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CN-115756081-B - Voltage stabilizing circuit based on current feedback

CN115756081BCN 115756081 BCN115756081 BCN 115756081BCN-115756081-B

Abstract

The invention discloses a voltage stabilizing circuit based on current feedback, which comprises a sampling module, an adjusting module and a feedback control module, and particularly comprises a high-voltage MOS tube HV_PM1, a high-voltage MOS tube HV_PM2, a high-voltage MOS tube HV_PM3, a high-voltage MOS tube HV_NM1, a normal-voltage MOS tube NM1, a normal-voltage MOS tube NM2, a normal-voltage MOS tube NM3, a normal-voltage MOS tube NM4, a voltage stabilizing diode Z1, a resistor R0, a resistor R1, a resistor R3, a bias current I1, a bias current I2 and a bias current I3. When the input voltage is lower than the reverse breakdown voltage V Z1 of the voltage stabilizing diode Z1, the output voltage is equal to the input voltage, the voltage drop is small, and when the input voltage is high, the gate-source voltage difference of the MOS tube is adjusted through a feedback loop by sampling the current flowing through the voltage stabilizing diode Z1, so that the on-resistance of the MOS tube is changed, and the output voltage VOUT is stabilized at the reverse breakdown voltage V Z1 of one voltage stabilizing diode Z1, about 5.5V.

Inventors

  • LI WENJIA
  • LIU HAO
  • LUO CHENG
  • QUAN LEI
  • YANG YUE

Assignees

  • 无锡中微爱芯电子有限公司

Dates

Publication Date
20260505
Application Date
20221207

Claims (8)

