Noise suppression circuit, high-voltage integrated circuit and driving chip

Abstract

The invention discloses a noise suppression circuit, a high-voltage integrated circuit and a driving chip, the noise suppression circuit comprises a signal receiving unit, a noise detection unit, an RS trigger and an output unit, the input end of the signal receiving unit is used for receiving an external input signal, and the input end of the noise detection unit is used for detecting a driving signal; the first output end of the noise detection unit is connected with the drain end of the signal receiving unit and the R end of the RS trigger, the second output end of the noise detection unit is connected with the drain end of the signal receiving unit and the S end of the RS trigger, and the output end of the RS trigger is connected with the input end of the output unit. The output end of the output unit is used for outputting a driving signal; in the noise suppression circuit disclosed by the invention, the noise detection unit outputs the control signal to the RS trigger when detecting that the noise exists in the driving signal, the RS trigger then generates the shielding signal, and the width of the shielding signal is obviously greater than that of the noise main signal, so that the common-mode noise can be effectively eliminated.

Description

Technical Field

[0001] The present invention relates to the technical field of temperature detection circuit design, and particularly to a noise suppression circuit, a high-voltage integrated circuit, and a driver chip. Background Art

[0002] A high-voltage integrated circuit (HVIC) is an advanced semiconductor device that is responsible for converting the signals of a microcontroller into signals suitable for driving an insulated gate bipolar transistor or a metal-oxide-semiconductor field-effect transistor; the design and application of such integrated circuits are crucial in the field of power electronics, especially in scenarios that require precise control of high voltage and large current, such as industrial motor control, power conversion, and the electric drive system of electric vehicles.

[0003] The core function of HVIC is to convert control signals from the low-voltage domain to the high-voltage domain while providing necessary isolation and driving capabilities; to achieve this function, HVIC integrates a variety of electronic components, including PMOS and NMOS transistors, bipolar transistors, diodes, zener diodes, resistors, capacitors, etc.; these electronic components work together to build a complex circuit system including Schmitt triggers, low-voltage and high-voltage level converters, pulse generators, delay circuits, filter circuits, over-current protection, overheat protection, under-voltage lockout protection, and bootstrap circuits.

[0004] In the high-side drive circuit of HVIC, a single-pulse generation circuit is specifically used to generate pulses at the rising edge and falling edge of the input signal, and these pulses are used to drive DMOS transistors; the width of the pulses is usually in the range of several hundred nanoseconds to ensure an accurate correspondence between the HIN signal and the output signal.

[0005] However, traditional drive output circuits may generate noise during operation, and the noise problem is particularly obvious when the HO signal is at a low level; at this time, the voltage at the output terminal may rise instantaneously, and this phenomenon is called "voltage spike"; the existence of voltage spikes not only interferes with the normal operation of the circuit but also may pose a threat to the reliability of the system and even cause equipment damage.

[0006] It can be seen that the existing drive output circuits still need further optimization and enhancement in terms of noise processing. Summary of the Invention

[0007] In view of the deficiencies of the above-mentioned prior art, the purpose of the present invention is to provide a noise suppression circuit that can effectively eliminate common-mode noise and improve the anti-interference ability of the circuit.

[0008] To achieve the above purpose, the present invention adopts the following technical solutions:

[0009] A noise suppression circuit, comprising a signal receiving unit, a noise detection unit, an RS flip-flop, and an output unit. The input end of the signal receiving unit is used to receive an external input signal, and the input end of the noise detection unit is used to detect a driving signal. The first output end of the noise detection unit is respectively connected to the drain of the signal receiving unit and the R end of the RS flip-flop. The second output end of the noise detection unit is respectively connected to the drain of the signal receiving unit and the S end of the RS flip-flop. The output end of the RS flip-flop is connected to the input end of the output unit, and the output end of the output unit is used to output a driving signal.

