CN201349125Y - Short-circuit protection circuit for voltage stabilizer - Google Patents
Short-circuit protection circuit for voltage stabilizer Download PDFInfo
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- CN201349125Y CN201349125Y CNU200820145147XU CN200820145147U CN201349125Y CN 201349125 Y CN201349125 Y CN 201349125Y CN U200820145147X U CNU200820145147X U CN U200820145147XU CN 200820145147 U CN200820145147 U CN 200820145147U CN 201349125 Y CN201349125 Y CN 201349125Y
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Abstract
The utility model relates to a short-circuit protection circuit for a voltage stabilizer, which comprises an electric current output tube, a magnifier, a feedback resistor R1 and a feedback resistor R2, and is characterized in that the short-circuit protection circuit is formed by an output current sampling circuit, a reference current sampling circuit, an electric current sensing circuit and a short-circuit current shutdown circuit. The utility model has the advantages that: 1. the structure of an electric current mirror image is adopted, and a resistor is not used; the area is reduced, and the output current and the input current are output by a certain proportional relation, thereby enhancing the electric current precision of the short-circuit protection circuit; 2. the short-circuit protection circuit is not influenced by the technological angle of the tube and the resistance deflection, so the precision is enhanced; 3. the mode of the magnifier is adopted to increase response speed; 4. the circuit structure is simple, and is easy to realize with high reliability; 5. the short-circuit protection circuit is suitably applied to various kinds of circuit systems which need overcurrent or short-circuit protection.
Description
(1) technical field:
The utility model relates to a kind of circuit overcurrent protection, especially a kind of pressurizer short-circuit protection circuit.
(2) background technology:
At present power-supplying circuit; for example among switching regulator DCDC, the low-voltage-drop linear voltage regulator LDO; because it will provide bigger electric current; so excessive at output current, particularly under the situation of output short-circuit, the direct ground connection of output; super-high-current flows through the electric current efferent duct; cause circuit to damage,, circuit is protected so in foregoing circuit, should increase the pressurizer short-circuit protection circuit of detection of excessive current phenomenon.
Fig. 1 has provided the block diagram of the LDO that has increased short-circuit protection circuit, and the inverting input of amplifier connects reference voltage, resistance R
1And R
2Be connected and connect the positive input terminal of amplifier simultaneously; Accompanying drawing 2 has provided the block diagram of existing short-circuit protection circuit, wherein resistance R
3One end and current sampling circuit and metal-oxide-semiconductor M
sThe grid end be connected metal-oxide-semiconductor M
0Drain terminal be connected with the short circuit current breaking circuit, the source end is connected with ground, resistance R
1And R
2Be connected and connect the positive input terminal of amplifier simultaneously; Common short circuit current protective circuit utilizes the output current sample circuit to gather the electric current of electric current efferent duct, flows through resistance R then
3, control metal-oxide-semiconductor M
0When output current was bigger, the electric current of output current sample circuit was also bigger, resistance R
3On voltage ratio bigger, open metal-oxide-semiconductor M
0, the output overcurrent signal removes the cut-off current efferent duct to the short circuit current breaking circuit thereby make it export control signal; This scheme has adopted resistance, and area is bigger, in addition owing to be to utilize ohmically voltage to remove to open metal-oxide-semiconductor M
0So the deviation of the deviation of resistance, the technology of metal-oxide-semiconductor all can have influence on the precision of whole short circuit current protection, so the ratio of precision of short circuit current protection is relatively poor.
(3) utility model content:
The purpose of this utility model is to provide a kind of pressurizer short-circuit protection circuit, and it is a kind of simple in structure, precision height, the pressurizer short-circuit protection circuit that response speed is fast.