  1. 1. The voltage stabilizing circuit based on current feedback is characterized by comprising a sampling module (201), an adjusting module (202) and a feedback control module (203), and specifically comprises a MOS tube HV_PM1, a MOS tube HV_PM2, a MOS tube HV_PM3 and a MOS tube HV_NM1, a MOS tube NM1, a MOS tube NM2, a MOS tube NM3 and a MOS tube NM4, a voltage stabilizing diode Z1, a resistor R0, a resistor R1 and a resistor R2, a bias current I1, a bias current I2 and a bias current I3; the adjusting module (202) only comprises the MOS tube HV_PM3, and the grid electrode of the MOS tube HV_PM3 is connected with the resistor R0 in the feedback control module (203) at a point C; The sampling module (201) comprises a bias current I2, a bias current I3 and a zener diode Z1 which are connected with an output voltage VOUT, wherein the bias current I3 is connected with a grid electrode and a drain electrode of an MOS tube NM4, a source electrode of the MOS tube NM4 is connected with a resistor R2 in series, the bias current I2 is connected with the drain electrode of the MOS tube NM3, a grid electrode of the MOS tube NM3 is connected with a grid electrode of the MOS tube NM4, the drain electrode of the MOS tube NM3 is connected with a resistor R1 in series, and an anode of the zener diode Z1 is connected with the resistor R1 in series and is connected with a point A; The feedback control module (203) comprises a resistor R0 and a MOS tube HV_PM2 which are connected with an input voltage VIN, wherein the resistor R0 and the MOS tube HV_PM2 are connected in parallel and then connected with a bias current I1 at a point C, a drain electrode of the MOS tube HV_PM2 and the bias current I1 are connected with the point C, a grid electrode of the MOS tube HV_PM2 and a grid electrode and a drain electrode of the MOS tube HV_PM1 are respectively and electrically connected, a drain electrode of the MOS tube HV_PM1 and a drain electrode of the MOS tube HV_NM1 are electrically connected, a source electrode of the MOS tube HV_NM1 and a drain electrode of the MOS tube NM1 are electrically connected, a grid electrode of the MOS tube NM1 and a grid electrode of the MOS tube NM2 are connected with a drain electrode of the MOS tube NM3 in the sampling module (201); The voltage stabilizing circuit based on current feedback comprises an input voltage VIN, GND and an output voltage VOUT, wherein the input voltage VIN is the power supply voltage of a chip, and the input voltage range is large, the bias current I3 and the bias current I2 are bias currents of nA level, and the bias current I1 is bias current of uA level, wherein I3=12 < I1, R2=R1 < R0; The source electrode of the MOS tube HV_PM3 is electrically connected with the input voltage VIN, the drain electrode of the MOS tube HV_PM3 is electrically connected with the output voltage VOUT, the other end of the resistor R2 is electrically connected with the GND, the other end of the resistor R1 is electrically connected with the GND, the bias current I1 is output to the GND, the source electrode of the MOS tube HV_PM2 is electrically connected with the input voltage VIN, the source electrode of the MOS tube HV_PM1 is electrically connected with the input voltage VIN, the grid electrode of the MOS tube HV_NM1 is electrically connected with the output voltage VOUT, the source electrode of the MOS tube NM1 is electrically connected with the GND, and the source electrode of the MOS tube NM2 is electrically connected with the GND.
  2. 2. The voltage regulator circuit according to claim 1, wherein the adjustment module (202) receives the input voltage VIN and adjusts the output voltage VOUT, and wherein the sampling module (201) samples a current signal from the output voltage VOUT through the zener diode Z1.
  3. 3. The voltage stabilizing circuit based on current feedback according to claim 2, wherein said feedback control module (203) controls said adjusting module (202) to adjust voltage according to the sampled current signal of said sampling module (201) so as to stabilize the output voltage.
  4. 4. The voltage stabilizing circuit based on current feedback according to claim 1, wherein a capacitor C1 is electrically connected between the output voltage VOUT and GND, and the capacitor C1 is used for reducing ripple of the output voltage VOUT.
  5. 5. The voltage stabilizing circuit based on current feedback according to claim 1, wherein the MOS transistor HV_PM1, the MOS transistor HV_PM2, the MOS transistor HV_PM3 and the MOS transistor HV_NM1 belong to high-voltage transistors, and the MOS transistor NM1, the MOS transistor NM2, the MOS transistor NM3 and the MOS transistor NM4 belong to normal-voltage transistors.
  6. 6. The current feedback based voltage regulator circuit of claim 1, wherein: when the voltage of the input voltage VIN is lower and smaller than the reverse breakdown voltage VZ1 of the zener diode Z1, the zener diode Z1 is not turned on, i.e. no current flows through the zener diode Z1, the currents flowing through the MOS transistor NM3 and the MOS transistor NM2 are I2a and I2b, respectively, and i2=i2a+i2b, because i3=i2, the MOS transistor NM3 and the NM4 have the same size, at this time, most of the current in the bias current I2 flows through the MOS transistor NM3, i.e. I2a splits off most of the current in the bias current I2, the voltages at both ends of the resistor R1 and the resistor R2 are approximately equal, i.e. VA is approximately equal to VB, the current I2b of the MOS transistor NM2 in the feedback control module (203) is small, the current Ip mirrored to the MOS transistor hv_pm2 through the MOS transistor NM1 and the MOS transistor hv_pm1 is also very small, since the current Ip flowing through the MOS transistor hv_pm2 is very small, and i1=ip+ir, most of the bias current I1 flows through the resistor R0, the voltage difference VIN-VC between two ends of the resistor R0 is large, that is, the voltage difference VIN-VC between the gate and source of the MOS transistor hv_pm3 in the adjustment module (202) is large, at this time, the MOS transistor hv_pm3 operates in a linear region, for a MOS transistor with a certain size, the on-resistance of the MOS transistor is inversely proportional to the voltage difference between the gate and source, that is, the larger the voltage difference between the gate and source is, the smaller the on-resistance is, so when the input voltage VIN is smaller than the reverse breakdown voltage VZ1 of the voltage stabilizing diode Z1, the voltage difference between the gate and source of the MOS transistor hv_pm3 is larger, the output voltage VOUT is approximately equal to the input voltage VIN.
  7. 7. The voltage stabilizing circuit based on current feedback according to claim 1, wherein the voltage of the input voltage VIN increases, the output voltage VOUT follows the rise of the input voltage VIN, when the output voltage VOUT exceeds the regulated voltage VZ1 of the regulated diode Z1, current flows through the regulated diode Z1, so that the voltage difference between two ends of the resistor R1 is increased, namely VA increases, because the MOS tube NM3 and the MOS tube NM4 are connected by a current mirror, the gate voltage of the MOS tube NM3 is clamped at a constant value, VA increases to cause the gate source voltage thereof to decrease, so that the current I2a flowing through the MOS tube NM3 becomes smaller, the current I2b flowing through the MOS tube NM2 in the feedback control module (203) becomes larger, the current Ip mirrored to the MOS tube HV_PM2 through the MOS tube NM1 and the MOS tube HV_PM1 becomes larger, the bias current I1 only flows through a small part of the MOS tube NM3 and the MOS tube NM1 becomes smaller, the voltage difference between two ends of the resistor Vc 0 and the MOS tube Vc_PM2 becomes smaller, and the voltage difference between two ends of the MOS tube Vc_PM0 becomes smaller, and the voltage difference between the voltage between the MOS tube Vc and the voltage is regulated.
  8. 8. The voltage stabilizing circuit based on current feedback according to claim 1, wherein when the input voltage VIN is always greater than the reverse breakdown voltage VZ1 of the voltage stabilizing diode Z1, when the output voltage VOUT exceeds VZ1, a current flows in the voltage stabilizing diode Z1, the output voltage VOUT is reduced through feedback, when the output voltage VOUT is reduced to be less than the reverse breakdown voltage VZ1 of the voltage stabilizing diode Z1, no current flows in the voltage stabilizing diode Z1, the gate-source voltage difference of the MOS transistor hv_pm3 is increased through the feedback control module (203), the output voltage VOUT starts to rise again, and thus repeatedly, the gate-source voltage difference of the MOS transistor hv_pm3 is adjusted through a feedback loop by sampling the current magnitude of the voltage flowing in the voltage stabilizing diode Z1, so that the output voltage VOUT fluctuates around the reverse breakdown voltage VZ1 of the voltage stabilizing diode Z1, and a voltage of about 5.5V is obtained.

