CN113783160B - Undervoltage protection circuit and power module - Google Patents
Undervoltage protection circuit and power module Download PDFInfo
- Publication number
- CN113783160B CN113783160B CN202111330791.0A CN202111330791A CN113783160B CN 113783160 B CN113783160 B CN 113783160B CN 202111330791 A CN202111330791 A CN 202111330791A CN 113783160 B CN113783160 B CN 113783160B
- Authority
- CN
- China
- Prior art keywords
- voltage
- switching tube
- power supply
- comparison
- module
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000001514 detection method Methods 0.000 claims abstract description 45
- 238000005070 sampling Methods 0.000 claims abstract description 12
- 238000001914 filtration Methods 0.000 claims description 27
- 230000035945 sensitivity Effects 0.000 claims description 9
- 238000007493 shaping process Methods 0.000 claims description 5
- 238000010586 diagram Methods 0.000 description 12
- 238000011084 recovery Methods 0.000 description 5
- 239000003990 capacitor Substances 0.000 description 4
- 238000000034 method Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000010355 oscillation Effects 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
- H02H3/24—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to undervoltage or no-voltage
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H1/00—Details of emergency protective circuit arrangements
- H02H1/0007—Details of emergency protective circuit arrangements concerning the detecting means
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H7/00—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
- H02H7/10—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for converters; for rectifiers
- H02H7/12—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for converters; for rectifiers for static converters or rectifiers
- H02H7/1203—Circuits independent of the type of conversion
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Emergency Protection Circuit Devices (AREA)
Abstract
The application discloses undervoltage protection circuit and power module, undervoltage protection circuit includes: the voltage sampling and power supply module is used for collecting power supply voltage, outputting detection voltage and converting the power supply voltage into power supply voltage for internal power supply, wherein the power supply voltage is smaller than the power supply voltage; and the comparison module is connected with the voltage sampling and power supply module, compares the detected voltage with a reference and outputs a comparison signal, the comparison signal is used for controlling whether to supply power to a load, and the power supply voltage supplies power to the comparison module. The application provides an under-voltage protection circuit, voltage acquisition and power module generate be used for the inside power supply that is less than mains voltage's of under-voltage protection circuit power supply voltage, and then adopt the low-voltage tube can accomplish normal work among the circuit module by the power supply voltage power supply among the under-voltage protection circuit. And then reduced the use quantity of high-voltage tube in the undervoltage protection circuit, effectively reduced work consumption current, and reduced the circuit area.
Description
Technical Field
The present invention relates to the field of power electronics technologies, and in particular, to an under-voltage protection circuit and a power module.
Background
IPM (Intelligent Power Module) is a new type high-Power electronic device, which has the advantages of high current density, low saturation voltage and high voltage resistance, and is widely used in various fields such as air conditioners, washing machines and fans to drive the motor of the above-mentioned electric appliances.
Many integrated circuit units, semiconductor elements and other electronic devices are integrated in the intelligent power module, and in order to enable the electronic devices to work normally, the intelligent power module needs to be ensured to work under the environment of safe working voltage and working current. In practical application, an under-voltage protection circuit is arranged for detecting the power supply voltage and starting under-voltage protection in an under-voltage state so as to protect the intelligent power module. Fig. 1 shows a schematic structure diagram of an under-voltage protection circuit in the prior art, and as shown in fig. 1, the under-voltage protection circuit 500 at least includes a voltage acquisition module 510, a comparison module 520, a bias current generation module 530, and a reference voltage generation module 540. The voltage collecting module 510 collects a power voltage, the reference voltage generating module 540 generates a reference voltage, and the bias current generating module 530 is configured to provide a bias current to other modules. The voltage collecting module 510, the comparing module 520, the bias current generating module 530, and the reference voltage generating module 540 are all powered by a power supply voltage VCC. However, the power voltage VCC provided to the intelligent power module is high, and thus a large number of high-voltage power transistors are required in the under-voltage protection circuit 500 to receive the power voltage VCC, so as to maintain the normal operation of the under-voltage protection circuit 500, resulting in a large occupied area of the under-voltage protection circuit 500.
Disclosure of Invention
In view of the above problems, an object of the present invention is to provide an under-voltage driving circuit and a power module, which reduce the operation consumption and the circuit area, thereby further improving the reliability of the intelligent power module.
According to an aspect of the present invention, there is provided an under-voltage protection circuit, including:
the voltage sampling and power supply module is used for collecting power supply voltage, outputting detection voltage and converting the power supply voltage into power supply voltage for internal power supply, wherein the power supply voltage is smaller than the power supply voltage;
the comparison module is connected with the voltage sampling and power supply module, compares the detected voltage with a reference and outputs a comparison signal, the comparison signal is used for controlling whether to supply power to a load or not,
wherein the supply voltage supplies power to the comparison module.
Optionally, the voltage sampling and power supplying module includes:
the voltage acquisition unit outputs the detection voltage and provides a first bias current; and
and the voltage generating unit is connected with the voltage acquisition unit to receive the first bias current and convert the power supply voltage into the power supply voltage.
Optionally, the comparison module comprises:
the comparison unit is an open-loop comparison circuit in a band gap reference form and is used for performing reference comparison on the detection voltage;
the bias unit receives the supply voltage and is connected with the comparison unit to provide a second bias current and a third bias current; and
and the output unit is connected with the comparison unit and outputs the comparison signal based on a reference comparison result.
Optionally, the voltage acquisition unit includes:
a first switch tube, a first end receiving the power voltage, a second end connected with a control end and providing the first bias current;
the first end of the first resistor is connected with the second end of the first switching tube, and the second end of the first resistor is used as the output end of the voltage acquisition unit to output the detection voltage; and
and the first end of the second resistor is connected with the second end of the first resistor, and the second end of the second resistor is grounded.
Optionally, the voltage generation unit includes:
the control end of the second switching tube is connected with the control end of the first switching tube, and the first end of the second switching tube receives the power supply voltage;
the anode of the diode is connected with the second end of the second switching tube, and the cathode of the diode is grounded;
and the control end of the third switching tube is connected with the anode of the diode, the first end of the third switching tube receives the power supply voltage, and the second end of the third switching tube is used as the output end of the voltage generation unit to output the power supply voltage.
Optionally, the diode is a zener diode or a transistor short-circuited to the diode, the first switching tube and the second switching tube are P-type triodes or transistors, and the third switching tube is an N-type triode or transistor.