[0010] In the noise suppression circuit described above, the noise detection unit includes a first detection part and a second detection part. The input end of the first detection part and the input end of the second detection part are respectively used to detect a driving signal. The output end of the first detection part is respectively connected to the drain of the signal receiving unit and the R end of the RS flip-flop. The output end of the second detection part is respectively connected to the drain of the signal receiving unit and the S end of the RS flip-flop.

[0011] In the noise suppression circuit described above, the first detection part includes a first resistor R1, a second resistor R2, a first capacitor C1, and a first field-effect transistor MP1. One end of the first resistor R1, one end of the second resistor R2, and the source of the first field-effect transistor MP1 are respectively used to detect a driving signal. The other end of the second resistor R2 is respectively connected to the gate of the first field-effect transistor MP1 and one end of the first capacitor C1. The drain of the first field-effect transistor MP1 is respectively connected to the other end of the first resistor R1, the drain of the signal receiving unit, and the R end of the RS flip-flop, and the other end of the first capacitor C1 is grounded.

[0012] In the noise suppression circuit described above, the second detection part includes a third resistor R3, a fourth resistor R4, a second capacitor C2, and a second field-effect transistor MP2. One end of the third resistor R3, one end of the fourth resistor R4, and the source of the second field-effect transistor MP2 are respectively used to detect a driving signal. The other end of the fourth resistor R4 is respectively connected to the gate of the second field-effect transistor MP2 and one end of the second capacitor C2. The drain of the second field-effect transistor MP2 is respectively connected to the other end of the third resistor R3, the drain of the signal receiving unit, and the S end of the RS flip-flop, and the other end of the second capacitor C2 is grounded.

[0013] In the described noise suppression circuit, the signal receiving unit includes a first power transistor LDM1 and a second power transistor LDM2. The gates of the first power transistor LDM1 and the second power transistor LDM2 are respectively used to receive an external input signal. The drain of the first power transistor LDM1 is connected to the other end of the first resistor R1, the drain of the first field-effect transistor MP1, and the R terminal of the RS flip-flop. The drain of the second power transistor LDM2 is respectively connected to the other end of the third resistor R3, the drain of the second field-effect transistor MP2, and the S terminal of the RS flip-flop.

[0014] In the described noise suppression circuit, the output unit includes a driving part and an amplifying part. The input end of the driving part is connected to the Q terminal of the RS flip-flop. The positive end and the negative end of the driving part are respectively connected to the input end of the detection unit. The output end of the driving part is connected to the input end of the amplifying part. The negative end of the driving part and the control end of the amplifying part are respectively used to output a driving signal.

[0015] In the described noise suppression circuit, the driving part includes an output operational amplifier. The input end of the output operational amplifier is connected to the Q terminal of the RS flip-flop. The positive end and the negative end of the output operational amplifier are respectively connected to the input end of the detection unit. The output end of the output operational amplifier is connected to the input end of the amplifying part.

[0016] In the described noise suppression circuit, the amplifying part includes a common-emitter transistor. The base of the common-emitter transistor is connected to the output end of the output operational amplifier. The emitter of the common-emitter transistor is used to output a driving signal. The collector of the common-emitter transistor is used to connect to an external power supply device.

[0017] The present invention also correspondingly provides a high-voltage integrated circuit, including an RC filter circuit, a Schmitt circuit, a filter circuit, a level conversion circuit, a dead zone interlock circuit, a pulse circuit, and any one of the above-described noise suppression circuits. The input end of the RC filter circuit is used to receive an input signal. The output end of the RC filter circuit, the Schmitt circuit, the filter circuit, the level conversion circuit, the dead zone interlock circuit, and the input end of the pulse circuit are connected in sequence. The output end of the pulse circuit is connected to the input end of the noise suppression circuit. The output end of the noise suppression circuit is used to output a driving pulse signal.

[0018] The present invention also correspondingly provides a driving chip, on which the above-described high-voltage integrated circuit is integrated.