The technical solution of the utility model: a kind of pressurizer short-circuit protection circuit, comprise electric current efferent duct, amplifier, feedback resistance R1 and feedback resistance R2, it is characterized in that it is made up of output current sample circuit, reference current sample circuit, current detection circuit and short circuit current breaking circuit; Wherein, said electric current efferent duct with amplifier power end be connected with power supply respectively; An input of said amplifier receives reference voltage signal, and another input then is connected with ground by feedback resistance R2, and the 3rd input then receives the control signal by the output of short circuit current breaking circuit; The output of said amplifier is connected with the input of electric current efferent duct; The input of said electric current efferent duct current sampling circuit receives the current signal by the output output of electric current efferent duct, and exports it to current detection circuit; The input of said reference current sample circuit receives the reference current signal, and exports this current signal to current detection circuit; The output output overcurrent signal of said current detection circuit is to the short circuit current breaking circuit; The earth terminal of said electric current efferent duct is by feedback resistance R1 and feedback resistance R2 ground connection, its output output voltage signal.
Above-mentioned said electric current efferent duct is made of transistor MPT, said electric current efferent duct current sampling circuit is made of transistor M0, said reference current sample circuit is made of transistor M1 and transistor M4, said current detection circuit is made of pipe transistor M0, transistor M1 and transistor M2, and said short circuit current breaking circuit is made of transistor M3; The source electrode of wherein said transistor M0 and MPT is connected with power supply; The grid of said transistor M0 and transistor MPT is connected, and the drain electrode of said transistor MPT is by feedback resistance R1 and feedback resistance R2 ground connection; The drain electrode of said transistor M0 is connected with drain electrode with the drain electrode of transistor M1, the grid of transistor M3 and the grid of transistor M2; The grid of said transistor M1 is connected with the grid of M4, drain electrode; The source ground of said transistor M1, transistor M2, transistor M3 and transistor M4, feedback resistance R1 are connected with feedback resistance R2 simultaneously as the resistance feedback input end.
A kind of application of pressurizer short-circuit protection circuit is characterized in that it is applied in overcurrent or the short-circuit protection circuit system.
Operation principle of the present utility model:
The electric current of electric current efferent duct current sampling circuit image current efferent duct compares by this electric current and reference current, produces the short circuit current control signal; Reference current sample circuit mirror image reference current, and and the image current of electric current efferent duct relatively; Current detection circuit is used for detecting the relation between the image current that the electric current efferent duct gets image current and reference current; The short circuit current breaking circuit then turn-offs the output current pipe by the signal of current detection module, the protection entire circuit.
If set electric current I
0For electric current efferent duct current sampling circuit is gathered electric current, electric current I
1Be reference current sample circuit sample rate current, its current value and reference current I
RefValue equates, electric current I
2Be electric current I
0And I
1Poor; When output current was smaller, current mirror image tube output current was also smaller, i.e. I as shown in Figure 4
0＜I
Ref, electric current I then
2=0, the pressurizer short-circuit protection circuit is inoperative; When output current is bigger, surpass the short circuit current protection value, then this moment I
2=I
0-I
Ref, short circuit current breaking circuit M
3The output short circuit current cut-off signals, the cut-off current efferent duct is protected circuit.
Superiority of the present utility model is: 1, adopt the structure of current mirror, do not use resistance, reduced area, output current and input current have improved the current precision of short-circuit protection circuit according to certain proportionate relationship output; 2, be not subjected to the influence of pipe process corner, be not subjected to the influence of resistance deviation, so improved precision; 3, adopt the mode of amplifier, make response speed fast; 4, circuit structure is simple, be easy to realize, and the reliability height; 5, be fit to be applied in various needs overcurrent or the short-circuit protection circuit system.
(4) description of drawings:
Fig. 1 is for having increased the circuit block diagram of the low-voltage-drop linear voltage regulator LDO of short-circuit protection circuit in the prior art.
Fig. 2 is the block diagram of short-circuit protection circuit of the prior art.
Fig. 3 is the structured flowchart of the related a kind of pressurizer short-circuit protection circuit of the utility model.
Fig. 4 is the circuit structure diagram of the related a kind of pressurizer short-circuit protection circuit of the utility model.
Wherein, resistance R 1 and R2 are feedback resistance, and R3 is the short circuit current sampling resistor, and MS is the short circuit current protection control switch; MPT is the electric current efferent duct, and M0 is that current mirror output is managed mutually, and M1 is that the reference current mirror image is managed mutually with M4; M2 is the current detecting pipe, and M3 is that short circuit current turn-offs pipe, electric current I
0For electric current efferent duct current sampling circuit is gathered electric current, electric current I
1Be reference current sample circuit sample rate current, I
RefBe reference current, I
2Be electric current I
0And electric current I
1Poor.
(5) embodiment:
Embodiment: a kind of pressurizer short-circuit protection circuit (see figure 3), comprise electric current efferent duct, amplifier, feedback resistance R1 and feedback resistance R2, it is characterized in that it is made up of output current sample circuit, reference current sample circuit, current detection circuit and short circuit current breaking circuit; Wherein, said electric current efferent duct with amplifier power end be connected with power supply respectively; An input of said amplifier receives reference voltage signal, and another input then is connected with ground by feedback resistance R2, and the 3rd input then receives the control signal by the output of short circuit current breaking circuit; The output of said amplifier is connected with the input of electric current efferent duct; The input of said electric current efferent duct current sampling circuit receives the current signal by the output output of electric current efferent duct, and exports it to current detection circuit; The input of said reference current sample circuit receives the reference current signal, and exports this current signal to current detection circuit; The output output overcurrent signal of said current detection circuit is to the short circuit current breaking circuit; The earth terminal of said electric current efferent duct is by feedback resistance R1 and feedback resistance R2 ground connection, its output output voltage signal.
Above-mentioned said electric current efferent duct is made of transistor MPT, said electric current efferent duct current sampling circuit is made of transistor M0, said reference current sample circuit is made of transistor M1 and transistor M4, said current detection circuit is made of pipe transistor M0, transistor M1 and transistor M2, and said short circuit current breaking circuit is made of transistor M3; The source electrode of wherein said transistor M0 and MPT is connected with power supply; The grid of said transistor M0 and transistor MPT is connected, and the drain electrode of said transistor MPT is by feedback resistance R1 and feedback resistance R2 ground connection; The drain electrode of said transistor M0 is connected with drain electrode with the drain electrode of transistor M1, the grid of transistor M3 and the grid of transistor M2; The grid of said transistor M1 is connected with the grid of M4, drain electrode; The source ground of said transistor M1, transistor M2, transistor M3 and transistor M4, feedback resistance R1 are connected with feedback resistance R2 simultaneously as the resistance feedback input end.(see figure 4)
A kind of application of pressurizer short-circuit protection circuit is characterized in that it is applied in overcurrent or the short-circuit protection circuit system.
Claims (2)
1, a kind of pressurizer short-circuit protection circuit, comprise electric current efferent duct, amplifier, feedback resistance R1 and feedback resistance R2, it is characterized in that it is made up of output current sample circuit, reference current sample circuit, current detection circuit and short circuit current breaking circuit; Wherein, said electric current efferent duct with amplifier power end be connected with power supply respectively; An input of said amplifier receives reference voltage signal, and another input then is connected with ground by feedback resistance R2, and the 3rd input then receives the control signal by the output of short circuit current breaking circuit; The output of said amplifier is connected with the input of electric current efferent duct; The input of said electric current efferent duct current sampling circuit receives the current signal by the output output of electric current efferent duct, and exports it to current detection circuit; The input of said reference current sample circuit receives the reference current signal, and exports this current signal to current detection circuit; The output output overcurrent signal of said current detection circuit is to the short circuit current breaking circuit; The earth terminal of said electric current efferent duct is by feedback resistance R1 and feedback resistance R2 ground connection, its output output voltage signal.