Optionally, the bias unit comprises:
a fourth switching tube, wherein the first end receives the power supply voltage, the control end is connected with the second end, and the second end outputs the second bias current;
a first end of the fifth switching tube receives the power supply voltage, a control end of the fifth switching tube is connected with a control end of the fourth switching tube, and a second end of the fifth switching tube outputs the third bias current;
and the first end of the sixth switching tube receives the power supply voltage, the control end of the sixth switching tube is connected with the second end of the sixth switching tube, and the second end of the sixth switching tube is also connected with the second end of the fifth switching tube.
Optionally, the comparing unit includes:
a third resistor;
a first end of the fourth resistor is connected with a second end of the third resistor, and the second end of the fourth resistor is grounded;
a seventh switch tube, a control end of which receives the detection voltage, a first end of which is connected with the bias unit to receive the second bias current, and a second end of which is connected with the first end of the third resistor;
and a control end of the eighth switching tube is connected with the control end of the seventh switching tube, a first end of the eighth switching tube is connected with the bias unit to receive the third bias current, and a second end of the eighth switching tube is connected with a first end of the fourth resistor.
Optionally, the sensitivity of the second bias current to voltage is less than the sensitivity of the third bias current to voltage.
Optionally, initial voltages of the control terminals of the seventh switching tube and the eighth switching tube are set to be reference voltages, the detection voltage is smaller than the reference voltages, the third bias current is smaller than the second bias current, and the comparison signal is in an active level state; the detection voltage is greater than the reference voltage, the third bias current is greater than the second bias current, and the comparison signal is in an invalid level state.
Optionally, the output unit includes:
and the control end of the ninth switching tube is connected with the first end of the eighth switching tube, the first end of the ninth switching tube receives the power supply voltage, and the second end of the ninth switching tube serves as the output end of the comparison module to output the comparison signal.
Optionally, the output of the comparison module further receives a load current.
Optionally, the output terminal of the voltage generation unit further receives a load current.
Optionally, the method further comprises:
and the filtering module is powered by the power supply voltage and is used for converting and shaping the waveform of the comparison signal to output an undervoltage protection signal.
Optionally, the filtering module includes:
the input end of the Schmitt trigger receives the comparison signal, and the output end of the Schmitt trigger outputs the undervoltage protection signal; and
and a filtering unit setting a filtering time based on the bias current and the capacitance.
Optionally, the voltage collecting unit further includes:
and the hysteresis window unit maintains or updates the voltage division coefficient of the voltage acquisition unit based on the undervoltage protection signal.
Optionally, when the under-voltage protection signal changes to an active level state, the voltage division coefficient remains unchanged; and under the condition that the undervoltage protection signal is changed into an invalid level state, the voltage division coefficient is updated.
Optionally, the hysteresis window unit includes:
a fifth resistor;
and the control end of the tenth switching tube receives the undervoltage protection signal, the first end of the tenth switching tube is connected with the first end of the fifth resistor and the voltage acquisition unit, and the second end of the tenth switching tube is connected with the second end of the fifth resistor and grounded.
According to another aspect of the present invention, there is provided a power module including an under-voltage protection circuit, the under-voltage protection circuit including:
the voltage sampling and power supply module is used for collecting power supply voltage, outputting detection voltage and converting the power supply voltage into power supply voltage for internal power supply, wherein the power supply voltage is smaller than the power supply voltage;
the comparison module is connected with the voltage sampling and power supply module, compares the detected voltage with a reference and outputs a comparison signal, the comparison signal is used for controlling whether to supply power to a load or not,
wherein the supply voltage supplies power to the comparison module.
Optionally, the voltage sampling and power supplying module includes:
the voltage acquisition unit outputs the detection voltage and provides a first bias current; and
and the voltage generating unit is connected with the voltage acquisition unit to receive the first bias current and convert the power supply voltage into the power supply voltage.
Optionally, the comparison module comprises:
the comparison unit is an open-loop comparison circuit in a band gap reference form and is used for performing reference comparison on the detection voltage;
the bias unit receives the supply voltage and is connected with the comparison unit to provide a second bias current and a third bias current; and
and the output unit is connected with the comparison unit and outputs the comparison signal based on a reference comparison result.
Optionally, the voltage acquisition unit includes:
a first switch tube, a first end receiving the power voltage, a second end connected with a control end and providing the first bias current;
the first end of the first resistor is connected with the second end of the first switching tube, and the second end of the first resistor is used as the output end of the voltage acquisition unit to output the detection voltage; and
and the first end of the second resistor is connected with the second end of the first resistor, and the second end of the second resistor is grounded.
Optionally, the voltage generation unit includes:
the control end of the second switching tube is connected with the control end of the first switching tube, and the first end of the second switching tube receives the power supply voltage;
the anode of the diode is connected with the second end of the second switching tube, and the cathode of the diode is grounded;
and the control end of the third switching tube is connected with the anode of the diode, the first end of the third switching tube receives the power supply voltage, and the second end of the third switching tube is used as the output end of the voltage generation unit to output the power supply voltage.
Optionally, the diode is a zener diode or a transistor short-circuited to the diode, the first switching tube and the second switching tube are P-type triodes or transistors, and the third switching tube is an N-type triode or transistor.
Optionally, the bias unit comprises:
a fourth switching tube, wherein the first end receives the power supply voltage, the control end is connected with the second end, and the second end outputs the second bias current;
a first end of the fifth switching tube receives the power supply voltage, a control end of the fifth switching tube is connected with a control end of the fourth switching tube, and a second end of the fifth switching tube outputs the third bias current;
and the first end of the sixth switching tube receives the power supply voltage, the control end of the sixth switching tube is connected with the second end of the sixth switching tube, and the second end of the sixth switching tube is also connected with the second end of the fifth switching tube.
Optionally, the comparing unit includes:
a third resistor;
a first end of the fourth resistor is connected with a second end of the third resistor, and the second end of the fourth resistor is grounded;
a seventh switch tube, a control end of which receives the detection voltage, a first end of which is connected with the bias unit to receive the second bias current, and a second end of which is connected with the first end of the third resistor;
and a control end of the eighth switching tube is connected with the control end of the seventh switching tube, a first end of the eighth switching tube is connected with the bias unit to receive the third bias current, and a second end of the eighth switching tube is connected with a first end of the fourth resistor.
Optionally, the sensitivity of the second bias current to voltage is less than the sensitivity of the third bias current to voltage.
Optionally, initial voltages of the control terminals of the seventh switching tube and the eighth switching tube are set to be reference voltages, the detection voltage is smaller than the reference voltages, the third bias current is smaller than the second bias current, and the comparison signal is in an active level state; the detection voltage is greater than the reference voltage, the third bias current is greater than the second bias current, and the comparison signal is in an invalid level state.