[0019] Beneficial effects:

[0020] The present invention provides a noise suppression circuit, including a noise detection unit. The noise detection unit is responsible for detecting the noise of the drive signal. When noise is detected, the noise detection unit sends a control signal to the RS flip-flop, causing the RS flip-flop to generate a shielding signal. The bandwidth of this shielding signal is significantly larger than the width of the main noise signal, that is, the duration of this shielding signal is significantly longer than the main noise signal, so as to ensure effective suppression of common-mode noise, thereby improving the anti-interference ability of the circuit and ensuring the safe and reliable operation of the drive chip. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a circuit block diagram of the noise suppression circuit provided by the present invention;

[0022] Figure 2 It is a circuit schematic diagram of the noise suppression circuit provided by the present invention;

[0023] Figure 3 It is a circuit structure diagram of the high-voltage integrated circuit provided by the present invention.

[0024] Description of main component symbols: 1 - signal receiving unit, 2 - noise detection unit, 21 - first detection part, 22 - second detection part, 3 - RS flip-flop, 4 - output unit, 41 - drive part, 42 - amplification part, 51 - RC filter circuit, 52 - Schmidt circuit, 53 - filter circuit, 54 - level conversion circuit, 55 - dead zone interlock circuit, 56 - pulse circuit. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0025] The present invention provides a noise suppression circuit, a high-voltage integrated circuit and a drive chip. To make the purpose, technical solution and effect of the present invention clearer and more definite, the following takes examples with reference to the drawings to further elaborate on the present invention in detail.

[0026] In the description of the present invention, it should be understood that terms such as "installation" and "connection" should be understood in a broad sense. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0027] Please refer to Figure 1 and Figure 2, the present invention provides a noise suppression circuit, including a signal receiving unit 1, a noise detection unit 2, an RS flip-flop 3 and an output unit 4. The input end of the signal receiving unit 1 is used to receive an external input signal, and the input end of the noise detection unit 2 is used to detect a driving signal. The first output end of the noise detection unit 2 is respectively connected to the drain of the signal receiving unit 1 and the R end of the RS flip-flop 3. The second output end of the noise detection unit 2 is respectively connected to the drain of the signal receiving unit 1 and the S end of the RS flip-flop 3. The output end of the RS flip-flop 3 is connected to the input end of the output unit 4, and the output end of the output unit 4 is used to output a driving signal.

[0028] This application discloses a noise suppression circuit, including a noise detection unit 2. The noise detection unit 2 is responsible for detecting noise in the driving signal. When noise is detected, the noise detection unit 2 sends a control signal to the RS flip-flop 3, causing the RS flip-flop 3 to generate a shielding signal. The bandwidth of this shielding signal is significantly larger than the width of the main noise signal, that is, the duration of this shielding signal is significantly longer than the main noise signal, to ensure that common-mode noise can be effectively suppressed, thereby improving the anti-interference ability of the circuit and ensuring that the driving chip can operate safely and reliably.

[0029] In this embodiment, the external input signal is a signal output by a pulse circuit 56 in a high-voltage integrated circuit, including a SET signal and a RESET signal.

[0030] Further, please refer to Figure 1 and Figure 2 , the noise detection unit 2 includes a first detection part 21 and a second detection part 22. The input ends of the first detection part 21 and the second detection part 22 are respectively used to detect the driving signal. The output end of the first detection part 21 is respectively connected to the drain of the signal receiving unit 1 and the R end of the RS flip-flop 3. The output end of the second detection part 22 is respectively connected to the drain of the signal receiving unit 1 and the S end of the RS flip-flop 3.

[0031] Further, please refer to Figure 2 , the first detection part 21 includes a first resistor R1, a second resistor R2, a first capacitor C1 and a first field-effect transistor MP1. One end of the first resistor R1, one end of the second resistor R2 and the source of the first field-effect transistor MP1 are respectively used to detect the driving signal; the other end of the second resistor R2 is respectively connected to the gate of the first field-effect transistor MP1 and one end of the first capacitor C1; the drain of the first field-effect transistor MP1 is respectively connected to the other end of the first resistor R1, the drain of the signal receiving unit 1 and the R end of the RS flip-flop 3, and the other end of the first capacitor C1 is grounded.

