Semiconductor device, switching power supply device, composite power supply device, and linear IC
The semiconductor device addresses the need for simplified configuration and reduced external connections by using a common terminal and function selection unit to manage external capacitors, enabling versatile function selection and improved performance in power supply devices.
Patent Information
- Application Number
- JP2024120260
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2024-07-25
- Publication Date
- 2026-02-05
AI Technical Summary
There is an increasing demand for reducing the number of terminals connected to external elements and simplifying the configuration in semiconductor devices with multi-function selection capabilities, particularly in semiconductor devices that utilize a capacitor for determining functions based on impedance.
A semiconductor device with a common terminal connected to an external capacitor, a function selection unit that performs a selection operation based on the charge stored in the capacitor, and an internal power supply unit that supplies voltage to internal circuits, allowing the external capacitor to be connected to the function selection unit during selection operations and to the internal power supply unit during voltage supply operations, thereby reducing the number of external connections and simplifying the configuration.
This configuration allows for versatile function selection without altering the internal IC structure, reduces the number of external terminals, and simplifies the device configuration while enhancing functionality in applications such as switching power supplies and composite power supplies.
Smart Images
Figure 2026018914000001_ABST
Abstract
Description
[Technical Field]
[0001] The present invention relates to a semiconductor device, a switching power supply device, a composite power supply device, and a linear IC. [Background technology]
[0002] The semiconductor device has a determination circuit that makes a determination based on the impedance of an externally connected element. When a voltage is supplied from an internal power supply unit, the semiconductor device is provided with a capacitor in addition to the element used in the determination circuit (see, for example, Patent Document 1). [Prior art documents] [Patent documents]
[0003] [Patent Document 1] Re-tabled publication 2018 / 030230
[0004] [overview] In semiconductor devices having such multi-function selection capabilities, there is an increasing demand for reducing the number of terminals connected to external elements and simplifying the configuration.
[0005] According to one aspect of the present disclosure, a semiconductor device includes a common terminal configured to be connected to an external capacitor, a function selection unit configured to perform a selection operation to output a selection signal for selecting a function determined according to the amount of charge stored in the external capacitor, and an internal power supply unit configured to supply a voltage to an internal circuit provided inside the semiconductor device, wherein the external capacitor and the function selection unit are electrically connected when the selection operation is performed, and the external capacitor and the voltage supply unit and the internal circuit are electrically connected when a supply operation is performed to supply a supply voltage from the internal power supply unit to the internal circuit. [Brief explanation of the drawings]
[0006] [Figure 1] FIG. 1 is a schematic circuit diagram of a semiconductor device. [Figure 2]FIG. 2 is a timing chart showing the states of the signals when the semiconductor device is in operation. [Figure 3] FIG. 3 is a schematic circuit diagram of the semiconductor device according to the second embodiment. [Figure 4] FIG. 4 is a schematic circuit diagram showing the configuration of an example of a switching power supply device using a semiconductor device. [Figure 5] FIG. 5 is a schematic circuit diagram showing the configuration of an example of a composite power supply device using a semiconductor device.
[0007] [Detailed explanation] Hereinafter, examples of embodiments of the present disclosure will be described in detail with reference to the drawings. In each of the drawings, the same parts are designated by the same reference numerals, and duplicate descriptions of the same parts will be omitted as a general rule. In this specification, for the sake of simplicity, symbols or signs referring to information, signals, physical quantities, functional units, circuits, elements, or components may be used, and the names of the information, signals, physical quantities, functional units, circuits, elements, or components corresponding to the symbols or signs may be omitted or abbreviated.
[0008] Furthermore, when referring to any circuit element, wiring, or a plurality of parts forming a circuit, "connection" includes a mechanical connection as well as an electrical connection, in other words, a state in which electricity flows. In other words, "connect" includes "electrically connecting."
[0009] A switch can be in an on state or an off state. When a switch is in the on state, conduction occurs between both ends of the switch. On the other hand, when a switch is in the off state, conduction does not occur between both ends of the switch. In the following description, the on state and the off state may be simply expressed as on and off, respectively.
[0010] An example of a switching element may be a MOS (Metal Oxide Semiconductor) field effect transistor. A MOS field effect transistor is a transistor whose gate structure consists of at least three layers: a layer made of a conductor or a semiconductor such as polysilicon with a low resistance, an insulating layer, and a P-channel, N-channel, or intrinsic semiconductor layer. In other words, the gate structure of a MOS field effect transistor is not limited to a three-layer structure of metal, oxide, and semiconductor.