Optionally, the output unit includes:
and the control end of the ninth switching tube is connected with the first end of the eighth switching tube, the first end of the ninth switching tube receives the power supply voltage, and the second end of the ninth switching tube serves as the output end of the comparison module to output the comparison signal.
Optionally, the output of the comparison module further receives a load current.
Optionally, the output terminal of the voltage generation unit further receives a load current.
Optionally, the method further comprises:
and the filtering module is used for converting and shaping the waveform of the comparison signal so as to output an under-voltage protection signal.
Optionally, the filtering module includes:
the input end of the Schmitt trigger receives the comparison signal, and the output end of the Schmitt trigger outputs the undervoltage protection signal; and
and a filtering unit setting a filtering time based on the bias current and the capacitance.
Optionally, the voltage collecting unit further includes:
and the hysteresis window unit maintains or updates the voltage division coefficient of the voltage acquisition unit based on the undervoltage protection signal.
Optionally, when the under-voltage protection signal changes to an active level state, the voltage division coefficient remains unchanged; and under the condition that the undervoltage protection signal is changed into an invalid level state, the voltage division coefficient is updated.
Optionally, the hysteresis window unit includes:
a fifth resistor;
and the control end of the tenth switching tube receives the undervoltage protection signal, the first end of the tenth switching tube is connected with the first end of the fifth resistor and the voltage acquisition unit, and the second end of the tenth switching tube is connected with the second end of the fifth resistor and grounded.
According to the undervoltage protection circuit and the power module, only the voltage acquisition and power supply module in the undervoltage protection circuit is provided by the power supply voltage VCC, and a high-voltage tube is required to be arranged. The voltage acquisition and power supply module generates a power supply voltage which is used for supplying power inside the under-voltage protection circuit and is lower than the power supply voltage, and then the circuit module which is supplied power by the power supply voltage in the under-voltage protection circuit adopts a low-voltage tube to complete normal work. And then reduced the use quantity of high-voltage tube in the undervoltage protection circuit, effectively reduced work consumption current, and reduced the circuit area.
More closely, the voltage acquisition unit in the voltage acquisition and power supply module in the undervoltage protection circuit is not only used for gathering supply voltage output detection voltage, can also multiplex as bias circuit in order to provide first bias current to voltage generation unit, need not to set up the bias circuit of extra consumption current to circuit area has been reduced, undervoltage protection circuit's consumption has been reduced.
And the voltage acquisition unit in the voltage acquisition of under-voltage protection circuit and the power module in this application adopts the open-loop comparison circuit of band gap benchmark form to realize the benchmark comparison to detection voltage in the comparison module among the under-voltage protection circuit in this application, and need not to set up reference voltage production circuit and comparator alone to the temperature coefficient of under-voltage protection point and under-voltage recovery point is little, and the parameter uniformity is high.
Drawings
The above and other objects, features and advantages of the present invention will become more apparent from the following description of the embodiments of the present invention with reference to the accompanying drawings, in which:
FIG. 1 is a schematic diagram of an under-voltage protection circuit in the prior art;
fig. 2 is a schematic diagram illustrating a structure of an under-voltage protection circuit according to an embodiment of the present invention;
fig. 3 is a schematic circuit diagram illustrating a voltage acquisition and power supply module in an under-voltage protection circuit according to an embodiment of the present invention;
FIG. 4 is a schematic circuit diagram illustrating a reference comparison module in an under-voltage protection circuit according to an embodiment of the present invention;
fig. 5 is a circuit diagram of another under-voltage protection circuit according to an embodiment of the invention.
Detailed Description
Various embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Like elements in the various figures are denoted by the same or similar reference numerals. For purposes of clarity, the various features in the drawings are not necessarily drawn to scale.
The application provides an intelligent power module, its inside integrated drive circuit and protection circuit at least, drive circuit converts the required drive signal of rear end load into with the input signal who receives, and protection circuit exports all kinds of fault indication signals to drive circuit based on the testing result, carries out the protection action in order to protect drive circuit under the state that needs the protection, and then guarantees intelligent power module safety work. The protection circuit comprises an undervoltage protection circuit, an overcurrent protection circuit, a short-circuit protection circuit, an overheat protection circuit and the like. The application provides an under-voltage protection circuit that can be applied to among intelligent power module, is in the under-voltage protection signal of effective level state of output under the under-voltage state at mains voltage to control opens under-voltage protection and then closes back stage circuit (including drive circuit at least).
The undervoltage protection circuit and the power module provided by the present application will be described in detail with reference to the accompanying drawings.
Fig. 2 is a schematic structural diagram of an under-voltage protection circuit according to an embodiment of the present invention. Fig. 3 is a schematic circuit diagram of a voltage acquisition and power supply module in an under-voltage protection circuit according to an embodiment of the present invention. Fig. 4 is a schematic circuit diagram of a comparison module in an under-voltage protection circuit according to an embodiment of the present invention.
As shown in fig. 2, the under-voltage protection circuit 100 includes a voltage collecting and power supplying module 110 and a comparing module 12.
