Temperature detection protection circuit and high-voltage integrated chip

Abstract

The invention discloses a temperature detection protection circuit and a high-voltage integrated chip, the temperature detection protection circuit comprises a mirror image constant current unit, a hysteresis comparison unit and a temperature detection unit, the temperature detection unit comprises at least two diodes, and the mirror image constant current unit provides a reference voltage signal for the hysteresis comparison unit; the reference current is provided for the temperature detection unit, the temperature detection unit feeds back a temperature detection voltage signal to the hysteresis comparison unit based on the reference current and the temperature change, and the hysteresis comparison unit outputs a temperature protection signal for controlling the chip to work by comparing the reference voltage signal with the temperature detection voltage signal; the mirror image constant current unit is used for providing constant current and the temperature characteristic of a diode, the temperature detection unit collects the temperature in the chip through the diode and converts the temperature into a temperature detection voltage signal, the temperature detection voltage signal is compared with a protection threshold value and outputs a temperature protection signal, the temperature in the chip is detected in real time, and the high-voltage integrated chip and an application system thereof are protected. And the reliability of the high-voltage integrated chip is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of integrated circuits, and in particular to a temperature detection protection circuit and a high-voltage integrated chip. Background Art

[0002] With the development of industrial level and science and technology, the speed of power electronic products is getting faster and faster, and people's requirements for performance are getting higher and higher. Among them, the off-chip temperature detection module is an important part of today's monolithic integrated intelligent power driver chip. Its accuracy directly determines the efficiency and reliability of its application system in the actual application environment to a large extent. High precision, low power consumption and easy integration have become important design goals of the temperature detection module. The high voltage level and pulse generation circuit on the high-voltage integrated chip HVIC are the main sources of heat. Once an abnormal situation occurs, its internal temperature rises sharply. If the off-chip temperature detection module detects inaccurately at this time, that is, the output value of the temperature detection module is greatly different from the actual value, the microcontroller receiving the temperature signal at the front end of the system will cause a series of misoperations, reducing the system's working efficiency, or failing to make a corresponding protection response in time, so that the heat accumulates further, damages the reliability, and finally causes the chip to fail. Therefore, it is of great significance to design a high-precision temperature detection circuit for high-voltage integrated chips. Summary of the invention

[0003] In view of the above-mentioned deficiencies in the prior art, the purpose of the present invention is to provide a temperature detection protection circuit and a high-voltage integrated chip. The temperature detection protection circuit provides a constant current based on a mirror constant current unit of a low temperature drift coefficient. By utilizing the temperature characteristics of a diode, the temperature detection unit collects the temperature inside the chip through a diode and converts it into a temperature detection voltage signal, which is compared with the temperature protection threshold and outputs a temperature protection signal for controlling the operation of the chip. The high-voltage integrated chip is integrated with the aforementioned temperature detection protection circuit, which can detect the temperature inside the chip in real time, protect the high-voltage integrated chip and its application system from damage due to high temperature, and thereby improve the reliability of the high-voltage integrated chip.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions:

[0005] A temperature detection protection circuit comprises a mirror image constant current unit, a hysteresis comparison unit, and a temperature detection unit, wherein the temperature detection unit comprises at least two diodes, the mirror image constant current unit provides a reference voltage signal to the hysteresis comparison unit, and provides a reference current to the temperature detection unit, the temperature detection unit feeds back a temperature detection voltage signal to the hysteresis comparison unit based on the reference current and temperature change, and the hysteresis comparison unit outputs a temperature protection signal for controlling the operation of a chip by comparing the reference voltage signal with the temperature detection voltage signal.

[0006] In the temperature detection protection circuit, the temperature detection unit includes a diode D1 and a diode D2, the diode D1 and the diode D2 are connected in series in the forward direction, the reference current provided by the mirror constant current unit is input into the positive electrode of the diode D1, the positive electrode of the diode D1 is connected to the hysteresis comparison unit and feeds back the temperature detection voltage signal, and is grounded to the negative electrode of the diode D2.