[0011] First Embodiment A first embodiment of the present disclosure will be described. FIG. 1 is a schematic circuit diagram of a semiconductor device 100. FIG. 2 is a timing chart showing the states of various signals during operation of the semiconductor device 100. The semiconductor device 100 is used, for example, as a control device for controlling a power supply device mounted on a vehicle or the like. The semiconductor device 100 is capable of executing a function selected from a plurality of functions. The semiconductor device 100 has an internal power supply unit 1, an internal circuit 2, a function selection unit 3, and a control unit 4.
[0012] 1, the semiconductor device 100 has a common terminal 101, a common wiring 102, an internal circuit connecting wiring 103, a first switch 51, a second switch 52, and a third switch 53. In the semiconductor device 100, the common terminal 101 is connected to the common wiring 102. As shown in FIG. 1, an external capacitor C1 is provided outside the semiconductor device 100, and the external capacitor C1 is connected to the common terminal 101. A first end of the external capacitor C1 is connected to the common terminal 101, and a second end of the external capacitor C1 is connected to ground. The external capacitor C1 is a so-called output capacitor, and is provided to stabilize the supply voltage VREG.
[0013] In the semiconductor device 100, the internal power supply unit 1, the internal circuit 2, the function selection unit 3, and the control unit 4 may be integrated into one package as a functional IC (Integrated Circuit). The common terminal 101, the common wiring 102, the internal circuit connection wiring 103, the first switch 51, the second switch 52, and the third switch 53 are arranged inside the package of the functional IC.
[0014] <Internal circuit 2> The internal circuit 2 is a circuit included in the semiconductor device 100, such as a driver circuit that drives a power supply device, a timer circuit, a clock circuit, etc. As shown in FIG. 1 , the internal circuit 2 is supplied with a supply voltage VREG from an internal power supply unit 1. The function selection unit 3 and the control unit 4 are driven by an input voltage VIN supplied from outside the semiconductor device 100. The internal circuit 2 is connected to an internal circuit connecting wiring 103. The internal circuit connecting wiring 103 is connected to a common wiring 102 via a third switch 53.
[0015] <Internal power supply section 1> The internal power supply unit 1 is configured to use, for example, an operational amplifier 11, with a voltage supplied to a non-inverting input terminal of the operational amplifier 11 and an output terminal and an inverting input terminal shorted together. The output terminal of the operational amplifier 11 is connected to a second switch 52. The internal power supply unit 1 supplies a stable supply voltage VREG to the internal circuit 2. The internal power supply unit 1 is connected to a common wiring 102 via the second switch 52.
[0016] <Function selection section 3> The function selecting unit 3 has a current source 31, a reference voltage output unit 32, and a comparing unit 33. The function selecting unit 3 is connected to a common wiring 102 via a first switch 51. To explain in more detail, the current source 31 and comparing unit 33 of the function selecting unit 3 are connected to the common wiring 102 via the first switch 51. When the first switch 51 is in an on state, a current from the current source 31 is supplied to the external capacitor C1 via the common wiring 102 and common terminal 101.
[0017] <Reference voltage output unit 32> The reference voltage output unit 32 has a reference voltage source 34 and a voltage dividing unit 35. The reference voltage source 34 outputs a reference voltage VREF to the voltage dividing unit 35. The voltage dividing unit 35 has a first voltage dividing resistor 351, a second voltage dividing resistor 352, a third voltage dividing resistor 353, a fourth voltage dividing resistor 354, and a fifth voltage dividing resistor 355, which are connected in series in this order. In the voltage dividing unit 35, a first terminal of the first voltage dividing resistor 351 is connected to the reference voltage source 34, and a second terminal of the fifth voltage dividing resistor 355 is connected to ground.
[0018] In the voltage dividing section 35, a first end of the first voltage dividing resistor 351 and a wiring connected to the reference voltage source 34 are connected at a first connection point P1. The first voltage dividing resistor 351 and the second voltage dividing resistor 352 are connected at a second connection point P2, the second voltage dividing resistor 352 and the third voltage dividing resistor 353 are connected at a third connection point P3, the third voltage dividing resistor 353 and the fourth voltage dividing resistor 354 are connected at a fourth connection point P4, and the fourth voltage dividing resistor 354 and the fifth voltage dividing resistor 355 are connected at a fifth connection point P5.
[0019] In the voltage dividing unit 35, the reference voltage VREF is divided by the first voltage dividing resistor 351 to the fifth voltage dividing resistor 355, and first reference voltage Vr1 to fifth reference voltage Vr5, each of which has a different voltage, are generated. In the voltage dividing unit 35, the voltage at the first connection point P1 is the first reference voltage Vr1. Similarly, the voltage at the second connection point P2 is the second reference voltage Vr2, the voltage at the third connection point P3 is the third reference voltage Vr3, the voltage at the fourth connection point P4 is the fourth reference voltage Vr4, and the voltage at the fifth connection point P5 is the fifth reference voltage Vr5. The first reference voltage Vr1 to fifth reference voltage Vr5 generated in the voltage dividing unit 35 are in the order of first reference voltage Vr1 > second reference voltage Vr2 > third reference voltage Vr3 > fourth reference voltage Vr4 > fifth reference voltage Vr5.