[0032] Further, please refer to Figure 2 , the second detection unit 22 includes a third resistor R3, a fourth resistor R4, a second capacitor C2, and a second field effect transistor MP2. One end of the third resistor R3, one end of the fourth resistor R4, and the source electrode of the second field effect transistor MP2 are respectively used to detect the drive signal; the other end of the fourth resistor R4 is respectively connected to the gate of the second field effect transistor MP2 and one end of the second capacitor C2; the drain of the second field effect transistor MP2 is respectively connected to the other end of the third resistor R3, the drain end of the signal receiving unit 1, and the S end of the RS flip-flop 3, and the other end of the second capacitor C2 is grounded.

[0033] In the first detection unit 21 and the second detection unit 22 disclosed in this embodiment, by using the classical resistor voltage division principle and combining with the high-sensitivity switching characteristics of the field effect transistor, the detection unit can accurately capture the minute changes of the drive signal. Whether it is the rising edge or the falling edge of the signal, it can be accurately detected and transmitted to the RS flip-flop 3, providing a solid foundation for the stable operation of the noise suppression circuit; further, the introduction of the capacitive element enables the detection unit to smooth out high-frequency noise and instantaneous fluctuations during the signal transmission process, greatly improving the anti-interference ability of the circuit and ensuring the accuracy and reliability of the signal output to the RS flip-flop 3.

[0034] Further, please refer to Figure 2 , the signal receiving unit 1 includes a first power transistor LDM1 and a second power transistor LDM2. The gates of the first power transistor LDM1 and the second power transistor LDM2 are respectively used to receive external input signals. The drain of the first power transistor LDM1 is connected to the other end of the first resistor R1, the drain of the first field effect transistor MP1, and the R end of the RS flip-flop 3. The drain of the second power transistor LDM2 is respectively connected to the other end of the third resistor R3, the drain of the second field effect transistor MP2, and the S end of the RS flip-flop 3.

[0035] In this embodiment, the first power transistor LDM1 and the second power transistor LDM2 are laterally diffused metal oxide semiconductor field effect transistors. Compared with traditional MOSFETs, the current of the LDMOS transistor flows laterally. This structural design is beneficial for working at a higher voltage and can withstand a larger power at the same time; the channel is formed by a double diffusion process, which can accurately control the channel length and doping concentration, thereby achieving good electrical performance and reliability.

[0036] Further, please refer to Figure 1 and Figure 2, the output unit 4 includes a driving part 41 and an amplifying part 42. The input end of the driving part 41 is connected to the Q end of the RS flip-flop 3. The positive end and the negative end of the driving part 41 are respectively connected to the input end of the detection unit. The output end of the driving part 41 is connected to the input end of the amplifying part 42. The negative end of the driving part 41 and the control end of the amplifying part 42 are respectively used for outputting driving signals.

[0037] Further, please refer to Figure 2 , the driving part 41 includes an output operational amplifier. The input end of the output operational amplifier is connected to the Q end of the RS flip-flop 3. The positive end and the negative end of the output operational amplifier are respectively connected to the input end of the detection unit. The output end of the output operational amplifier is connected to the input end of the amplifying part 42.

[0038] Further, please refer to Figure 2 , the amplifying part 42 includes a common-emitter transistor. The base of the common-emitter transistor is connected to the output end of the output operational amplifier. The emitter of the common-emitter transistor is used for outputting a driving signal. The collector of the common-emitter transistor is used for connecting an external power supply device.

[0039] In this embodiment, the external power supply device is the operating voltage VCC of a high-voltage integrated circuit; the common-emitter transistor is a common-emitter diode of a triode, and the diode is connected to the collector and the base of the triode.