[0007] In the temperature detection protection circuit, the mirror constant current unit includes a MOS tube M1, a MOS tube M2, a MOS tube M3, a MOS tube M16, and a resistor R1. The sources of the MOS tube M1, the MOS tube M2, and the MOS tube M16 are all connected to the power supply voltage. The gate of the MOS tube M1 is respectively connected to its own drain, the gate of the MOS tube M2, and the gate of the MOS tube M16. The drain of the MOS tube M1 is respectively connected to the gate and the drain of the MOS tube M3. The source of the MOS tube M3 is grounded. The drain of the MOS tube M2 is connected to one end of the resistor R1 and provides a reference voltage signal to the hysteresis comparison unit. The other end of the resistor R1 is grounded. The drain of the MOS tube M16 inputs a reference current to the temperature detection unit.

[0008] In the temperature detection protection circuit, the hysteresis comparison unit includes MOS tube M4, MOS tube M5, MOS tube M6, MOS tube M7, MOS tube M8, MOS tube M9, MOS tube M10, MOS tube M11, MOS tube M12, MOS tube M13, MOS tube M14, and MOS tube M15. The source of the MOS tube M5, the MOS tube M7, the MOS tube M8, the MOS tube M9, the MOS tube M10, and the drain of the MOS tube M4 are all connected to the power supply voltage, the gate of the MOS tube M5 is respectively connected to the drain and gate of the MOS tube M7, the gate of the MOS tube M8, the drain of the MOS tube M9, and the drain of the MOS tube M11, and the drain of the MOS tube M5 is respectively connected to the drain and gate of the MOS tube M6 and the gate of the MOS tube M13. The gate of the MOS tube M15 is respectively connected to the drain and gate of the MOS tube M10, the drain of the MOS tube M8, the gate of the MOS tube M9, and the drain of the MOS tube M12. The drain of the MOS tube M15 is connected to the drain of the MOS tube M13. The drain of the MOS tube M15 is the output end of the temperature protection signal. The drain of the MOS tube M14 is respectively connected to the source of the MOS tube M11 and the source of the MOS tube M12. The gate of the MOS tube M14 is connected to the gate of the MOS tube M4. The gate of the MOS tube M11 is connected to the mirror constant current unit and receives a reference voltage signal. The gate of the MOS tube M12 is connected to the temperature detection unit and receives a temperature detection voltage signal. The sources of the MOS tube M4, the MOS tube M6, the MOS tube M8, and the MOS tube M14 are all grounded.

[0009] In the temperature detection protection circuit, the MOS tube M1, MOS tube M2, MOS tube M5, MOS tube M7, MOS tube M8, MOS tube M9, MOS tube M10, MOS tube M15, and MOS tube M16 are all N-channel depletion-type field effect tubes, and the MOS tube M3, MOS tube M4, MOS tube M6, MOS tube M11, MOS tube M12, MOS tube M13, and MOS tube M14 are all P-channel depletion-type field effect tubes.

[0010] The present application also provides a high-voltage integrated chip, including the temperature detection protection circuit, filter shaping circuit, dead zone interlock circuit, fault logic control circuit, high-side drive circuit, and bootstrap circuit as described above, wherein the filter shaping circuit is connected to the high-side drive circuit via the dead zone interlock circuit, the temperature detection protection circuit is connected to the high-side drive circuit via the fault logic control circuit, and the bootstrap circuit is connected to the high-side drive circuit.

[0011] The high-voltage integrated chip further comprises a low-side driving circuit, and the low-side driving circuit is respectively connected to the dead zone interlocking circuit and the fault logic control circuit.

[0012] The high-voltage integrated chip also includes an overload protection circuit, which is connected to the fault logic control circuit.

[0013] The high-voltage integrated chip also includes an undervoltage protection circuit, which is connected to the fault logic control circuit.

[0014] The high-voltage integrated chip further comprises a fault output circuit, and the fault output circuit is connected to the fault logic control circuit.