The voltage collecting and supplying module 110 is used for collecting a power voltage VCC and outputting a detection voltage Vsamp, and converting the power voltage VCC into a supply voltage VDD for internal power supply. The voltage collecting and supplying module 110 includes a voltage collecting unit 111 and a voltage generating unit 112. Referring to the circuit schematic diagram of the voltage collecting and power supplying module 110 in the under-voltage protection circuit 100 shown in fig. 3, as shown in fig. 3, the voltage collecting unit 111 divides the collected power voltage VCC to obtain the detection voltage Vsamp, and the voltage collecting unit 111 includes a first switching tube P1, a first resistor R1, and a second resistor R2. The first end of the first switch tube P1 receives the power supply voltage VCC, the control end of the first switch tube P1 is connected to the second end of the first switch tube P1, the second end of the first switch tube P1 is connected to the first end of the first resistor R1, the second end of the first resistor R1 is connected to the first end of the second resistor R2, and the second end of the second resistor R2 is grounded. The connection midpoint between the first resistor R1 and the second resistor R2 serves as the output terminal of the voltage collecting unit 111 for outputting the detection voltage Vsamp. The expression of the sense voltage Vsamp is:
. VGS1 is the gate-source voltage of the first switch tube P1. The voltage generating unit 112 generates a power supply voltage VDD for supplying power to other modules in the under-voltage protection circuit 100, and the voltage generating unit 112 includes a second switching tube P2, a diode D1, a third switching tube N1, and a first current source I1. The control terminal of the second switch transistor P2 is connected to the control terminal of the first switch transistor P1, and the first terminal of the second switch transistor P2 receives the power supply voltage VCC. The cathode of the diode D1 is grounded, and the anode of the diode D1 is connected to the second terminal of the second switch tube P2. A control terminal of the third switching tube N1 is connected with a cathode of a diode D1A first terminal of the switching tube N1 receives the power voltage VCC, a second terminal of the third switching tube N1 is grounded via the first current source I1, a second terminal of the third switching tube N1 outputs the power voltage VDD, and the first current source I1 provides the load current to an output terminal of the power voltage VDD. The voltage acquisition unit 111 is further multiplexed with the voltage generation unit 112 to provide the first bias current. Specifically, the first switch tube P1 and the second switch tube P2 form a first current mirror, the second terminal of the first switch tube P1 serves as the input terminal of the first current mirror to input the first bias current, and the second terminal of the second switch tube P2 serves as the output terminal of the first current mirror to output the mirror current of the first bias current. The diode D1 is, for example, a zener diode, and generates a stable intermediate voltage V0 by the mirror current. The expression for the supply voltage VDD is:
. VBE1 is the threshold voltage of the third switching transistor N1, and the intermediate voltage V0 is lower than the power supply voltage. And the supply voltage VDD is less than the supply voltage VCC. The first switching tube P1 and the second switching tube P2 are PMOS transistors, and the third switching tube N1 is an N-type triode. In other alternative embodiments, diode D1 may also be a shorted transistor. In other alternative embodiments, the third switch transistor N1 may also be an NMOS transistor.
The comparing module 120 is connected to the voltage collecting unit 111 of the voltage collecting and power supplying module 110 for receiving the detection voltage Vsamp, and connected to the voltage generating unit 112 of the voltage collecting and power supplying module 110 for receiving the power supply voltage VDD. The comparison module 120 normally operates based on the supply voltage VDD and is configured to perform a reference comparison on the detection voltage Vsamp to output a comparison signal OUT, which is used to control whether power is supplied to a load. Referring to fig. 4, a circuit diagram of the comparison module 120 in the undervoltage protection circuit 100 is shown, and as shown in fig. 4, the comparison module 120 includes a bias unit 121, a comparison unit 122, and an output unit 123. The bias unit 121 includes a fourth switching tube P3, a fifth switching tube P4, and a sixth switching tube P5. A first end of the fourth switching tube P3 is connected to the voltage generating unit 112 for receiving the supply voltage VDD, and a control end of the fourth switching tube P3 is connected to a second end of the fourth switching tube P3. The first end of the fifth switching tube P4 is connected to the voltage generating unit 112 for receiving the supply voltage VDD, and the control end of the fifth switching tube P4 is connected to the control end of the fourth switching tube P3. The first terminal of the sixth switching tube P5 is connected to the voltage generating unit 112 for receiving the supply voltage VDD, the control terminal of the sixth switching tube P5 is connected to the second terminal of the sixth switching tube P5, and the second terminal of the sixth switching tube P5 is connected to the second terminal of the fifth switching tube P4. The comparing unit 122 includes a seventh switch tube N2, an eighth switch tube N3, a third resistor R3, and a fourth resistor R4. A control end of the seventh switching tube N2 is connected to a control end of the eighth switching tube N3 and to an output end of the voltage collecting unit 111 in the voltage collecting and power supplying module 110 to receive the detection voltage Vsamp, a first end of the seventh switching tube N2 is connected to a second end of the fourth switching tube P3 in the bias unit 121, a second end of the seventh switching tube N2 is connected to a first end of the third resistor R3, and a second end of the third resistor R3 is connected to a first end of the fourth resistor R4. A first end of the eighth switch tube N3 is connected to the second end of the fifth switch tube P4 and the second end of the sixth switch tube P5 in the bias unit 121, respectively, a second end of the eighth switch tube N3 is connected to a first end of the fourth resistor R4, and a second end of the fourth resistor R4 is grounded. The output unit 123 includes a ninth switching tube P6, and more particularly, a second current source I2, for providing a load current to the output terminal of the comparing module 120. The control end of the ninth switching tube P6 is connected to the first end of the eighth switching tube N3, the first end of the ninth switching tube P6 is connected to the voltage generating unit 112 for receiving the supply voltage VDD, the second end of the ninth switching tube P6 serves as the output end of the comparing module 120 for outputting a comparison signal OUT, and the comparison signal OUT indicates to turn on or turn off the under-voltage protection for the subsequent circuit. The second terminal of the ninth switching tube P6 is also connected to ground via a second current source I2.
Further, the comparison unit 122 constitutes an open-loop comparison circuit in the form of a bandgap reference for reference-detecting the detection voltage Vsamp. The ratio of the emitting area of the seventh switch tube N2 to the emitting area of the eighth switch tube N3 is N: 1, in the preferred embodiment, N takes an appropriate value to achieve an optimal match. When the bias unit 121 provides the second bias current IA to the first terminal of the seventh switch tube N2 and provides the second bias current IA to the first terminal of the seventh switch tube N2When the second bias currents IB at the first end of the eighth switch tube N3 are equal, the voltages at the control end of the seventh switch tube N2 and the control end of the eighth switch tube N3 are equal
. Wherein the content of the first and second substances,
VBE2 represents the threshold voltage of the seventh switch tube N2, VBE3 represents the threshold voltage of the eighth switch tube N3, k is boltzmann's constant, q is the amount of electron charge, T is the temperature, and N is the ratio of the emitter areas of the seventh switch tube N2 and the eighth switch tube N3. The ratio of the emitter area between the seventh switch tube N2 and the eighth switch tube N3 and the ratio of the third resistor R3 and the fourth resistor R are set so that the voltage VC at the control terminal of the seventh switch tube N2 and the control terminal of the eighth switch tube N3 reaches a reference voltage, which is a threshold point of an open-loop comparator in the form of a bandgap reference. The seventh switch tube N2, the third resistor R3, and the fourth resistor R4 in the comparing unit 122 form a first cascode, and the eighth switch tube N3 and the fourth resistor R4 in the comparing unit 122 form a second cascode.