[0020] The first connection point P1 to the fifth connection point P5 of the voltage dividing unit 35 are connected to the first comparator 331 to the fifth comparator 335 (described later), respectively, of the comparing unit 33. As a result, the first reference voltage Vr1 to the fifth reference voltage Vr5 are supplied to the non-inverting input terminals of the first comparator 331 to the fifth comparator 335, respectively.
[0021] <Current source 31> 1, the current source 31 is connected to the common wiring 102 via the first switch 51. The current source 31 is supplied with an input power supply VIN, is driven by the input voltage VIN, and has a configuration in which it outputs a current of a determined current value.
[0022] <Comparison section 33> The comparator 33 receives the first reference voltage Vr1 to the fifth reference voltage Vr5 generated by the voltage divider 35 of the reference voltage output unit 32 and a selection voltage VSL corresponding to the charge amount of the external capacitor C1. The comparator 33 compares the selection voltage VSL with the first reference voltage Vr1 to the fifth reference voltage Vr5 and outputs the comparison results as the first selection signal Sct1 to the fifth selection signal Sct5. The first selection signal Sct1 to the fifth selection signal Sct5 are output to the controller 4.
[0023] The comparison unit 33 has a first comparator 331, a second comparator 332, a third comparator 333, a fourth comparator 334, and a fifth comparator 335. The first comparator 331 to the fifth comparator 335 are all comparators having the same configuration. A selection voltage VSL is input to the non-inverting input terminals of the first comparator 331 to the fifth comparator 335. A first reference voltage Vr1 to a fifth reference voltage Vr5 are input to the inverting input terminals of the first comparator 331 to the fifth comparator 335, respectively.
[0024] The outputs of the first to fifth comparators 331 to 335 are high when the selection voltage VSL is greater than the first to fifth reference voltages Vr1 to Vr5, respectively, and low when it is less than the first to fifth reference voltages Vr1 to Vr5. For example, the output of the third comparator 331 is high when the selection voltage VSL is greater than the third reference voltage Vr3, and low when it is less than the third reference voltage Vr3. Furthermore, when the output of the third reference voltage Vr3 is high, the outputs of the fourth comparator 334 and the fifth comparator 335, which receive the fourth reference voltage Vr4 and the fifth reference voltage Vr5, respectively, which are smaller than the third reference voltage Vr3, also become high. In this embodiment, the first to fifth selection signals Sct1 to Sct5 are output to the control unit 4.
[0025] <Control unit 4> The control unit 4 detects the first selection signal Sct1 to the fifth selection signal Sct5. Then, the control unit 4 selects a predetermined function from among the plurality of functions in response to the first selection signal Sct1 to the fifth selection signal Sct5, and outputs a control signal Scr to the internal circuit 2 that is determined to drive the selected function. The plurality of functions may include those related to the operation of a configuration in which the semiconductor device 100 is used (for example, a switching power supply device or a composite power supply device, which will be described later). The plurality of functions may also be a configuration in which a function that outputs a signal to be output externally is selected. The plurality of functions may be functions that can be implemented by a circuit internal to the semiconductor device 100.
[0026] The control unit 4 is also configured to output a first switch drive signal S_sw1, a second switch drive signal S_sw2, and a third switch drive signal S_sw3 to drive the first switch 51, the second switch 52, and the third switch 53.
[0027] The first switch drive signal S_sw1, the second switch drive signal S_sw2, and the third switch drive signal S_sw3 are all signals that assume a high level or a low level. When the first switch drive signal S_sw1, the second switch drive signal S_sw2, and the third switch drive signal S_sw3 are at a high level, the first switch 51, the second switch 52, and the third switch 53 are in an on state, and when they are at a low level, they are in an off state.
[0028] <Discharge section 6> The semiconductor device 100 has a discharge unit 6 that discharges the external capacitor C1. A discharge instruction signal Sdc is input to the discharge unit 6 from the control unit 4. The discharge instruction signal Sdc is a signal that takes a high level or a low level, and when a high-level discharge instruction signal Sdc is input, the discharge unit 6 is a circuit configured to discharge the external capacitor C1.
[0029] The semiconductor device 100 has the configuration described above. As shown in Fig. 2, the semiconductor device 100 has a configuration that can execute a discharging operation M1, a selecting operation M2, and a supplying operation M3. In the semiconductor device 100, the discharging operation M1, the selecting operation M2, and the supplying operation M3 are controlled by a control unit 4. The operations of the control unit 4 in the discharging operation M1, the selecting operation M2, and the supplying operation M3 will be described below.