2, according to the said a kind of pressurizer short-circuit protection circuit of claim 1, it is characterized in that said electric current efferent duct is made of transistor MPT, said electric current efferent duct current sampling circuit is made of transistor M0, said reference current sample circuit is made of transistor M1 and transistor M4, said current detection circuit is made of pipe transistor M0, transistor M1 and transistor M2, and said short circuit current breaking circuit is made of transistor M3; The source electrode of wherein said transistor M0 and MPT is connected with power supply; The grid of said transistor M0 and transistor MPT is connected, and the drain electrode of said transistor MPT is by feedback resistance R1 and feedback resistance R2 ground connection; The drain electrode of said transistor M0 is connected with drain electrode with the drain electrode of transistor M1, the grid of transistor M3 and the grid of transistor M2; The grid of said transistor M1 is connected with the grid of M4, drain electrode; The source ground of said transistor M1, transistor M2, transistor M3 and transistor M4, feedback resistance R1 are connected with feedback resistance R2 simultaneously as the resistance feedback input end.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU200820145147XU CN201349125Y (en) | 2008-12-30 | 2008-12-30 | Short-circuit protection circuit for voltage stabilizer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU200820145147XU CN201349125Y (en) | 2008-12-30 | 2008-12-30 | Short-circuit protection circuit for voltage stabilizer |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN201349125Y true CN201349125Y (en) | 2009-11-18 |
Family
ID=41368591
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNU200820145147XU Expired - Fee Related CN201349125Y (en) | 2008-12-30 | 2008-12-30 | Short-circuit protection circuit for voltage stabilizer |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN201349125Y (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101562323B (en) * | 2008-12-30 | 2012-04-18 | 天津南大强芯半导体芯片设计有限公司 | Short-circuit protection circuit |
| TWI398747B (en) * | 2010-07-16 | 2013-06-11 | Richpower Microelectronics | Power stage control circuit |
| CN103887761A (en) * | 2014-03-20 | 2014-06-25 | 深圳创维－Rgb电子有限公司 | PWM driving circuit |
| TWI575351B (en) * | 2016-03-08 | 2017-03-21 | 瑞昱半導體股份有限公司 | Regulator |
| CN113495592A (en) * | 2020-04-07 | 2021-10-12 | 炬芯科技股份有限公司 | Short-circuit current protection device and method for LDO (low dropout regulator), and LDO |
| CN116505893A (en) * | 2023-06-28 | 2023-07-28 | 深圳前海深蕾半导体有限公司 | AB type earphone driver |
| CN117707280A (en) * | 2024-02-05 | 2024-03-15 | 江苏润石科技有限公司 | Output stage control circuit with short-circuit current feedback limitation and application thereof |
-
2008
- 2008-12-30 CN CNU200820145147XU patent/CN201349125Y/en not_active Expired - Fee Related
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101562323B (en) * | 2008-12-30 | 2012-04-18 | 天津南大强芯半导体芯片设计有限公司 | Short-circuit protection circuit |
| TWI398747B (en) * | 2010-07-16 | 2013-06-11 | Richpower Microelectronics | Power stage control circuit |
| CN103887761A (en) * | 2014-03-20 | 2014-06-25 | 深圳创维－Rgb电子有限公司 | PWM driving circuit |
| CN103887761B (en) * | 2014-03-20 | 2017-08-08 | 深圳创维－Rgb电子有限公司 | PWM drive circuit |
| TWI575351B (en) * | 2016-03-08 | 2017-03-21 | 瑞昱半導體股份有限公司 | Regulator |
| CN113495592A (en) * | 2020-04-07 | 2021-10-12 | 炬芯科技股份有限公司 | Short-circuit current protection device and method for LDO (low dropout regulator), and LDO |
| CN116505893A (en) * | 2023-06-28 | 2023-07-28 | 深圳前海深蕾半导体有限公司 | AB type earphone driver |
| CN116505893B (en) * | 2023-06-28 | 2023-09-26 | 深圳前海深蕾半导体有限公司 | AB type earphone driver |
| CN117707280A (en) * | 2024-02-05 | 2024-03-15 | 江苏润石科技有限公司 | Output stage control circuit with short-circuit current feedback limitation and application thereof |
| CN117707280B (en) * | 2024-02-05 | 2024-04-23 | 江苏润石科技有限公司 | Output stage control circuit with short-circuit current feedback limitation and application thereof |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20091118 Termination date: 20131230 |