The bias unit 121 is configured to provide the second bias current IA and the third bias current IB to the comparison unit 122, so that the comparison unit 122 can implement a reference comparison function. The sensitivity of the second bias current IA provided to the first terminal of the seventh switch tube N2 and the third bias current IB provided to the first terminal of the eighth switch tube N3 in the bias unit 121 to the detection voltage Vsamp provided to the control terminal of the seventh switch tube N2 and the control terminal of the eighth switch tube N3 satisfy gmA < gmB, where gmA represents the sensitivity of the second bias current received by the output stage (the first terminal of the seventh switch tube N2) in the first cascode amplifier to the voltage, and gmB represents the sensitivity of the third bias current received by the output stage (the first terminal of the eighth switch tube N3) in the second cascode amplifier to the voltage. The sixth switching transistor P5 in the bias unit 121 is in a short diode connection manner, and is used for providing enough bias current to the eighth switching transistor N3 to prevent the eighth switching transistor N3 from entering a saturation region when the voltage at the first terminal of the eighth switching transistor N3 drops.
The output unit 123 outputs the comparison signal OUT in different level states based on the result of the reference comparison of the detection voltage Vsamp by the comparison unit 122. When the detection voltage Vsamp provided to the control terminal of the seventh switching tube N2 and the control terminal of the eighth switching tube N3 is smaller than the reference voltage, the second bias current at the first terminal of the seventh switching tube N2 is larger than the third bias current at the first terminal of the eighth switching tube N3, which causes the voltage at the first terminal of the eighth switching tube N3 to increase, and further controls the ninth switching tube P6 to turn off, the output terminal of the comparison module 120 outputs the comparison signal OUT in a low level state (active level state), and further controls the rear-stage circuit to enter an under-voltage protection state, and no power is supplied to the load. When the detection voltage Vsamp provided to the control terminal of the seventh switching tube N2 and the control terminal of the eighth switching tube N3 is greater than the reference voltage, the second bias current at the first terminal of the seventh switching tube N2 is smaller than the third bias current at the first terminal of the eighth switching tube N3, which causes the voltage at the first terminal of the eighth switching tube N3 to decrease, and further controls the ninth switching tube P6 to be turned on, and the output terminal of the comparison module 120 outputs the comparison signal OUT in a high level state (invalid level state), and further controls the rear-stage circuit not to enter an under-voltage protection state, and continues to supply power to the load. When the detection voltage Vsamp supplied to the control terminal of the seventh switching tube N2 and the control terminal of the eighth switching tube N3 is equal to the reference voltage, the second bias current at the first terminal of the seventh switching tube N2 is equal to the third bias current at the first terminal of the eighth switching tube N3, the voltage at the first terminal of the seventh switching tube N2 is equal to the voltage at the first terminal of the eighth switching tube N3, and the operating state of the ninth switching tube P6 remains conductive.
The fourth switching tube P3, the fifth switching tube P4, the sixth switching tube P5, and the ninth switching tube P6 are PMOS transistors, for example, and the seventh switching tube N2 and the eighth switching tube N3 are N-type triodes, for example.
More further, the under-voltage protection circuit 100 further includes a filtering module 130, which is powered by the supply voltage VDD and is configured to transform and shape a waveform of the comparison signal OUT indicating to turn on or turn off the under-voltage protection, so as to obtain the under-voltage protection signal UVLO. The filtering module 130 is connected to the voltage generating unit 112 of the voltage collecting and supplying module 110 to receive the supply voltage VDD, and is connected to the output end of the comparing module 120 to receive the comparison signal OUT and filter the comparison signal OUT to obtain the under-voltage protection signal UVLO. The supply voltage VDD is used to supply power to the filtering module 130 to maintain normal operation, and the under-voltage protection signal UVLO is obtained by performing waveform conversion and shaping on the comparison signal OUT, and is further used to control whether the post-stage circuit enters an under-voltage protection mode.
Fig. 5 is a circuit diagram of another under-voltage protection circuit according to an embodiment of the invention.
As shown in fig. 5, the under-voltage protection circuit 200 includes a voltage collecting and supplying module 210, a comparing module 220 and a filtering module 230. The voltage collecting and supplying module 210 includes a voltage collecting unit 211 and a voltage generating unit 212.
The voltage acquisition unit 211 is additionally provided with a hysteresis window unit 2111 and an eleventh switch tube N7 on the basis of the voltage acquisition unit 111. The hysteresis window unit 2111 includes a fifth resistor R5 and a tenth switching tube N4, and the fifth resistor R5 is connected between the second end of the second resistor R2 and ground. A first end of the tenth switching tube N4 is connected to the first end of the fifth resistor R5, a second end of the tenth switching tube N4 is connected to the second end of the fifth resistor R5, and a control end of the tenth switching tube N4 is connected to the output end of the filtering module 230. A control terminal of the eleventh switching tube N7 is connected to the output terminal of the voltage generating unit 212 to receive the supply voltage VDD, a first terminal of the eleventh switching tube N7 is connected to a first terminal of the second resistor R2, and a second terminal of the eleventh switching tube N7 serves as the output terminal of the voltage collecting unit 211 to output the detection voltage Vsamp. The eleventh switch tube N7 enables the obtained detection voltage Vsamp to follow the supply voltage VCC linearly, and provides the corresponding base current to the comparison module 220, where the base current is small, that is, the voltage dividing effect of the eleventh switch tube N7 on the supply voltage VCC is negligible. The hysteresis window unit 2111 maintains or updates the voltage division coefficient of the voltage acquisition unit 211 based on the under-voltage protection signal UVLO. That is, when the undervoltage protection signal UVLO changes to the active level state (jumps from the low level state to the high level state), the voltage division coefficient remains unchanged. The voltage division coefficient of the voltage acquisition unit 111 is used as the voltage division coefficient of the voltage acquisition unit 211, the tenth switching tube N4 is controlled to be switched on through an undervoltage protection signal UVLO, the fifth resistor R5 is in short circuit, and a branch composed of the first switching tube P1, the first resistor R1 and the second resistor R2 is used as an effective voltage acquisition branch in the voltage acquisition unit 211. When the undervoltage protection signal UVLO changes to the inactive level state (jumps from the high level state to the low level state), the voltage division coefficient is updated. The tenth switching tube N4 is controlled to be turned off by the undervoltage protection signal UVLO, and a branch composed of the first switching tube P1, the first resistor R1, the second resistor R2, and the fifth resistor R5 is used as an effective voltage acquisition branch in the voltage acquisition unit 211. The turning proportions of the two different voltage acquisition branches are different, so that a hysteresis difference value between an undervoltage protection point and an undervoltage recovery point is realized, and the oscillation phenomenon caused by repeated starting of the undervoltage protection circuit near the undervoltage protection point is prevented.