Description

Voltage stabilizing circuit based on current feedback Technical Field The invention belongs to the technical field of electronic circuits, and particularly relates to a voltage stabilizing circuit based on current feedback. Background The voltage stabilizing circuit is a circuit which can still keep the output voltage constant when the input voltage and the output load change, and is widely applied to various electronic equipment. The existing voltage stabilizing circuit is used for obtaining constant output voltage, meanwhile, larger load capacity and larger input voltage range are needed, the circuit structure is complex, the power consumption is larger, and certain requirements are met on the manufacturing process. In the prior art, in the medium and small power grid driving circuit, the devices such as a normal pressure tube, a high pressure tube, a power tube and the like are mostly thin grid oxide devices, and the voltage withstand value of a grid source electrode is about 5.5V. The smaller the on-resistance of the power tube in the grid driving circuit is, the better the on-resistance of the power tube is, at a certain size of the power tube, the inversely proportional to the overdrive voltage (VGS-VTH), namely, the higher the grid source voltage is, the smaller the on-resistance is, the smaller the on-loss is, and meanwhile, the grid source Voltage (VGS) cannot exceed the grid source withstand voltage value of the power tube, so that the drive circuit needs to be powered by generating a voltage as high as possible on the premise of not exceeding the grid source withstand voltage value of the device. In a gate driving circuit, an input voltage range is large, and in order to realize stable and reliable power supply, a voltage stabilizing circuit with a simple structure and a wide input range needs to be designed, wherein when the input voltage is lower than a device withstand voltage (5.5V), an output voltage is approximately equal to the input voltage, a voltage drop is small, and when the input voltage is higher than the device withstand voltage (5.5V), the output voltage is stabilized at the device withstand voltage value (5.5V). The current voltage stabilizing circuit is realized by adopting a low dropout linear voltage stabilizer, as shown in fig. 1, has a larger input voltage range and larger load capacity, but the linear voltage stabilizer comprises an error amplifier, so that the circuit complexity is increased, and the design cost is high. The other is that a mode of combining a voltage stabilizing tube and a triode is adopted, the obtained output voltage is the voltage stabilizing tube voltage minus the conduction voltage VBE of the triode, namely the output voltage is not only dependent on the voltage stabilizing tube voltage, but also related to the conduction voltage of the triode, and meanwhile, a large resistor (megaohm level) needs to be connected in series with the voltage stabilizing tube for current limiting, the current can linearly increase along with the rising of an input power supply, and the static current can obviously increase at the time of high input power supply voltage. In summary, in the existing voltage stabilizing circuit, the circuit structure of the low dropout linear voltage regulator is complex, the design cost is high, the output variable is more influenced by the mode of combining the voltage stabilizing tube and the triode, and the static current can be linearly increased along with the rising of the input voltage. Therefore, the invention provides a voltage stabilizing circuit based on current feedback, which adopts a current feedback mode, has the output voltage approximately equal to the input voltage at the time of low input voltage and small voltage drop, and has the output voltage stabilized at about 5.5V (reverse breakdown voltage of a zener diode) at the time of high input voltage, and has the advantages of simple circuit structure, low manufacturing cost, small quiescent current and low power consumption, and is suitable for a circuit system needing about 5.5V constant voltage. Disclosure of Invention The present invention is directed to a voltage stabilizing circuit based on current feedback, so as to solve the problems set forth in the background art. The invention provides a voltage stabilizing circuit based on current feedback, which comprises a sampling module, an adjusting module and a feedback control module, and is composed of a MOS tube HV_PM1, a MOS tube HV_PM2, a MOS tube HV_PM3 and a MOS tube HV_NM1, a MOS tube NM1, a MOS tube NM2, a MOS tube NM3 and a MOS tube NM4, a voltage stabilizing diode Z1, a resistor R0, a resistor R1 and a resistor R3, a bias current I1, a bias current I2 and a bias current I3; the adjusting module only comprises the MOS tube HV_PM3, and the grid electrode of the MOS tube HV_PM3 is connected with the resistor R0 in the feedback control module at a point C; The sampling module comprises a bias current I2, a bias cu