[0015] Beneficial effects:

[0016] The present invention provides a temperature detection protection circuit and a high-voltage integrated chip. The temperature detection protection circuit provides a constant current based on a mirror constant current unit of a low temperature drift coefficient. The temperature detection unit collects the temperature in the chip through the diode and converts it into a temperature detection voltage signal by utilizing the temperature characteristics of the diode. The temperature is compared with the temperature protection threshold and outputs a temperature protection signal for controlling the operation of the chip. The high-voltage integrated chip is integrated with the above-mentioned temperature detection protection circuit, which can detect the temperature in the chip in real time, protect the high-voltage integrated chip and its application system from being damaged by high temperature, and thus improve the reliability of the high-voltage integrated chip. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A circuit diagram of a temperature detection protection circuit provided by the present invention;

[0018] Figure 2 A topological structure diagram of the high-voltage integrated chip provided by the present invention;

[0019] Explanation of main component symbols: 1-temperature detection protection circuit, 1.1-mirror constant current unit, 1.2-hysteresis comparison unit, 1.3-temperature detection unit, 2-filter shaping circuit, high-side drive circuit, 3-dead zone interlock circuit, 4-fault logic control circuit, 5-high-side drive circuit, 6-bootstrap circuit, 7-low-side drive circuit, 8-overload protection circuit, 9-undervoltage protection circuit, 10-fault output circuit. DETAILED DESCRIPTION

[0020] The present invention provides a temperature detection protection circuit and a high-voltage integrated chip. In order to make the purpose, technical solution and effect of the present invention clearer and more specific, the present invention is further described in detail with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0021] In the description of the present invention, it should be understood that the terms "first", "second" and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features.

[0022] See also Figure 1 A temperature detection protection circuit includes a mirror constant current unit 1.1, a hysteresis comparison unit 1.2, and a temperature detection unit 1.3, wherein the temperature detection unit 1.3 includes at least two diodes, and the mirror constant current unit 1.1 provides a reference voltage signal V to the hysteresis comparison unit 1.2. REF , and provide a reference current I to the temperature detection unit 1.3 REF2 The temperature detection unit 1.3 is based on the reference current I REF2 And the temperature change feeds back the temperature detection voltage signal V to the hysteresis comparison unit 1.2 T The hysteresis comparison unit 1.2 compares the reference voltage signal V REF And the temperature detection voltage signal V T Output temperature protection signal used to control chip operation.

[0023] The temperature detection protection circuit in the present invention provides a constant current based on the mirror constant current unit 1.1 of the low temperature drift coefficient. By utilizing the temperature characteristics of the diode, the temperature detection unit 1.3 collects the temperature inside the chip through the diode and converts it into a temperature detection voltage signal, which is compared with the temperature protection threshold, and then outputs a temperature protection signal for controlling the operation of the chip, thereby achieving the purpose of protecting the chip.

[0024] The specific application principle lies in the temperature characteristics of the diode. The diode is essentially composed of a PN junction formed by a P-type semiconductor and an N-type semiconductor. A space charge layer is formed at the junction interface on both sides, and a self-built electric field is formed at the same time. If the external voltage is 0, that is, zero bias, the majority carriers diffuse due to the concentration difference in the PN junction, and the minority carriers drift due to the existence of the self-built electric field. Their effects are just the opposite. As the diffusion movement proceeds, the electric field in the space charge region gradually increases, which increases the drift movement, and finally makes the diffusion current and drift current of the PN junction equal to each other to reach a dynamic equilibrium state, so the net current in the PN junction is 0.

[0025] However, when a forward or reverse voltage is applied to the diode, the dynamic equilibrium state of the diode at zero bias will be broken, showing the unique volt-ampere (voltage-current) characteristics of the diode (PN junction). The diode has three working regions, namely the forward bias region, the reverse cutoff region and the reverse breakdown region.

[0026] When a reverse bias voltage is applied to the diode, if the reverse voltage value does not exceed the threshold voltage, the current flowing through the diode is the reverse current formed by the drift motion of minority carriers. At this time, the reverse current is very small, and the diode is in a reverse cut-off state. Its current presents a reverse approximately constant characteristic, that is, a reverse saturation current; if the reverse voltage is greater than the threshold voltage, the slightly changing reverse bias voltage will cause the reverse current to increase suddenly and rapidly. At this time, the diode operates in the reverse breakdown region, but the exponentially increasing current can easily cause electrical and thermal breakdown of the PN junction, causing the diode to lose its unidirectional conductivity or even burn out the diode.

[0027] When a forward bias voltage is applied to the diode, the drift current caused by the self-built electric field decreases sharply relative to the diffusion current of the majority carriers, causing the depletion layer width to continue to decrease, and the net current of the diode begins to flow from the P region to the N region. According to the Maxwell-Boltzmann approximation equation, the minority carrier concentration nP of the depletion layer in the P region at this time is:

[0028] n p =n p0 exp(qV D / KT)1.1

[0029] In the above formula (1.1), V D is the forward bias voltage applied to the diode, T is the thermodynamic temperature, K is the Boltzmann constant, which is 1.380×10-23J / K, q is the charge of the electron, which is 1.602×10-19C, and nP0 is the electron equilibrium concentration, which is expressed as follows:

[0030] n P0 =n i 2 / Na 1.2

[0031] In the above formula (1.2), n i is the intrinsic carrier concentration, and Na is the acceptor concentration. Similarly, the minority electron concentration p in the depletion layer of the N region is N for:

[0032] P N =P N0 exp(qV D / KT)1.3

[0033] In the above formula (1.3), P N0 is the hole equilibrium concentration, which is expressed as:

[0034] P N0 =n i 2 / Nd 1.4

[0035] In the above formula (1.4), Nd is the donor concentration. Since the minority carriers far away from the depletion layer are equal to their equilibrium concentration, the electron concentration in the P region decreases as the distance from the depletion layer increases, and the same is true for the hole concentration in the N region; it is precisely because there is a gradient difference in the electron and hole concentrations that causes diffusion currents, and the sum of these diffusion currents constitutes the total current ID flowing through the diode:

[0036] I D =qAD N (n P –n P0 ) / L N +qAD P (p N –p N0 ) / L P 1.5

[0037] In the above formula (1.5), D N and L N are the diffusion coefficient and diffusion length of minority carrier-electrons in the P region, D P and L P are the diffusion coefficient and diffusion length of the minority carrier-hole in the N region, respectively, and A is the PN junction area. From the above equations (1.1), (1.3) and (1.5), we can get that the current I of the ideal diode is D With forward bias voltage V D Relationship:

[0038] I D =I S (exp(qV D / KT)-1)1.6

[0039] In the above formula (3.6), I S is the reverse saturation current of the diode, which can be expressed as:

[0040] I S =qAD N n P0 / L N +qAD P n N0 / L P 1.7

[0041] From the above formula (1.7), we can see that the forward current of the diode increases exponentially with the forward bias voltage, so when the forward bias voltage V D ≥kT / q, the constant term -1 in equation (1.7) can be ignored. Therefore, when a constant current I passes through a forward diode, the voltage drop V across the diode is:

[0042] V=kT ln(I / I S) / q 1.8

[0043] If two bias currents I1 and I2 = pI1 are added to the two diodes respectively, then the difference in voltage drop between the two diodes ΔV D for:

[0044] ΔV D =V2-V1=kT ln(pI1 / I S ) / q-kT ln(I1 / I S ) / q=kT ln(p) / q 1.9

[0045] It can be seen from the above formula (1.9) that the voltage drop difference ΔVD between the two diodes is proportional to the absolute temperature and is the PTAT voltage, so the diode can be used to detect the internal temperature of the chip.

[0046] Specifically, see Figure 1 In the temperature detection protection circuit of the present invention, the temperature detection unit 1.3 includes a diode D1 and a diode D2, the diode D1 and the diode D2 are connected in series in a forward direction, the reference current provided by the mirror constant current unit 1.1 is input to the positive electrode of the diode D1, and the positive electrode of the diode D1 is connected to the hysteresis comparison unit 1.3 and feeds back the temperature detection voltage signal V T , and the cathode of the diode D2 is grounded. Based on the above formula (1.9), it can be seen that the voltage drop difference ΔVD between the two diodes is proportional to the absolute temperature. Therefore, when the reference current I REF2 In the case of unchanged, as the temperature collected by the diode increases, the temperature detection voltage signal V T The voltage value of the temperature detection voltage signal V T The voltage value drops.

[0047] Specifically, see Figure 1 In the temperature detection protection circuit, the mirror constant current unit 1.1 includes a MOS tube M1, a MOS tube M2, a MOS tube M3, a MOS tube M16, and a resistor R1. The sources of the MOS tube M1, the MOS tube M2, and the MOS tube M16 are all connected to the power supply voltage. The gate of the MOS tube M1 is respectively connected to its own drain, the gate of the MOS tube M2, and the gate of the MOS tube M16. The drain of the MOS tube M1 is respectively connected to the gate and drain of the MOS tube M3. The source of the MOS tube M3 is grounded. The drain of the MOS tube M2 is connected to one end of the resistor R1 and provides a reference voltage signal V to the hysteresis comparison unit 1.2. REF The other end of the resistor R1 is grounded, and the drain of the MOS tube M16 inputs a reference current I to the temperature detection unit 1.3. REF2 .

[0048] Based on the circuit design of the above-mentioned mirror constant current unit 1.1, the current output by the drain of the MOS tube M2 and the drain of the MOS tube M16 mirrors the current output by the drain of the MOS tube M1, that is, Figure 2 The reference current I REF1 With the reference current I REF2 The MOS tube M2 provides the reference current I to the resistor R1. REF1 , get the reference voltage signal V REF , and the MOS tube M16 provides a reference current I to the diodes D1 and D2 REF2 , get the temperature detection voltage signal V T Specifically, the calculation formula of the reference current is: REF =(μ n C ox (W / L)1(V GS -V THN1 ) 2 ) / 2.

[0049] where μ n is the electron mobility, C ox is the gate oxide capacitance per unit area, W is the channel width, L is the channel length, V GS is the voltage between the gate and the source, V THN1 It is the threshold voltage of the MOS tube. As can be seen from the above, the mirror constant current unit 1.1 can accurately replicate the reference current that is not affected by temperature, I REF Determined by the device size. The reference voltage signal V REF =I REF1 ×R1, preferably, the resistor R1 uses a resistor with a low temperature drift coefficient to ensure that the reference voltage signal V REF Not affected by temperature.

[0050] Specifically, see Figure 1In the temperature detection protection circuit, the hysteresis comparison unit 1.2 includes MOS tube M4, MOS tube M5, MOS tube M6, MOS tube M7, MOS tube M8, MOS tube M9, MOS tube M10, MOS tube M11, MOS tube M12, MOS tube M13, MOS tube M14, and MOS tube M15. The sources of the MOS tube M5, the MOS tube M7, the MOS tube M8, the MOS tube M9, the MOS tube M10, and the drain of the MOS tube M4 are all connected to the power supply voltage. The gate of the MOS tube M5 is respectively connected to the drain and gate of the MOS tube M7, the gate of the MOS tube M8, the drain of the MOS tube M9, and the drain of the MOS tube M11. The drain of the MOS tube M5 is respectively connected to the drain and gate of the MOS tube M6 and the gate of the MOS tube M13. The gate of the MOS tube M15 is respectively connected to the drain and gate of the MOS tube M10, the drain of the MOS tube M8, the gate of the MOS tube M9, and the drain of the MOS tube M12. The drain of the MOS tube M15 is connected to the drain of the MOS tube M13. The drain of the MOS tube M15 is the output end OUT of the temperature protection signal. The drain of the MOS tube M14 is respectively connected to the source of the MOS tube M11 and the source of the MOS tube M12. The gate of the MOS tube M14 is connected to the gate of the MOS tube M4. The gate of the MOS tube M11 is connected to the mirror constant current unit 1.1 and receives a reference voltage signal. The gate of the MOS tube M12 is connected to the temperature detection unit 1.3 and receives a temperature detection voltage signal. The sources of the MOS tube M4, the MOS tube M6, the MOS tube M8, and the MOS tube M14 are all grounded.

[0051] Among them, the reference voltage signal V REF The input is the negative input terminal of the hysteresis comparison unit 1.2, the temperature detection voltage signal V T The input is the positive input terminal of the hysteresis comparison unit 1.2. The working state of the hysteresis comparison unit 1.2 is as follows:

[0052] See also Figure 2 , when V REF >V T , the MOS tubes M7 and M11 are turned on, the current is I11=I7=I14, the MOS tubes M12, M10, and M9 are turned off. The MOS tube M8 attempts to provide a current I8=[(W / L)8 / (W / L)7]*I14. T As the voltage I8 increases, the current I8 increases and flows entirely through the MOS tube M12, and at this time, the MOS tube M10 still has no current.

[0053] When the current I12 flowing through the MOS tube M12 is I8=[(W / L)8 / (W / L)7]*I7, it is a turning point, and thereafter the MOS tubes M9 and M10 have current. That is, at the turning point, there is a current I14=I11+I12, so I14=I11+[(W / L)8 / (W / L)7]*I11, that is, I11=[(W / L)7 / ((W / L)8+(W / L)7)]*I14. Since the positive feedback is greater than the negative feedback requirement (W / L)8>(W / L)7, I11<(I14 / 2). According to the current-voltage formula, V GS11 and V GS12 The differential voltage at the positive turning point is V TRP+ =V GS12 -V GS11 . V GS11 and V GS12 They are V of M11 and M12 respectively. GS Voltage, V TRP+ It is the turn-on threshold of the temperature protection of the temperature detection protection circuit of the present invention.

[0054] Similarly, when the temperature detection voltage signal V T Decline, at the negative turning point, I12=[(W / L) 10 / ((W / L) 10 +(W / L)9)]*I14, we can find V GS11 and V GS12 , then the differential voltage at the negative turning point is V TRP- =V GS12 -V GS11 , that is, V TRP- It is the temperature protection shut-off threshold of the temperature detection protection circuit of the present invention.

[0055] The temperature detection protection circuit of the present invention is based on the temperature sensitivity of the diode. The real-time temperature of the chip is collected by the diode and the hysteresis characteristic of the hysteresis comparison unit is used for temperature protection. When the internal temperature of the chip is higher than the opening threshold V TRP+ Corresponding to the temperature, the temperature protection circuit of the hysteresis comparison unit outputs a temperature protection signal to shut down the chip output, protecting the module and its application system. When the internal temperature of the chip drops to the shutdown threshold V TRP- Corresponding to the temperature, the temperature protection circuit of the hysteresis comparison unit outputs a temperature protection signal to restore the chip output, and the chip and its application system resume normal operation.

[0056] Preferably, in the temperature detection protection circuit, the MOS tube M1, MOS tube M2, MOS tube M5, MOS tube M7, MOS tube M8, MOS tube M9, MOS tube M10, MOS tube M15, and MOS tube M16 are all N-channel depletion-type field-effect transistors, and the MOS tube M3, MOS tube M4, MOS tube M6, MOS tube M11, MOS tube M12, MOS tube M13, and MOS tube M14 are all P-channel depletion-type field-effect transistors.

[0057] See also Figure 2 The present invention also provides a high-voltage integrated chip, including the temperature detection protection circuit 1, the filter shaping circuit 2, the dead zone interlocking circuit 3, the fault logic control circuit 4, the high-side driving circuit 5, and the bootstrap circuit 6 as described above, wherein the filter shaping circuit 2 is connected to the high-side driving circuit 5 through the dead zone interlocking circuit 3, the temperature detection protection circuit 1 is connected to the high-side driving circuit 5 through the fault logic control circuit 4, and the bootstrap circuit 6 is connected to the high-side driving circuit 5. The dead zone interlocking circuit 3 is used to protect the circuit and its system, the bootstrap circuit 6 is used to provide a bootstrap voltage for the high-order driving pulse signal output by the high-side driving circuit 5, and the fault logic control circuit 4 is used to output fault signals of different fault conditions to control or regulate the working state of the high-side driving circuit 5.

[0058] The high-voltage integrated chip in the prior art has a temperature protection circuit integrated inside, but lacks a temperature detection circuit. The chip temperature is mainly detected by an off-chip temperature detection circuit and a temperature detection signal is output to the temperature detection circuit to control the operation of the temperature detection circuit. If the off-chip temperature detection circuit fails, its output signal is significantly different from the actual value, which will cause a series of erroneous operations of the microcontroller receiving the temperature signal at the front end of the system, reducing the system's working efficiency, or failing to make a corresponding protection response in time, thereby further accumulating heat, damaging reliability, and ultimately causing chip failure.

[0059] The high-voltage integrated chip provided in the present application is internally integrated with the temperature detection protection circuit 1 as described above, and utilizes the temperature-sensitive characteristics of the diode to achieve high-precision detection of the temperature within the chip. Compared with the prior art, it simultaneously realizes the temperature detection and temperature protection functions, and there is no need to place an external temperature detection circuit on the chip. The temperature detection protection circuit outputs a temperature protection signal to the fault logic control circuit 4, and the fault logic control circuit 4 controls the temperature protection control of the high-side drive circuit 5 according to the temperature protection signal, thereby further improving the reliability of the high-voltage integrated chip.

[0060] Furthermore, the high-voltage integrated chip also includes a low-side drive circuit 7, which is respectively connected to the dead zone interlock circuit 3 and the fault logic control circuit 4; the low-side drive circuit 7 is used to output a low-bit drive signal and is protected by the dead zone interlock circuit 3 and the fault logic control circuit 4.

[0061] Furthermore, the high-voltage integrated chip also includes an overload protection circuit 8, which is connected to the fault logic control circuit 4; the overload protection circuit 8 can prevent the high-voltage integrated chip from burning or failing due to overload.

[0062] Furthermore, the high-voltage integrated chip further comprises an undervoltage protection circuit 9 , which is connected to the fault logic control circuit 4 to prevent the high-voltage integrated chip from malfunctioning due to undervoltage.

[0063] Furthermore, the high-voltage integrated chip also includes a fault output circuit 10, which is connected to the fault logic control circuit 4; the fault output circuit 10 is used to receive a fault signal output by an off-chip module to prevent the fault caused by the off-chip module from affecting the normal operation of the chip.

[0064] In summary, the present application provides a temperature detection protection circuit. Based on the temperature sensitivity of the diode and the constant current provided by the mirror constant current unit of the low temperature drift coefficient, the temperature detection unit collects the real-time temperature in the chip through the diode and converts it into a temperature detection voltage signal, and uses the hysteresis characteristics of the hysteresis comparison unit for temperature protection. When the internal temperature of the chip is higher than the temperature corresponding to the turn-on threshold VTRP+, the temperature protection circuit of the hysteresis comparison unit outputs a temperature protection signal to shut down the chip output, protecting the module and its application system. When the internal temperature of the chip drops to the temperature corresponding to the turn-off threshold VTRP-, the temperature protection circuit of the hysteresis comparison unit outputs a temperature protection signal to restore the chip output, and the chip and its application system resume normal operation. At the same time, the present application also provides a high-voltage integrated chip, which is integrated with the temperature detection protection circuit as described above, and uses the temperature sensitivity of the diode to achieve high-precision detection of the temperature inside the chip. Compared with the prior art, it realizes the temperature detection and temperature protection functions at the same time, without the need for an external temperature detection circuit on the chip. The temperature detection protection circuit outputs a temperature protection signal to the fault logic control circuit, and the fault logic control circuit controls the temperature protection control of the high-side drive circuit according to the temperature protection signal, further improving the reliability of the high-voltage integrated chip.

[0065] It is understandable that those skilled in the art can make equivalent substitutions or changes based on the technical solution and inventive concept of the present invention, and all these changes or substitutions should fall within the protection scope of the claims attached to the present invention.

Claims

1. A temperature detection protection circuit, characterized in that: It includes a mirror constant current unit, a hysteresis comparison unit, and a temperature detection unit. The temperature detection unit includes at least two diodes. The mirror constant current unit provides a reference voltage signal to the hysteresis comparison unit and provides a reference current to the temperature detection unit. The temperature detection unit feeds back a temperature detection voltage signal to the hysteresis comparison unit based on the reference current and temperature change. The hysteresis comparison unit compares the reference voltage signal with the temperature detection voltage signal to output a temperature protection signal for controlling the operation of the chip.

2. The temperature detection protection circuit according to claim 1, characterized in that: The temperature detection unit includes a diode D1 and a diode D2, the diode D1 and the diode D2 are connected in series in the forward direction, the reference current provided by the mirror constant current unit is input into the positive electrode of the diode D1, the positive electrode of the diode D1 is connected to the hysteresis comparison unit and feeds back a temperature detection voltage signal, and is grounded to the negative electrode of the diode D2.

3. The temperature detection protection circuit according to claim 2, characterized in that: The mirror constant current unit includes a MOS tube M1, a MOS tube M2, a MOS tube M3, a MOS tube M16, and a resistor R1. The sources of the MOS tube M1, the MOS tube M2, and the MOS tube M16 are all connected to the power supply voltage. The gate of the MOS tube M1 is respectively connected to its own drain, the gate of the MOS tube M2, and the gate of the MOS tube M16. The drain of the MOS tube M1 is respectively connected to the gate and the drain of the MOS tube M3. The source of the MOS tube M3 is grounded. The drain of the MOS tube M2 is connected to one end of the resistor R1 and provides a reference voltage signal to the hysteresis comparison unit. The other end of the resistor R1 is grounded. The drain of the MOS tube M16 inputs a reference current to the temperature detection unit.

4. The temperature detection protection circuit according to claim 3, characterized in that: The hysteresis comparison unit includes MOS tube M4, MOS tube M5, MOS tube M6, MOS tube M7, MOS tube M8, MOS tube M9, MOS tube M10, MOS tube M11, MOS tube M12, MOS tube M13, MOS tube M14, and MOS tube M15. The sources of the MOS tube M5, the MOS tube M7, the MOS tube M8, the MOS tube M9, the MOS tube M10, and the MOS tube M15 and the drain of the MOS tube M4 are all connected to the power supply voltage. The gate of the MOS tube M5 is respectively connected to the drain and gate of the MOS tube M7, the gate of the MOS tube M8, the drain of the MOS tube M9, and the drain of the MOS tube M11. The drain of the MOS tube M5 is respectively connected to the drain and gate of the MOS tube M6 and the gate of the MOS tube M13. The gate of the MOS tube M15 is respectively connected to the drain and gate of the MOS tube M10, the drain of the MOS tube M8, the gate of the MOS tube M9, and the drain of the MOS tube M12. The drain of the MOS tube M15 is connected to the drain of the MOS tube M13. The drain of the MOS tube M15 is the output end of the temperature protection signal. The drain of the MOS tube M14 is respectively connected to the source of the MOS tube M11 and the source of the MOS tube M12. The gate of the MOS tube M14 is connected to the gate of the MOS tube M4. The gate of the MOS tube M11 is connected to the mirror constant current unit and receives a reference voltage signal. The gate of the MOS tube M12 is connected to the temperature detection unit and receives a temperature detection voltage signal. The sources of the MOS tube M4, the MOS tube M6, the MOS tube M8, and the MOS tube M14 are all grounded.

5. The temperature detection protection circuit according to claim 4, characterized in that: The MOS tube M1, MOS tube M2, MOS tube M5, MOS tube M7, MOS tube M8, MOS tube M9, MOS tube M10, MOS tube M15, and MOS tube M16 are all N-channel depletion type field effect transistors, and the MOS tube M3, MOS tube M4, MOS tube M6, MOS tube M11, MOS tube M12, MOS tube M13, and MOS tube M14 are all P-channel depletion type field effect transistors.

6. A high voltage integrated chip, characterized in that: It includes a temperature detection protection circuit, a filter shaping circuit, a dead zone interlock circuit, a fault logic control circuit, a high-side drive circuit, and a bootstrap circuit as described in any one of claims 1 to 5, wherein the filter shaping circuit is connected to the high-side drive circuit via the dead zone interlock circuit, the temperature detection protection circuit is connected to the high-side drive circuit via the fault logic control circuit, and the bootstrap circuit is connected to the high-side drive circuit.

7. The high voltage integrated chip according to claim 6, characterized in that: It also includes a low-side driving circuit, which is connected to the dead zone interlocking circuit and the fault logic control circuit respectively.

8. The high-voltage integrated chip according to claim 6, characterized in that: It also includes an overload protection circuit, which is connected to the fault logic control circuit.

9. The high voltage integrated chip according to claim 6, characterized in that: It also includes an undervoltage protection circuit, which is connected to the fault logic control circuit.

10. The high voltage integrated chip according to claim 6, characterized in that: It also includes a fault output circuit, which is connected to the fault logic control circuit.

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