On the basis of the voltage generation unit 112, the bias circuit 2122 is used in the voltage generation unit 212 instead of the first current source I1. The bias circuit 2122 includes a twelfth switch transistor P7, a thirteenth switch transistor N5, and a fourteenth switch transistor N6. The control end of the twelfth switching tube P7 is connected to the control end of the first switching tube P1, the first end of the twelfth switching tube P7 receives the power voltage VCC, and the second end of the twelfth switching tube P7 is connected to the first end of the fourteenth switching tube N6. A first end of a thirteenth switching tube N5 is connected to the second end of the third switching tube N1, a second end of the thirteenth switching tube N5 is grounded, a control end of the thirteenth switching tube N5 is connected to a control end of the fourteenth switching tube N6, a control end of the fourteenth switching tube N6 is connected to a first end of the fourteenth switching tube N6, and a second end of the fourteenth switching tube N6 is grounded. The twelfth switching tube P7, the first switching tube P1, and the second switching tube P2 form a current mirror, the thirteenth switching tube N5, and the fourteenth switching tube N6 form a current mirror, and the first end of the thirteenth switching tube N5 provides a bias current to the supply voltage VDD. In alternative embodiments, the bias circuit 2122 used in place of the first current source I1 may alternatively be implemented using a bias resistor.
The comparison module 220 is based on the comparison module 120, and the second current source I2 is replaced by the bias circuit 2122 in the voltage collecting and power supplying module 110, and the bias circuit 2122 provides a current to the output terminal of the comparison module 220 via the filtering module 230.
The filtering module 230 includes a schmitt trigger U1 and a filtering unit 231. An input terminal of the schmitt trigger U1 is connected to the output terminal of the comparison module 120 to receive the comparison signal OUT, and an output terminal of the schmitt trigger U1 outputs the undervoltage protection signal UVLO. The filtering unit 231 includes a fifteenth switching tube N8 and a capacitor C1, a control end of the fifteenth switching tube N8 is connected to a control end of a fourteenth switching tube N6 of the bias circuit 2122 of the voltage collecting and supplying module 210, a first end of the fifteenth switching tube N8 is connected to one end of the capacitor C1 and to the output end of the comparing module 220, and a second end of the fifteenth switching tube N8 is connected to the other end of the capacitor C1 and to ground. The thirteenth switching tube N5, the fourteenth switching tube N6, and the fifteenth switching tube N8 form a current mirror, and are used for providing a load current to the output terminal of the comparison module 220. The network formed by the capacitor C1 in the filtering unit 231 and the current flowing in through the fifteenth switch tube N8 can set the filtering time required by the system. The schmitt trigger U1 is used to transform and shape the waveform of the comparison signal OUT, and the obtained undervoltage protection signal UVLO is the inverted and shaped signal waveform of the comparison signal OUT.
In the voltage acquisition unit 211 in the voltage acquisition and power supply module 210 in the under-voltage protection circuit 200 provided in this embodiment, the hysteresis window unit 2111 is added on the basis of the voltage acquisition unit 111, so that a hysteresis difference between an under-voltage protection point and an under-voltage recovery point can be realized. Wherein, the voltage value of the undervoltage protection point
Voltage value of undervoltage recovery point
. Thereby obtaining the hysteresis voltage
。
The undervoltage protection circuit and the power module provided by the above embodiments only have the voltage acquisition and power supply module provided by the power supply voltage VCC, and need to be provided with a high voltage tube. And the other modules are supplied with power by the power supply voltage VDD output by the voltage generation unit in the voltage acquisition and power supply module, and the power supply voltage VDD is lower than the power supply voltage VCC, so that the normal work can be completed by adopting a low-voltage tube. To sum up, the undervoltage protection circuit provided by the application reduces the use number of high-voltage tubes, effectively reduces the work consumption current and reduces the circuit area. And voltage acquisition unit among the voltage acquisition of under-voltage protection circuit and the power module in this application not only is used for gathering mains voltage output detection voltage, can also multiplex as the bias unit in order to provide bias current to voltage generation unit, does not have the bias circuit of extra consumption current to reduce circuit area, reduced under-voltage protection circuit's consumption. In addition, in a comparison module in the undervoltage protection circuit, the open-loop comparison circuit in a band-gap reference form is adopted to realize reference comparison of the detection voltage, a reference voltage generation circuit and a comparator do not need to be independently arranged, the temperature coefficients of an undervoltage protection point and an undervoltage recovery point are small, and the parameter consistency is high.
While embodiments in accordance with the invention have been described above, these embodiments are not intended to be exhaustive or to limit the invention to the precise embodiments described. Obviously, many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and the practical application, to thereby enable others skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated. The invention is limited only by the claims and their full scope and equivalents.
Claims (34)
1. An undervoltage protection circuit, comprising:
the voltage sampling and power supply module comprises a voltage acquisition unit and a voltage generation unit, wherein the voltage acquisition unit acquires power supply voltage and outputs detection voltage, and the voltage acquisition unit is multiplexed to provide first bias current; the voltage generation unit is connected with the voltage acquisition unit to receive the first bias current and convert the power supply voltage into a power supply voltage for internal power supply, wherein the power supply voltage is smaller than the power supply voltage;
the comparison module is connected with the voltage sampling and power supply module, compares the detected voltage with a reference and outputs a comparison signal, the comparison signal is used for controlling whether to supply power to a load or not,
wherein the supply voltage supplies power to the comparison module.
2. The undervoltage protection circuit of claim 1, wherein the comparison module comprises:
the comparison unit is an open-loop comparison circuit in a band gap reference form and is used for performing reference comparison on the detection voltage;
the bias unit receives the supply voltage and is connected with the comparison unit to provide a second bias current and a third bias current; and
and the output unit is connected with the comparison unit and outputs the comparison signal based on a reference comparison result.
3. The undervoltage protection circuit of claim 1, wherein the voltage acquisition unit comprises:
a first switch tube, a first end receiving the power voltage, a second end connected with a control end to provide the first bias current;
the first end of the first resistor is connected with the second end of the first switching tube, and the second end of the first resistor is used as the output end of the voltage acquisition unit to output the detection voltage; and
and the first end of the second resistor is connected with the second end of the first resistor, and the second end of the second resistor is grounded.