[0030] <Discharge operation M1> As shown in FIG. 2, during the discharging operation M1, the control unit 4 outputs a high-level discharge instruction signal Sdc. This causes the discharging unit 6 to discharge the charge stored in the external capacitor C1. In other words, the discharging operation M1 is an operation that drives the discharging unit 6 to discharge the external capacitor C1. By performing the discharging operation M1, the semiconductor device 100 sets the charge stored in the external capacitor C1 to "0." Note that, as shown in FIG. 2, during the discharging operation M1, the first switch driving signal S_sw1, the second switch driving signal S_sw2, and the third switch driving signal S_sw3 are at a low level.
[0031] <Supply operation M3> As shown in FIG. 2, during supply operation M3, the control unit 4 outputs a high-level second switch drive signal S_sw2 and a high-level third switch drive signal S_sw3. This causes the second switch 52 and the third switch 53 to be turned on. Also, as shown in FIG. 2, during supply operation M3, the first switch drive signal S_sw1 and the discharge instruction signal Sdc are low-level. This causes the first switch to be turned off, and the external capacitor C1 to be chargeable. Therefore, the internal power supply unit 1 is connected to the external capacitor C1 via the common wiring 102 and to the internal circuit 2 via the internal circuit connection wiring 103. As a result, the supply voltage VREG from the internal power supply unit 1 charges the external capacitor C1 and is supplied to the internal circuit 2.
[0032] <Selection action M2> As shown in Fig. 2, during selection operation M2, the control unit 4 outputs a high-level first switch drive signal S_sw1. This turns the first switch 51 on. Also, as shown in Fig. 2, during selection operation M2, the second switch drive signal S_sw2, the third switch drive signal S_sw3, and the discharge instruction signal Sdc are low. This turns the second switch 52 and the third switch 53 off, and the external capacitor C1 is connected to the current source 31 of the function selection unit 3.
[0033] In the selection operation M2, the external capacitor C1 is charged with a current from the current source 31, and a selection voltage VSL corresponding to the amount of charge accumulated by charging the external capacitor C1 is input to the comparison unit 33 of the function selection unit 3. In the selection operation M2, the comparison unit 33 inputs the selection voltage VSL corresponding to the amount of charge accumulated in the external capacitor C1. The first comparator 331 to the fifth comparator 335 compare the selection voltage VSL with the first reference voltage Vr1 to the fifth reference voltage Vr5, respectively. Then, the first selection signal Sct1 to the fifth selection signal Sct5 corresponding to the comparison results are output.
[0034] As shown in FIG. 2, at the start of the selection operation M2, the amount of charge stored in the external capacitor C1 is "0." At this time, the selection voltage VSL is also "0." At the start of the selection operation M2, the selection voltage VSL is smaller than any of the first reference voltage Vr1 to the fifth reference voltage Vr5. Therefore, at the start of the selection operation M2, the first selection signal Sct1 to the fifth selection signal Sct5 are all at a low level.
[0035] In the selection operation M2, the external capacitor C1 is charged with a current from the current source 31, and the selection voltage VSL increases as the external capacitor C1 is charged. When the selection voltage VSL becomes greater than the fifth reference voltage Vr5, the fifth selection signal Sct5 switches from low to high. Similarly, when the selection voltage VSL becomes greater than the fourth reference voltage Vr4, the fourth selection signal Sct4 also switches from low to high. In this way, when the selection voltage VSL becomes greater than each reference voltage, the selection signal output from the comparator switches from low to high.
[0036] 2, the selection operation M2 ends after time T1 has elapsed. In this state, the selection voltage VSL is greater than the third reference voltage Vr3 and less than the second reference voltage Vr2. Therefore, when the selection operation M2 ends, the function selection unit 3 outputs the first selection signal Sct1 and the second selection signal Sct2 at a low level and the third selection signal Sct3, the fourth selection signal Sct4, and the fifth selection signal Sct5 at a high level.
[0037] When the selection operation M2 is completed, the control unit 4 outputs a control signal Scr corresponding to a combination of high or low levels of the first selection signal Sct1 to the fifth selection signal Sct5 at the time of completion of the selection operation M2 to the internal circuit 2. The internal circuit 2 is operated in any function selected from a plurality of functions.
[0038] The semiconductor device 100 is configured to supply a current to an external capacitor C1 and output a signal corresponding to the magnitude of a selection voltage VSL corresponding to the amount of charge on the external capacitor C1. The amount of charge on the capacitor is proportional to the current and the time the current is supplied. Furthermore, the voltage relative to the amount of charge on the capacitor is inversely proportional to the capacitance of the capacitor.