[0040] In this embodiment, the output end of the driving part 41 is connected to the input end of the amplifying part 42, so that the amplifying part 42 can efficiently amplify the signal output by the driving part 41. Through this cascaded amplification method, the driving ability of the output driving signal is significantly enhanced, ensuring that the signal can remain stable and reliable during transmission and avoiding performance degradation caused by signal attenuation; specifically, the driving part 41 uses an output operational amplifier as the core component. The output operational amplifier not only has the characteristics of high gain and low noise, but also can provide a stable signal output in a wide frequency band range. This choice significantly improves the stability and reliability of the signal; while the amplifying part 42 uses a classic common-emitter transistor as the amplifying component. The common-emitter transistor can effectively amplify the input signal and output a stable and strong driving signal with its excellent characteristics such as high amplification factor, large input impedance, and small output impedance.

[0041] The noise suppression circuit disclosed in the present application can significantly enhance the stability and anti-interference ability of the circuit. On the basis of the traditional output drive circuit, the noise suppression circuit disclosed in the present application introduces two detection parts; wherein, the first detection part 21 accurately collects the interference signal dv / dt through the series combination of the second resistor R2 and the first capacitor C1; the first field effect transistor MP1 plays a key role in this process, and it timely feeds back the collected interference signal to the R end of the RS trigger 3, thereby effectively suppressing the noise; the second detection part 22 is connected in series by the fourth resistor R4 and the second capacitor C2, and the noise suppression effect is further enhanced through the accurate collection and feedback of the second field effect transistor MP2; in the core part of the circuit, the two LDMOS tubes LDM1 and LDM2 play a vital role. When the input signal is maintained at a low level, the pulse circuit 56 will not emit Pulse signal, at this time, the gate potential of LDM1 and LDM2 remains at a low potential and is in a stable off state, ensuring that the static power consumption of the circuit is minimized; when the drive motor starts and enters the working state, if the HO signal is 0, the VS voltage will be raised accordingly; at this time, the waveform displacement current at points A, B, C, and D produces a voltage reduction through the resistor. This series of delicate charge flow processes ensures the stable operation of the circuit; when the noise suppression circuit keenly detects the noise dv / dt, the field effect tubes MP1 and MP2 are quickly turned on, and the potentials at points A and B quickly follow the changes of VB. The voltage at point B is significantly higher than that at point A, making the shielding signal width generated by RS trigger 3 significantly larger than the width of the noise main signal, effectively suppressing the interference of noise, that is, effectively eliminating common-mode noise, ensuring that the HO output always remains at a low level, and ensuring the stability and reliability of the circuit.

[0042] See also Figure 3 The present invention also provides a high-voltage integrated circuit accordingly, including an RC filter circuit 5351, a Schmitt circuit 52, a filter circuit 53, a level conversion circuit 54, a dead zone interlocking circuit 55, a pulse circuit 56 and any of the above-mentioned noise suppression circuits, wherein the input end of the RC filter circuit 5351 is used to receive an input signal, the output end of the RC filter circuit 5351, the Schmitt circuit 52, the filter circuit 53, the level conversion circuit 54, the dead zone interlocking circuit 55 and the input end of the pulse circuit 56 are connected in sequence, the output end of the pulse circuit 56 is connected to the input end of the noise suppression circuit, and the output end of the noise suppression circuit is used to output a driving pulse signal.

[0043] The present invention also provides a driver chip accordingly, on which the high-voltage integrated circuit as described above is integrated.

[0044] It is understandable that those of ordinary skill in the art can make equivalent substitutions or changes based on the technical solution of the present invention and its inventive concept, and all such changes or substitutions should fall within the protection scope of the present invention.

Claims

1. A noise suppression circuit, characterized in that: It includes a signal receiving unit, a noise detection unit, an RS trigger and an output unit, wherein the input end of the signal receiving unit is used to receive an external input signal, the input end of the noise detection unit is used to detect a driving signal, the first output end of the noise detection unit is respectively connected to the drain end of the signal receiving unit and the R end of the RS trigger, the second output end of the noise detection unit is respectively connected to the drain end of the signal receiving unit and the S end of the RS trigger, the output end of the RS trigger is connected to the input end of the output unit, and the output end of the output unit is used to output a driving signal.

2. A noise suppression circuit according to claim 1, characterized in that: The noise detection unit includes a first detection unit and a second detection unit, the input end of the first detection unit and the input end of the second detection unit are respectively used to detect the driving signal, the output end of the first detection unit is respectively connected to the drain end of the signal receiving unit and the R end of the RS trigger, and the output end of the second detection unit is respectively connected to the drain end of the signal receiving unit and the S end of the RS trigger.

3. A noise suppression circuit according to claim 2, characterized in that: The first detection unit includes a first resistor R1, a second resistor R2, a first capacitor C1 and a first field effect transistor MP1, one end of the first resistor R1, one end of the second resistor R2 and the source of the first field effect transistor MP1 are respectively used to detect the driving signal; the other end of the second resistor R2 is respectively connected to the gate of the first field effect transistor MP1 and one end of the first capacitor C1; the drain of the first field effect transistor MP1 is respectively connected to the other end of the first resistor R1, the drain end of the signal receiving unit and the R end of the RS trigger, and the other end of the first capacitor C1 is grounded.

4. A noise suppression circuit according to claim 3, characterized in that: The second detection unit includes a third resistor R3, a fourth resistor R4, a second capacitor C2 and a second field effect transistor MP2, one end of the third resistor R3, one end of the fourth resistor R4 and the source of the second field effect transistor MP2 are respectively used to detect the driving signal; the other end of the fourth resistor R4 is respectively connected to the gate of the second field effect transistor MP2 and one end of the second capacitor C2; the drain of the second field effect transistor MP2 is respectively connected to the other end of the third resistor R3, the drain end of the signal receiving unit and the S end of the RS trigger, and the other end of the second capacitor C2 is grounded.

5. A noise suppression circuit according to claim 4, characterized in that: The signal receiving unit includes a first power tube LDM1 and a second power tube LDM2, the gate of the first power tube LDM1 and the gate of the second power tube LDM2 are respectively used to receive external input signals, the drain of the first power tube LDM1 is connected to the other end of the first resistor R1, the drain of the first field effect tube MP1 and the R end of the RS trigger, and the drain of the second power tube LDM2 is respectively connected to the other end of the third resistor R3, the drain of the second field effect tube MP2 and the S end of the RS trigger.

6. The noise suppression circuit according to claim 1, characterized in that: The output unit includes a driving part and an amplifier part, the input end of the driving part is connected to the Q end of the RS trigger, the positive end and the negative end of the driving part are respectively connected to the input end of the detection unit, the output end of the driving part is connected to the input end of the amplifier part, and the negative end of the driving part and the control end of the amplifier part are respectively used to output driving signals.

7. A noise suppression circuit according to claim 6, characterized in that: The driving unit includes an output operational amplifier, the input end of the output operational amplifier is connected to the Q end of the RS trigger, the positive end and the negative end of the output operational amplifier are respectively connected to the input end of the detection unit, and the output end of the output operational amplifier is connected to the input end of the amplifying unit.

8. A noise suppression circuit according to claim 7, characterized in that: The amplifying part comprises a common-emitter tube, the base of the common-emitter tube is connected to the output end of the output operational amplifier, the emitter of the common-emitter tube is used to output a driving signal, and the collector of the common-emitter tube is used to connect to an external power supply device.

9. A high voltage integrated circuit, characterized in that: It includes an RC filtering circuit, a Schmitt circuit, a filtering circuit, a level conversion circuit, a dead zone interlocking circuit, a pulse circuit and a noise suppression circuit as described in any one of claims 1 to 8, wherein the input end of the RC filtering circuit is used to receive an input signal, the output end of the RC filtering circuit, the Schmitt circuit, the filtering circuit, the level conversion circuit, the dead zone interlocking circuit and the input end of the pulse circuit are connected in sequence, the output end of the pulse circuit is connected to the input end of the noise suppression circuit, and the output end of the noise suppression circuit is used to output a driving pulse signal.

10. A driver chip, characterized in that: The driving chip is integrated with a high-voltage integrated circuit as claimed in claim 9.

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