4. The undervoltage protection circuit of claim 3, wherein the voltage generation unit comprises:
a control end of the second switching tube is connected with a control end of the first switching tube, a first end of the second switching tube receives the power supply voltage, and a second end of the second switching tube provides the first bias current;
the anode of the diode is connected with the second end of the second switching tube, and the cathode of the diode is grounded; and the control end of the third switching tube is connected with the anode of the diode, the first end of the third switching tube is connected with the first end of the second switching tube, and the second end of the third switching tube is used as the output end of the voltage generation unit to output the power supply voltage.
5. The undervoltage protection circuit of claim 4, wherein the diode is a Zener diode or a transistor shorted as a diode, the first and second switching tubes are P-type transistors, and the third switching tube is an N-type transistor.
6. The undervoltage protection circuit of claim 2, wherein the biasing unit comprises:
a fourth switching tube, wherein the first end receives the power supply voltage, the control end is connected with the second end, and the second end outputs the second bias current;
a first end of the fifth switching tube receives the power supply voltage, a control end of the fifth switching tube is connected with a control end of the fourth switching tube, and a second end of the fifth switching tube outputs the third bias current;
and the first end of the sixth switching tube receives the power supply voltage, the control end of the sixth switching tube is connected with the second end of the sixth switching tube, and the second end of the sixth switching tube is also connected with the second end of the fifth switching tube.
7. The undervoltage protection circuit of claim 2, wherein the comparison unit comprises:
a third resistor;
a first end of the fourth resistor is connected with a second end of the third resistor, and the second end of the fourth resistor is grounded;
a seventh switch tube, a control end of which receives the detection voltage, a first end of which is connected with the bias unit to receive the second bias current, and a second end of which is connected with the first end of the third resistor;
and a control end of the eighth switching tube is connected with the control end of the seventh switching tube, a first end of the eighth switching tube is connected with the bias unit to receive the third bias current, and a second end of the eighth switching tube is connected with a first end of the fourth resistor.
8. The undervoltage protection circuit of claim 7, wherein a sensitivity of the second bias current to voltage is less than a sensitivity of the third bias current to voltage.
9. The undervoltage protection circuit of claim 7, wherein initial voltages of the control terminals of the seventh switching tube and the eighth switching tube are set to a reference voltage, the detection voltage is smaller than the reference voltage, the third bias current is smaller than the second bias current, and the comparison signal is in an active level state; the detection voltage is greater than the reference voltage, the third bias current is greater than the second bias current, and the comparison signal is in an invalid level state.
10. The undervoltage protection circuit of claim 9, wherein the output unit comprises:
and the control end of the ninth switching tube is connected with the first end of the eighth switching tube, the first end of the ninth switching tube receives the power supply voltage, and the second end of the ninth switching tube serves as the output end of the comparison module to output the comparison signal.
11. The undervoltage protection circuit of claim 9, wherein the output of the comparison module further receives a load current.
12. The undervoltage protection circuit of claim 4, wherein the output of the voltage generation unit further receives a load current.
13. The undervoltage protection circuit of claim 1, further comprising:
and the filtering module is powered by the power supply voltage and is used for converting and shaping the waveform of the comparison signal to output an undervoltage protection signal.
14. The undervoltage protection circuit of claim 13, wherein the filtering module comprises:
the input end of the Schmitt trigger receives the comparison signal, and the output end of the Schmitt trigger outputs the undervoltage protection signal; and
and a filtering unit setting a filtering time based on the bias current and the capacitance.
15. The undervoltage protection circuit of claim 14, wherein the voltage acquisition unit further comprises:
and the hysteresis window unit maintains or updates the voltage division coefficient of the voltage acquisition unit based on the undervoltage protection signal.
16. The undervoltage protection circuit of claim 15, wherein the voltage division coefficient remains unchanged when the undervoltage protection signal changes to an active level state; and under the condition that the undervoltage protection signal is changed into an invalid level state, the voltage division coefficient is updated.
17. The undervoltage protection circuit of claim 16, wherein the hysteresis window unit comprises:
a fifth resistor;
and the control end of the tenth switching tube receives the undervoltage protection signal, the first end of the tenth switching tube is connected with the first end of the fifth resistor and the voltage acquisition unit, and the second end of the tenth switching tube is connected with the second end of the fifth resistor and grounded.
18. A power module comprising an undervoltage protection circuit, the undervoltage protection circuit comprising:
the voltage sampling and power supply module comprises a voltage acquisition unit and a voltage generation unit, wherein the voltage acquisition unit acquires power supply voltage and outputs detection voltage, and the voltage acquisition unit is multiplexed to provide first bias current; the voltage generation unit is connected with the voltage acquisition unit to receive the first bias current and convert the power supply voltage into a power supply voltage for internal power supply, wherein the power supply voltage is smaller than the power supply voltage;
the comparison module is connected with the voltage sampling and power supply module, compares the detected voltage with a reference and outputs a comparison signal, the comparison signal is used for controlling whether to supply power to a load or not,
wherein the supply voltage supplies power to the comparison module.
19. The power module of claim 18 wherein the comparison module comprises:
the comparison unit is an open-loop comparison circuit in a band gap reference form and is used for performing reference comparison on the detection voltage;
the bias unit receives the supply voltage and is connected with the comparison unit to provide a second bias current and a third bias current; and
and the output unit is connected with the comparison unit and outputs the comparison signal based on a reference comparison result.
20. The power module of claim 18 wherein the voltage acquisition unit comprises:
a first switch tube, a first end receiving the power voltage, a second end connected with a control end to provide the first bias current;
the first end of the first resistor is connected with the second end of the first switching tube, and the second end of the first resistor is used as the output end of the voltage acquisition unit to output the detection voltage; and
and the first end of the second resistor is connected with the second end of the first resistor, and the second end of the second resistor is grounded.
21. The power module of claim 20, wherein the voltage generation unit comprises:
a control end of the second switching tube is connected with a control end of the first switching tube, a first end of the second switching tube receives the power supply voltage, and a second end of the second switching tube provides the first bias current;
the anode of the diode is connected with the second end of the second switching tube, and the cathode of the diode is grounded;
and the control end of the third switching tube is connected with the anode of the diode, the first end of the third switching tube is connected with the first end of the second switching tube, and the second end of the third switching tube is used as the output end of the voltage generation unit to output the power supply voltage.
22. The power module of claim 21, wherein the diode is a zener diode or a transistor shorted as a diode, the first and second switching tubes are P-type transistors, and the third switching tube is an N-type transistor.