[0039] Therefore, the semiconductor device 100 can be configured such that the current value output from the current source 31 and the duration of the selection operation M2 are constant, and the output levels of the first select signal Sct1 to the fifth select signal Sct5 are adjusted according to the capacitance of the external capacitor C1. With this configuration, by changing the external capacitor C1, the first select signal Sct1 to the fifth select signal Sct5 can be changed, that is, the selected function can be changed, without changing the internal configuration of the IC. This improves the versatility of the semiconductor device 100.
[0040] Furthermore, the semiconductor device 100 can reduce the number of external connection terminals compared to conventional semiconductor devices that have an external capacitor to which the internal power supply unit 1 and the internal circuit 2 are connected, and an external resistor to which the function selection unit 3 is connected, thereby simplifying the configuration of the semiconductor device 100.
[0041] In this embodiment, the capacitance of the external capacitor C1 is adjusted to set a predetermined combination of levels of the first selection signal Sct1 to the fifth selection signal Sct5, but this is not limiting. For example, the length of the time T1 of the selection operation M2 may be changed, or the value of the current output from the current source 31 may be changed.
[0042] When the selection operation M2 is completed, the control unit 4 switches the first switch drive signal S_sw1 from high to low. At this time, the selection voltage VSL from the external capacitor C1 is no longer input to the function selection unit 3. As a result, the first selection signal Sct1 to the fifth selection signal Sct5 from the comparison unit 33 all switch to low.
[0043] Therefore, in the semiconductor device 100, the control unit 4 may be configured to store information about the levels of the first selection signal Sct1 to the fifth selection signal Sct5 received in the selection operation M2. The comparison unit 33 may also be configured to hold and continue outputting the levels of the first selection signal Sct1 to the fifth selection signal Sct5 determined in the selection operation M2. In this configuration, the comparison unit 33 has a function of resetting the first selection signal Sct1 to the fifth selection signal Sct5 to a low level in response to a signal from the control unit 4. The control unit 4 may then control the comparison unit 3 to continue outputting the held first selection signal Sct1 to the fifth selection signal Sct5 during the supply operation M3, or may control the comparison unit 3 to reset the first selection signal Sct1 to the fifth selection signal Sct5 after a certain period of time has elapsed since the start of the supply operation M3.
[0044] Second Embodiment A second embodiment of the present disclosure will be described. Fig. 3 is a schematic circuit diagram of a semiconductor device 100A of the second embodiment. The semiconductor device 100A shown in Fig. 3 differs from the semiconductor device 100 in a function selection unit 3A and a control unit 4A. Components of the semiconductor device 100A that are substantially the same as those of the semiconductor device 100 are given the same reference numerals, and detailed descriptions of the same parts will be omitted.
[0045] 3, the reference voltage output unit 32A of the semiconductor device 100A has one output terminal and is capable of outputting any one of the first reference voltage Vr1 to the fifth reference voltage Vr5 as the reference output voltage VR. The reference voltage output unit 32A has a standard voltage source 34, a voltage divider 35, and a selector 36. The first reference voltage Vr1 to the fifth reference voltage Vr5 and an adjustment signal SLC are input to the selector 36. The selector 36 is configured to output any one of the first reference voltage Vr1 to the fifth reference voltage Vr5 as the reference voltage VR in accordance with the adjustment signal SLC. The adjustment signal SLC is output from the control unit 4A.
[0046] The reference voltage source 34 may be configured to have a variable voltage value of the output voltage and to output different reference voltages in response to the adjustment signal SLC. This configuration makes it possible to omit the voltage divider and the selector.
[0047] The comparison unit 33A has one comparator 331A. The selection voltage VSL is input to a non-inverting input terminal of the comparator 331A. The reference voltage VR from the selector 36 is input to an inverting input terminal of the comparator 331A. The comparator 331A outputs the comparison result between the reference voltage VR and the selection voltage VSL as a selection signal SctA.
[0048] For example, assume that the selection voltage VSL is greater than the fourth reference voltage Vr4 and less than the third reference voltage Vr3. In this case, the control unit 4A outputs an adjustment signal SLC that sets the reference voltage VR to the fourth reference voltage Vr4, and the control unit 4A acquires a high-level selection signal SctA.
[0049] Furthermore, the control unit 4A outputs an adjustment signal SLC that sets the reference voltage VR to the third reference voltage Vr3, thereby obtaining a low-level selection signal SctA. Thus, the adjustment signal SLC when the selection signal SctA becomes high varies depending on the selection voltage VSL. The control unit 4A can select any function from multiple functions based on the adjustment signal SLC that can obtain a high-level selection signal SctA.
[0050] As described above, the selection signal VSL increases over time. Therefore, when the control unit 4A receives a high-level selection signal SctA, the control unit 4A may output an adjustment signal SLC that switches the reference voltage to the next reference voltage VR.
[0051] In the semiconductor device 100A configured as described above, the number of comparators constituting the comparator can be reduced, which allows the semiconductor device 100A to be made smaller and consume less power.
[0052] <Use> 4 is a schematic circuit diagram showing the configuration of an example of a switching power supply device 200 using the semiconductor device 100. The switching power supply device 200 is used as a voltage source that supplies a power supply voltage in vehicles such as automobiles, conveyance devices, industrial robots, and the like.
[0053] As shown in FIG. 4, the switching power supply device 200 includes the semiconductor device 100, an external capacitor C1, a switching output stage 300, an inductor L1, and a smoothing capacitor C2.
[0054] In the switching power supply device 200, the switching output stage 300 has a high-side switching element 301 and a low-side switching element 302 arranged between the input voltage VIN and the ground voltage. The high-side switching element 301 and the low-side switching element 302 are both N-channel MOS transistors. However, this configuration is not limiting, and the high-side switching element may be a P-channel MOS transistor and the low-side switching element may be an N-channel MOS transistor.
[0055] The source of the high-side switching element 301 is connected to the drain of the low-side switching element 302. The drain of the high-side switching element 301 is connected to the input voltage VIN, and the source of the low-side switching element 302 is connected to the ground voltage. A high-side gate signal HG and a low-side gate signal LG from the control unit 4 are input to the gates of the high-side switching element 301 and the low-side switching element 302, respectively.
[0056] The high-side switching element 301 and the low-side switching element 302 are complementarily turned on or off by a high-side gate signal HG and a low-side gate signal LG. Note that "complementary" refers to a state in which one is turned on while the other is turned off. Here, this includes the case in which they are both turned off at the same time, but does not include the case in which they are both turned on at the same time.
[0057] The switching power supply device 200 outputs an output voltage VOUT by operating a high-side switching element 301 and a low-side switching element 302 in a complementary manner. The output voltage VOUT is determined by the on-duty of the high-side switching element 301.
[0058] The internal circuit 2 of the semiconductor device 100 used in the switching power supply device 200 includes a driver circuit for driving the switching output stage 300 and a duty determination circuit for determining the on-duty of the high-side switching element 301. In the semiconductor device 100, the multiple functions set in the internal circuit 2 can include multiple on-duties.
[0059] That is, the control unit 4 transmits a control signal Scr to the internal circuit 2 so as to drive the internal circuit 2 at a determined on-duty in accordance with the first selection signal Sct1 to the fifth selection signal Sct5 from the function selection unit 3. That is, in the semiconductor device 100, the switching output stage 300 is operated at an on-duty in accordance with the first selection signal Sct1 to the fifth selection signal Sct5. This allows the switching power supply device 200 to output an output voltage VOUT that is, for example, a voltage required in a vehicle, by changing the capacitance of the external capacitor C1 connected to the semiconductor device 100. That is, the versatility of the switching power supply device 200 can be improved.
[0060] 4 is a step-down converter, but a step-up converter is also applicable. Furthermore, the function of the switching power supply device 200 is the on-duty of the high-side switching element 301, but is not limited to this.
[0061] It is also possible to use a linear IC in which an LDO (Low Drop-Out) regulator circuit is arranged instead of the switching output stage 300. In such a configuration, the output voltage VOUT of the LDO regulator circuit can be made adjustable and adjusted from the internal circuit 2. Even in such a configuration, the desired output voltage VOUT can be output by selecting an external capacitor C1 with an appropriate capacitance.
[0062] 5 is a schematic circuit diagram showing an example of the configuration of a composite power supply 400 using the semiconductor device 100. As shown in FIG. 5, the composite power supply 400 has the semiconductor device 100 and three output stages 401, 402, and 403.
[0063] In the composite power supply 400, the first output stage 401, the second output stage 402, and the third output stage 403 are switching regulators that use DC / DC converters. In the composite power supply 400, the output current IOUT can be adjusted by changing the number of output stages that are in operation (referred to as being active).
[0064] In the composite power supply 400, the internal circuit 2 can set a number of functions, such as increasing the number of output stages to be activated and the on-duty value of the high-side switching element. That is, the control unit 4 outputs a control signal Scr according to the first selection signal Sct1 to the fifth selection signal Sct5 to the internal circuit 2. The internal circuit 2 determines the output stage to be activated according to the number of output stages to be activated in response to the control signal Scr, and outputs a high-side gate signal HG and a low-side gate signal LG to the output stage to be activated, which operate the high-side switching element at the determined on-duty value.
[0065] In this way, the output current IOUT of the composite power supply 400 can be adjusted by the capacitance of the external capacitor C1 of the semiconductor device 100. This makes it possible to enhance the versatility of the composite power supply 400.
[0066] Furthermore, in the composite power supply device 400, the output stages 401, 402, and 403 are switching regulators, but are not limited to this, and at least one of them may be a linear regulator.
[0067] <Other> The above-described embodiments should be considered to be illustrative in all respects and not restrictive. The technical scope of the present invention is indicated by the claims, not by the description of the above-described embodiments, and should be understood to include all modifications that fall within the meaning and scope of the claims.
[0068] <Additional Notes> The semiconductor device (100, 100A) described above has the following features: a common terminal (101) to which an external capacitor (C1) is connected externally; a function selection unit (3, 3A) configured to perform a selection operation (M2) that outputs selection signals (Sct1 to Sct5) for selecting a predetermined function according to the amount of charge stored in an external capacitor (C1); an internal power supply unit (1) configured to supply voltage to an internal circuit (2) provided therein; The configuration may be a first configuration in which the external capacitor (C1) is connected to the function selection unit (2) when the selection operation (M2) is performed, and the external capacitor (C1) is electrically connected to the internal power supply unit (1) and the internal circuit (2) when the supply operation (M3) is performed to supply a supply voltage (VREG) from the internal power supply unit (1) to the internal circuit (2).
[0069] In the semiconductor device (100, 100A) of the first configuration, In the selection operation (M2), the function selection unit (3, 3A) may be configured (second configuration) to charge the external capacitor (C1) for a predetermined time (T1).
[0070] In the semiconductor device (100, 100A) of the first or second configuration, A configuration (third configuration) in which the supply operation (M3) is performed after the selection operation (M2) is performed may also be used.
[0071] In the semiconductor device (100, 100A) having any one of the first to third configurations, A configuration (fourth configuration) in which a discharge operation (M1) for discharging the external capacitor (C1) is performed before the selection operation (M1) is performed may also be used.
[0072] In the semiconductor device (100, 100A) having any one of the first to fourth configurations, The function selection unit (3, 3A) may be configured (fifth configuration) to hold and continue to output the selection signals (Sct1 to Sct5) after the selection operation (M2) is completed.
[0073] In the semiconductor device (100, 100A) having any one of the first to fifth configurations, The function selection unit (3, 3A) includes a reference voltage output unit (32, 32A) capable of outputting different reference voltages (Vr1 to Vr5); The sixth configuration may include a comparator (33, 33A) configured to compare a selection voltage (VSL) corresponding to the charge stored in the external capacitor (C1) with each reference voltage (Vr1 to Vr5) and output the result of the comparison.
[0074] In the semiconductor device (100) of the sixth configuration, The reference voltage output unit (32) a reference voltage source (34) configured to output a predetermined reference voltage (VREF); a voltage dividing unit (35) configured to divide the reference voltage (34) and supply a plurality of reference voltages (Vr1 to Vr5) of different voltages; The comparison section (33) may have a configuration (seventh configuration) including a plurality of comparators (331 to 335) configured to compare the selection voltage (VSL) with each of the reference voltages (Vr1 to Vr5) and output the results.
[0075] In the semiconductor device (100A) of the sixth configuration, The reference voltage output section (32A) may be configured to supply different reference voltages (Vr1 to Vr5) to the comparing section (32) (eighth configuration).
[0076] In the semiconductor device (100, 100A) having any one of the first to eighth configurations, a common wiring (102) configured to be connected to the common terminal (101); an internal circuit connection wiring (103) configured to be connected to the internal circuit (2); a first switch (51) arranged between a common wiring (102) and a function selection unit (3, 3A); a second switch (52) arranged between the common wiring (102) and the internal power supply unit (1); a third switch (53) arranged between the common wiring (102) and the internal circuit connecting wiring (103); A control unit (4), The control unit (4) may be configured (ninth configuration) such that when the selection operation (M2) is performed, the first switch (51) is in a conductive state and the second switch (52) and the third switch (53) are in a non-conductive state, and when the supply operation (M3) is performed, the first switch (51) is in a non-conductive state and the second switch (52) and the third switch (53) are in a conductive state.
[0077] The switching power supply device (400) described above has the following features: Any one of the first to ninth semiconductor devices (100, 100A), and a switching output stage (300) configured to be driven by the semiconductor device (100, 100A).
[0078] The composite power supply device (200) described above has the following features: Any one of the first to ninth semiconductor devices (100, 100A), a plurality of output stages (401, 402, 403) configured to be drivable by the semiconductor device (100, 100A); At least one of the plurality of output stages (401, 402, 403) may be operated by the semiconductor device (100, 100A) (eleventh configuration).
[0079] The linear IC explained above is It may also be a configuration (twelfth configuration) using any one of the first to ninth semiconductor devices (100, 100A). [Explanation of symbols]
[0080] 100, 100A Semiconductor Device 101 Common terminal 102 Common wiring 103 Internal circuit connection wiring 200 Switching Power Supply 300 switching output stage 301 High-side switching element 302 Low-side switching element 400 Combined Power Supply 401 1st output stage 402 Second output stage 403 3rd output stage 1 Internal power supply section 11 Operational Amplifiers 2 Internal circuit 3, 3A Function selection section 31 Current source 32, 32A Reference voltage output section 33, 33A comparison section 331A Comparator 331 First comparator 332 Second Comparator 333 Third Comparator 334 Fourth Comparator 335 5th comparator 34 Reference voltage source 35 Voltage divider 351 1st voltage dividing resistor 352 Second voltage dividing resistor 353 Third voltage dividing resistor 354 4th voltage dividing resistor 355 5th voltage dividing resistor 36 Selector 4, 4A control section 51 First Switch 52 Second Switch 53 Third Switch 6 Discharge section C1 external capacitor C2 smoothing capacitor L1 inductor P1 First connection point P2 Second connection point P3 Third connection point P4 4th connection point P5 5th connection point VREF Reference voltage VREG supply voltage VSL Select voltage Vr1 First reference voltage Vr2 Second reference voltage Vr3 Third reference voltage Vr4 Fourth reference voltage Vr5 Fifth reference voltage VIN input voltage VOUT Output voltage IOUT Output current HG High-side gate signal LG Low side gate signal M1 discharge operation M2 selection operation M3 supply operation S_sw1 First switch drive signal S_sw2 Second switch drive signal S_sw3 Third switch drive signal Sct1 First selection signal Sct2 Second selection signal Sct3 Third selection signal Sct4 4th selection signal Sct5 5th selection signal SctA selection signal SDC discharge instruction signal Scr control signal SLC adjustment signal T1 time
Claims
1. a common terminal configured to be connected to an external capacitor; a function selection unit configured to perform a selection operation to output a selection signal for selecting a function determined in accordance with the amount of charge stored in the external capacitor; an internal power supply unit configured to supply voltage to an internal circuit provided therein; A semiconductor device configured such that the external capacitor and the function selection unit are electrically connected when the selection operation is performed, and the external capacitor is electrically connected to the internal power supply unit and the internal circuit when a supply operation is performed to supply a supply voltage from the internal power supply unit to the internal circuit.
2. 2. The semiconductor device according to claim 1, wherein in the selection operation, the function selection section is configured to charge the external capacitor for a predetermined time.
3. 2. The semiconductor device according to claim 1, wherein the supply operation is performed after the selection operation is performed.
4. 2. The semiconductor device according to claim 1, wherein a discharge operation is performed to discharge the external capacitor before the selection operation is performed.
5. 2. The semiconductor device according to claim 1, wherein the function selection section is configured to hold and continue to output the selection signal after the selection operation is completed.
6. the function selection unit includes a reference voltage output unit capable of outputting different reference voltages; 2. The semiconductor device according to claim 1, further comprising: a comparator configured to compare a selection voltage corresponding to the charge stored in said external capacitor with each of said reference voltages and output the result of the comparison.
7. The reference voltage output unit a reference voltage source configured to output a predetermined reference voltage; a voltage dividing unit configured to divide the standard voltage and supply a plurality of reference voltages having different voltages; 7. The semiconductor device according to claim 6, wherein the comparison section has a configuration including a plurality of comparators configured to compare the selection voltage with each of the reference voltages and output the results of the comparison.
8. 7. The semiconductor device according to claim 6, wherein the reference voltage output section supplies the reference voltages, which are different voltages, to the comparison section.
9. a common wiring configured to be connected to the common terminal; an internal circuit connection wiring configured to be connected to the internal circuit; a first switch arranged between the common wiring and the function selection unit; a second switch arranged between the common line and the internal power supply unit; a third switch arranged between the common wiring and the internal circuit connecting wiring; a control unit; 2. The semiconductor device according to claim 1, wherein the control unit is configured to control the first switch to a conductive state and the second switch and the third switch to a non-conductive state when the selection operation is performed, and to control the first switch to a non-conductive state and the second switch and the third switch to a conductive state when the supply operation is performed.
10. A semiconductor device according to any one of claims 1 to 9; a switching output stage driven by the semiconductor device.
11. A semiconductor device according to any one of claims 1 to 9; a plurality of output stages configured to be driven by the semiconductor device; A composite power supply device configured such that at least one of a plurality of output stages is operated by the semiconductor device.
12. A linear IC configured using the semiconductor device according to any one of claims 1 to 9.