.

[0215] Furthermore, the resistance values ​​of resistors 81 and 82 in this embodiment are equal. As a result, the output circuit 77 divides the voltages V1 and V2 equally. Therefore, when the rise in voltage V1 and the fall in voltage V2 are approximately the same, the reference voltage circuit 52a can output a nearly flat reference voltage Vref1.

[0216] Furthermore, the temperature compensation circuit 51a of this embodiment includes a bipolar transistor 67 through which a current Iref flows. In this embodiment, the MOS transistors 71 and 72 become current sources through which the current supplied from the drain electrode corresponds to the current Iref.

[0217] As a result, currents Ic1 and Ic2 increase due to the generation of leakage current in the bipolar transistor 67. In other words, when leakage currents Is1 and Is2 increase in the reference voltage circuit 52a, currents Ic1 and Ic2 will also increase.

[0218] Therefore, within the temperature range of the temperature threshold Tth, the leakage currents Is1 and Is2 satisfy the equation Is1 = Is2 and increase at equal rates. As a result, the contribution of the leakage currents Is1 and Is2 to the voltages V1 and V2 becomes easier to control, the reference voltage Vref1 from the reference voltage circuit 52a becomes stable, and this is particularly useful when a nearly flat reference voltage Vref1 is output even with temperature changes.

[0219] Furthermore, in this embodiment, the current source that supplies current to the node to which voltage V1 is applied is MOS transistor 71, and the current source that supplies current to the node to which voltage V2 is applied is MOS transistor 72. The source electrodes of MOS transistors 71 and 72 are connected to the power line L1a, and a predetermined gate voltage is applied to the gate electrodes of MOS transistors 71 and 72.

[0220] Thus, in the reference voltage circuit 52a, the current sources that supply current to the nodes to which voltages V1 and V2 are applied are MOS transistors 71 and 72, and do not include bipolar elements. Therefore, in the reference voltage circuit 52a, no large leakage current, such as the leakage current that occurs in bipolar elements, is generated from the current sources that supply current to the nodes to which voltages V1 and V2 are applied.

[0221] Furthermore, in this embodiment, the sizes of MOS transistors 71 and 72 are equal. As a result, equal currents are supplied from MOS transistors 71 and 72 to the nodes to which voltages V1 and V2 are applied.

[0222] Furthermore, the temperature compensation circuit 51a of the integrated circuit 23a in this embodiment includes a bipolar transistor 67 and a MOS transistor 62, which is a bias voltage source that supplies a bias voltage corresponding to the current value of the current flowing through the bipolar transistor 67. The MOS transistor 62 supplies a bias voltage to the gate electrodes of the respective MOS transistors 71 and 72.

[0223] As a result, when leakage currents Is1 and Is2 occur in bipolar transistors 74 and 75, leakage current also occurs in bipolar transistor 67. Depending on the current value of bipolar transistor 67, the voltage supplied from MOS transistor 62 to the gate electrodes of MOS transistors 71 and 72 decreases. Consequently, the currents Ic1 and Ic2 supplied from MOS transistors 71 and 72 increase.

[0224] In other words, as leakage currents Is1 and Is2 increase, currents Ic1 and Ic2 also increase. Therefore, within the temperature range of the temperature threshold Tth, leakage currents Is1 and Is2 satisfy the equation Is1 = Is2 and increase at an equal rate. As a result, the contribution of leakage currents Is1 and Is2 to voltages V1 and V2 becomes easier to control, the reference voltage Vref1 becomes stable, and this is particularly useful when outputting a reference voltage Vref1 that is nearly flat even with temperature changes.

[0225] Furthermore, in this embodiment, the integrated circuit 23a includes a current mirror circuit 68 including P-type MOS transistors 61 and 62, a current mirror circuit 69 including N-type MOS transistors 63 and 64 to which current is supplied from the current mirror circuit 68, a bipolar transistor 65 connected to one end of the current mirror circuit 69 with its base electrode and collector electrode connected, a resistor 66 connected to the other end of the current mirror circuit 69, and a bipolar transistor 67 connected to the resistor 66 with its base electrode and collector electrode connected. In addition, the gate electrodes of the MOS transistors 71 and 72 are connected to the node connecting the current mirror circuits 68 and 69.

[0226] As a result, when the gate voltages of the MOS transistors 71 and 72 of the reference voltage circuit 52a decrease due to the leakage currents Is1 and Is2 of the bipolar transistors 74 and 75, the temperature compensation circuit 51a supplies the reduced voltage. This stabilizes the operation of the integrated circuit 23a as a whole.

[0227] Furthermore, the semiconductor module 10 of this embodiment comprises an integrated circuit 23a and a switching element which is an IGBT 31a. The integrated circuit 23a includes a control circuit 43a that controls the driving of the switching element connected to the gate electrode of the IGBT 31a based on an input signal LIN, and the control circuit 43a controls the driving of the switching element based on the input signal LIN and a reference voltage Vref1.

[0228] This allows the control circuit 43a to control the driving of the switching element based on a reference voltage Vref1 having a desired temperature characteristic supplied by the reference voltage circuit 52a.

[0229] Although the present invention has been described above using embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments. Various modifications or improvements can be made to the above embodiments. It is obvious to those skilled in the art that this is possible. It is also evident from the claims that the technical scope of the present invention may include, without departing from the spirit thereof, forms with such modifications or improvements and their equivalents.

[0230] It should be noted that the execution order of operations, procedures, steps, and stages in the apparatus, systems, programs, and methods shown in the claims, specifications, and drawings is not explicitly stated as "before," "prior to," etc., and that these can be implemented in any order unless the output of a previous process is used in a later process. Even if the operation flow in the claims, specifications, and drawings is described using phrases such as "first," "next," etc. for convenience, it does not mean that it is essential to perform the operations in that order. [Explanation of Symbols]

[0231] 10 Semiconductor Modules 11 Load 12,22 Power supply 21 Semiconductor chips 23 Integrated Circuits 31 IGBT 32 diodes 41,101 Voltage generation circuit 42 Temperature detection circuit 43 Control circuits 44 Memory circuit 45 Switch control circuit 51 Temperature compensation circuit 52,111 Reference voltage circuit 61-64 MOS transistors 65, 67, 74, 75 Bipolar Transistors 66, 73, 76, 81, 82 resistors 68,69 Current mirror circuit 71,72 MOS transistors 77 Output Circuit 91 circuit board 92 N-well region 93 N+ Collector Area 94 P+ base region 95 N+ emitter region 96 Collector terminal 97 Base terminal 98 Emitter terminal 121,126 Variable resistors 122a~122c, 124a~124m switch 123a~123c, 125a~125m Bipolar Transistors 131a~131c, 133a~133n switches 132a~132c, 134a~134n resistors

Claims

1. First current source and A second current source is provided in parallel with the first current source, A first resistor, one end of which is connected to the output of the first current source, A first bipolar transistor, which is connected to the other end of the first resistor and is diode-connected, A second bipolar transistor, which is connected to the output of the second current source and is diode-connected, A second resistor, one end of which is connected to the second bipolar transistor and the other end of which is grounded, An output circuit that outputs a third voltage, which is a reference voltage, based on a first voltage output from the first current source and a second voltage output from the second current source. Equipped with, The output circuit described above is The first voltage and the second voltage are added together to output the third voltage. Integrated circuit.

2. The integrated circuit according to claim 1, The sizes of the first bipolar transistor and the second bipolar transistor are equal. Integrated circuit.

3. An integrated circuit according to claim 1 or 2, The resistance value of the first resistor and the resistance value of the second resistor are equal. Integrated circuit.

4. First current source and A second current source is provided in parallel with the first current source, A first resistor, one end of which is connected to the output of the first current source, A first bipolar transistor, which is connected to the other end of the first resistor and is diode-connected, A plurality of first trimming elements connected to the output of the second current source, Each of the aforementioned multiple first trimming elements is connected to a plurality of second bipolar transistors that are diode-connected, A second resistor, one end of which is connected to the plurality of second bipolar transistors and the other end of which is grounded, An output circuit that outputs a third voltage, which is a reference voltage, based on a first voltage output from the first current source and a second voltage output from the second current source. Equipped with, The output circuit described above is The first voltage and the second voltage are added together to output the third voltage. Integrated circuit.

5. The integrated circuit according to claim 4, The device comprises a plurality of second trimming elements connected to the other end of the first resistor, Each of the plurality of first bipolar transistors is connected to the other end of the first resistor via the plurality of second trimming elements. Integrated circuit.

6. The integrated circuit according to claim 5, At least one of the plurality of first trimming elements or the plurality of second trimming elements is a plurality of switches, The aforementioned integrated circuit is The system includes a first control circuit that controls the on / off state of the plurality of switches. Integrated circuit.

7. The integrated circuit according to claim 6, At least one of the first resistor or the second resistor is a variable resistor, The first control circuit controls the resistance value of the variable resistor. Integrated circuit.

8. The integrated circuit according to claim 7, The variable resistor includes a plurality of switches for changing the resistance value of the variable resistor. The first control circuit controls the on / off state of the plurality of switches of the variable resistor. Integrated circuit.

9. An integrated circuit according to any one of claims 6 to 8, The system includes a memory circuit that stores information indicating the state of the multiple switches, The first control circuit controls the on / off state of the plurality of switches based on the information. Integrated circuit.

10. An integrated circuit according to any one of claims 1 to 9, The output circuit includes a third resistor, one end of which is connected to the output of the first current source, A fourth resistor is included, with one end connected to the output of the second current source and the other end connected to the other end of the third resistor. The third voltage is the voltage that occurs at the node between the third resistor and the fourth resistor. Integrated circuit.

11. The integrated circuit according to claim 10, The resistance values ​​of the third resistor and the fourth resistor are equal. Integrated circuit.

12. An integrated circuit according to any one of claims 1 to 11, It includes a third bipolar transistor that generates a reference current, The first current source and the second current source generate a current corresponding to the reference current. Integrated circuit.

13. An integrated circuit according to any one of claims 1 to 12, The first current source includes a first MOS transistor, The second current source includes a second MOS transistor. The source electrodes of the first MOS transistor and the second MOS transistor are connected to a power line. A predetermined voltage is applied to the gate electrodes of the first MOS transistor and the second MOS transistor, Integrated circuit.

14. The integrated circuit according to claim 13, The sizes of the first MOS transistor and the second MOS transistor are equal. Integrated circuit.

15. An integrated circuit according to claim 13 or 14, The third bipolar transistor, The system includes a bias voltage source that generates a bias voltage corresponding to the current value of the current flowing through the third bipolar transistor, The bias voltage source supplies the generated bias voltage to the respective gate electrodes of the first MOS transistor and the second MOS transistor. Integrated circuit.

16. An integrated circuit according to claim 13 or 14, A first current mirror circuit including a P-type MOS transistor, A second current mirror circuit including an N-type MOS transistor to which current is supplied from the first current mirror circuit, A fifth resistor connected to one end of the second current mirror circuit, A third bipolar transistor, which is connected to the aforementioned fifth resistor and also diode-connected, A fourth bipolar transistor, which is diode-connected and connected to the other end of the second current mirror circuit, Includes, The gate electrodes of the first MOS transistor and the second MOS transistor are connected to the node connecting the first current mirror circuit and the second current mirror circuit. Integrated circuit.

17. An integrated circuit according to any one of claims 1 to 16, Equipped with a switching element, The integrated circuit includes a second control circuit connected to the control electrode of the switching element, which controls the driving of the switching element based on an input signal. The second control circuit controls the driving of the switching element based on the input signal and the third voltage. Semiconductor module.

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