23. The power module of claim 19, wherein the biasing unit comprises:
a fourth switching tube, wherein the first end receives the power supply voltage, the control end is connected with the second end, and the second end outputs the second bias current;
a first end of the fifth switching tube receives the power supply voltage, a control end of the fifth switching tube is connected with a control end of the fourth switching tube, and a second end of the fifth switching tube outputs the third bias current;
and the first end of the sixth switching tube receives the power supply voltage, the control end of the sixth switching tube is connected with the second end of the sixth switching tube, and the second end of the sixth switching tube is also connected with the second end of the fifth switching tube.
24. The power module of claim 19, wherein the comparison unit comprises:
a third resistor;
a first end of the fourth resistor is connected with a second end of the third resistor, and the second end of the fourth resistor is grounded;
a seventh switch tube, a control end of which receives the detection voltage, a first end of which is connected with the bias unit to receive the second bias current, and a second end of which is connected with the first end of the third resistor;
and a control end of the eighth switching tube is connected with the control end of the seventh switching tube, a first end of the eighth switching tube is connected with the bias unit to receive the third bias current, and a second end of the eighth switching tube is connected with a first end of the fourth resistor.
25. The power module of claim 24 wherein the second bias current is less sensitive to voltage than the third bias current.
26. The power module of claim 24, wherein initial voltages of the control terminals of the seventh switching tube and the eighth switching tube are set to a reference voltage, the detection voltage is smaller than the reference voltage, the third bias current is smaller than the second bias current, and the comparison signal is in an active level state; the detection voltage is greater than the reference voltage, the third bias current is greater than the second bias current, and the comparison signal is in an invalid level state.
27. The power module of claim 26, wherein the output unit comprises:
and the control end of the ninth switching tube is connected with the first end of the eighth switching tube, the first end of the ninth switching tube receives the power supply voltage, and the second end of the ninth switching tube serves as the output end of the comparison module to output the comparison signal.
28. The power module of claim 26 wherein the output of the comparison module further receives a load current.
29. The power module of claim 21 wherein the output of the voltage generation unit further receives a load current.
30. The power module of claim 18, further comprising:
and the filtering module is used for converting and shaping the waveform of the comparison signal so as to output an under-voltage protection signal.
31. The power module of claim 30 wherein the filtering module comprises:
the input end of the Schmitt trigger receives the comparison signal, and the output end of the Schmitt trigger outputs the undervoltage protection signal; and
and a filtering unit setting a filtering time based on the bias current and the capacitance.
32. The power module of claim 31 wherein the voltage acquisition unit further comprises:
and the hysteresis window unit maintains or updates the voltage division coefficient of the voltage acquisition unit based on the undervoltage protection signal.
33. The power module of claim 32, wherein the voltage divider coefficient remains unchanged when the under-voltage protection signal changes to an active level state; and under the condition that the undervoltage protection signal is changed into an invalid level state, the voltage division coefficient is updated.
34. The power module of claim 33, wherein the hysteresis window unit comprises:
a fifth resistor;
and the control end of the tenth switching tube receives the undervoltage protection signal, the first end of the tenth switching tube is connected with the first end of the fifth resistor and the voltage acquisition unit, and the second end of the tenth switching tube is connected with the second end of the fifth resistor and grounded.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111330791.0A CN113783160B (en) | 2021-11-11 | 2021-11-11 | Undervoltage protection circuit and power module |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111330791.0A CN113783160B (en) | 2021-11-11 | 2021-11-11 | Undervoltage protection circuit and power module |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113783160A CN113783160A (en) | 2021-12-10 |
| CN113783160B true CN113783160B (en) | 2022-04-01 |
Family
ID=78873801
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111330791.0A Active CN113783160B (en) | 2021-11-11 | 2021-11-11 | Undervoltage protection circuit and power module |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113783160B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115377939B (en) * | 2022-07-18 | 2023-05-23 | 北京炎黄国芯科技有限公司 | Adjustable undervoltage protection circuit and electronic equipment |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101237182A (en) * | 2008-02-19 | 2008-08-06 | 北京中星微电子有限公司 | A method for forming the standard voltage of under-voltage lock circuit and its circuit |
| CN104113041B (en) * | 2014-05-30 | 2017-03-29 | 西安电子科技大学 | A kind of under-voltage protecting circuit for POE |
| CN104122925B (en) * | 2014-07-18 | 2015-08-05 | 上海凌阳科技有限公司 | A kind of internal electrical source generating circuit being applied to Power Management Unit |
| CN107102673B (en) * | 2017-06-22 | 2018-07-20 | 中国电子科技集团公司第五十八研究所 | Undervoltage lockout circuit with lag function |
-
2021
- 2021-11-11 CN CN202111330791.0A patent/CN113783160B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN113783160A (en) | 2021-12-10 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN113783160B (en) | Undervoltage protection circuit and power module | |
| CN112769093A (en) | Current-limiting control circuit, chip and power supply | |
| CN208353213U (en) | A kind of Switching Power Supply start-up circuit | |
| CN209805402U (en) | USB overvoltage protection circuit with temperature compensation function | |
| CN114489216B (en) | Protection circuit applied to LDO (low dropout regulator) | |
| CN217115613U (en) | Undervoltage protection circuit | |
| CN211830191U (en) | Under-voltage locking circuit | |
| CN101197565A (en) | Solid relay with overflow protection | |
| CN117471152B (en) | Low-power-consumption voltage detection circuit | |
| CN117492509B (en) | Low-voltage comparison circuit | |
| CN1734269A (en) | low-voltage detection circuit | |
| CN117713506B (en) | Low-power consumption power supply with wide output voltage range | |
| CN109842093A (en) | A kind of undervoltage lockout circuit and switching power source chip | |
| CN109687387B (en) | Overcurrent protection circuit | |
| CN213814437U (en) | Double-feedback constant current circuit based on linear voltage stabilization | |
| CN218162212U (en) | Switch power supply energy protection circuit | |
| CN220511295U (en) | Current-limiting protection circuit and emergency lighting equipment thereof | |
| CN219247462U (en) | Input voltage protection circuit supporting soft start and radio frequency switch device | |
| CN220961664U (en) | Voltage sampling circuit and new energy automobile | |
| CN212992009U (en) | Discrete adjustable voltage stabilizer and wireless charging device using same | |
| CN219247466U (en) | Hardware circuit suitable for overvoltage and undervoltage self-protection function of switching power supply | |
| CN218733218U (en) | Input protection circuit of switching power supply | |
| CN219394411U (en) | Overcurrent dynamic protection circuit of optical device | |
| CN220933054U (en) | Open-loop Hall current sensor power supply stabilizing circuit | |
| CN212622792U (en) | Overvoltage detection circuit, overcurrent detection circuit and protection detection circuit |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |