CN201639273U - Switching power supply short-circuit protective circuit - Google Patents
Switching power supply short-circuit protective circuit Download PDFInfo
- Publication number
- CN201639273U CN201639273U CN2010201015868U CN201020101586U CN201639273U CN 201639273 U CN201639273 U CN 201639273U CN 2010201015868 U CN2010201015868 U CN 2010201015868U CN 201020101586 U CN201020101586 U CN 201020101586U CN 201639273 U CN201639273 U CN 201639273U
- Authority
- CN
- China
- Prior art keywords
- circuit
- short
- power supply
- output
- switching power
- 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.)
- Expired - Fee Related
Links
Images
Landscapes
- Dc-Dc Converters (AREA)
Abstract
The utility model discloses a switching power supply short-circuit protective circuit, comprising a PWM control circuit, a short-circuit monitoring impulse circuit, a RC integrating circuit, a DC / DC converter closing control circuit and an output short-circuit monitoring circuit, all of which are connected sequentially; the output short-circuit monitoring circuit is connected to the output terminal of the power supply. The switching power supply of the utility model has the advantages of security and stability.
Description
Technical field
The utility model relates to field of power supplies, relates in particular to a kind of protective circuit of switch power source with short-circuit protection.
Background technology
Development with switch power technology; the technology of various overcurrents, short-circuit protection also obtains very big improvement; particularly the current-limiting circuit technology is very ripe; short-circuit protection generally is to adopt the triggering signal that is used as protective circuit on the former limit of Switching Power Supply by the peak current that uses current sense resistor, current sensor, current transformer to detect former limit; when short circuit appears in output; primary current can increase severely or primary current when surpassing the threshold values of protective circuit; protective circuit is started to control, thereby the output of turn-offing rectifier realizes defencive function.
All there are same characteristics altogether in overcurrent in the Switching Power Supply and the short-circuit protection circuit at present; need to gather the current data on former limit exactly; carry out computing by operational amplifier; control protection electric circuit triggers then; start to the protective circuit action from Switching Power Supply and need the regular hour; during this period; line current is very large; the heat that produces is also considerable; when long short circuit appears in load; current-limiting circuit in the Switching Power Supply is in the scope of design load at the control output current; when being the output short circuit; voltage is zero (main transformer substantially; the peak current of rectifier diode and outputting inductance is considerably beyond design load); this moment power supply be output into constant current state; average output power descends; detected average current of primary current and peak current also descend; when the primary current testing circuit is easy to cause protective circuit to be failure to actuate because of the reason of the error amount of device; therefore the rectifier diode of output and outputting inductance can seriously generate heat; if output exists short trouble will cause main transformer for a long time; rectifier diode and outputting inductance burn, and cause bigger accident.Therefore, traditional overcurrent, short-circuit protection all exist all quite accurate to each parameter of circuit element, the circuits for triggering response speed lags behind, complicated or the like the shortcoming of debugging.
The utility model content
The purpose of this utility model provide a kind of make Switching Power Supply move the protective circuit of switch power source of safety and stablization more.
For solving technical problem of the present utility model; the utility model discloses a kind of Switching Power Supply short-circuit protection circuit; comprise pwm control circuit, short circuit monitoring impulse circuit, RC integrating circuit, close DC/DC converter control circuit and output short-circuit supervisory circuit; pwm control circuit, short circuit monitoring impulse circuit, RC integrating circuit, close the DC/DC converter control circuit and the output short-circuit supervisory circuit connects successively, the output short-circuit supervisory circuit is connected to power supply output.
Compared with prior art, Switching Power Supply of the present utility model does not need the peak-current signal control short circuit on former limit, omitted complicated debug process in process of production, the utility model can be set arbitrarily the condition of output protection, do not need to regulate, therefore adopt the utility model more to meet modernized industrial production requirement rapidity, controllability; The utility model circuit is in the supervision output state at ordinary times, when short circuit or output abnormality occurring, can close the modulation signal output protection of pwm control circuit at once, thereby turn-off the DC/DC converter, in the middle of closing pwm signal, there is not operation link from detecting output abnormality, so response speed is fast more a lot of than traditional peak current protection, more meets the fast requirement of short circuit current response speed, the fail safe that has improved Switching Power Supply; In addition, the magnetic element that does not need in the utility model to regulate maybe needs resistance, the electric capacity regulated, employing all be conventional electronic material, material is not had any specific (special) requirements, with the short-circuit protection of the routine more material cost of specific energy saving mutually.
Description of drawings
Fig. 1 is the theory diagram of Switching Power Supply short-circuit protection circuit of the present utility model.
Embodiment
As shown in Figure 1, Switching Power Supply short-circuit protection circuit of the present utility model comprises pwm control circuit, short circuit monitoring impulse circuit, RC integrating circuit, closes DC/DC converter control circuit and output short-circuit supervisory circuit.
Pwm control circuit is connected with the short circuit monitoring impulse circuit.Pwm pulse signal obtains monitoring pulse signal through the shaping of short circuit monitoring impulse circuit.The short circuit monitoring impulse circuit is connected with the RC integrating circuit, for the RC integrating circuit provides the control signal source.The RC integrating circuit links to each other with the output short-circuit supervisory circuit, for the output short-circuit supervisory circuit provides the monitoring pulse, with the operating state of control DC/DC converter.Close the DC/DC converter control circuit and be connected with the output short-circuit supervisory circuit, whether the output state of pilot switch power supply is normal.
Pwm control circuit is connected with the short circuit monitoring impulse circuit, the short circuit monitoring impulse circuit generates the short circuit monitoring clock pulse according to the pwm pulse signal that pwm control circuit is, output short-circuit supervisory circuit clock is in view of the above judged the electric current of output rectifier and filter output, thereby judge whether short circuit, if shutdown signal is then sent in short circuit, close pwm control circuit immediately, thereby close the output of DC/DC converter, also just closed Switching Power Supply.
All require short trouble to remove the back according to switch power supply system and recover output automatically, the utility model is provided with the RC integrating circuit between pwm control circuit and short-circuit protection circuit.When short trouble did not appear in output, this pulse signal triggered the energy that drives protection device for protective circuit provides; When the protection fault occurring; close the output of PWM controller at once, thus the output of off switch power supply, because of closing of pwm control circuit do not have modulation signal output; the monitoring clock of protective circuit also disappears thereupon, and come for circuits for triggering to provide trigger current by the electric capacity on the RC integrating circuit this moment.
Compared with prior art, Switching Power Supply of the present utility model does not need the peak-current signal control short circuit on former limit, omitted in process of production complicated debug process, the utility model can Set arbitrarily to the condition of output protection, do not need to regulate, therefore adopt the utility model more to meet modernized industrial production requirement rapidity, controllability; The utility model circuit is in the supervision output state at ordinary times, when short circuit or output abnormality occurring, can close at once the modulation signal output protection of pwm control circuit, thereby turn-off the DC/DC converter, in the middle of closing pwm signal, there is not operation link from detecting output abnormality, so response speed is fast more a lot of than traditional peak point current protection, more meets the requirement of short circuit current fast response time, has improved the security of Switching Power Supply; In addition, the magnetic element that does not need in the utility model to regulate maybe needs resistance, the electric capacity regulated, employing all be conventional electronic material, material is not had any specific (special) requirements, with the more material cost of short-circuit protection phase specific energy saving of routine.
Claims (1)
1. Switching Power Supply short-circuit protection circuit; it is characterized in that: comprise pwm control circuit, short circuit monitoring impulse circuit, RC integrating circuit, close DC/DC converter control circuit and output short-circuit supervisory circuit; pwm control circuit, short circuit monitoring impulse circuit, RC integrating circuit, close the DC/DC converter control circuit and the output short-circuit supervisory circuit connects successively, the output short-circuit supervisory circuit is connected to power supply output.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010201015868U CN201639273U (en) | 2010-01-22 | 2010-01-22 | Switching power supply short-circuit protective circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010201015868U CN201639273U (en) | 2010-01-22 | 2010-01-22 | Switching power supply short-circuit protective circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN201639273U true CN201639273U (en) | 2010-11-17 |
Family
ID=43083779
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2010201015868U Expired - Fee Related CN201639273U (en) | 2010-01-22 | 2010-01-22 | Switching power supply short-circuit protective circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN201639273U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106897177A (en) * | 2017-02-21 | 2017-06-27 | 惠州Tcl移动通信有限公司 | A kind of method and system based on mobile terminal system of fingerprints short-circuit detecting and protection |
-
2010
- 2010-01-22 CN CN2010201015868U patent/CN201639273U/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106897177A (en) * | 2017-02-21 | 2017-06-27 | 惠州Tcl移动通信有限公司 | A kind of method and system based on mobile terminal system of fingerprints short-circuit detecting and protection |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102790374B (en) | Short circuit protection circuit | |
| CN102709901B (en) | Current transformer over-voltage protection method and device | |
| CN104483883A (en) | Control unit for relays | |
| CN101997459A (en) | DC oil pump motor soft start control device | |
| CN103558541B (en) | The self checking method of Safety output circuit | |
| CN104158152B (en) | A kind of motor driver protection circuit and means of defence | |
| CN103529876B (en) | Dry-type transformer temperature control device with self-detecting function and working method thereof | |
| CN105929220A (en) | Over-current detection circuit | |
| CN204230865U (en) | A kind of motor protecting device | |
| CN201639273U (en) | Switching power supply short-circuit protective circuit | |
| CN102931034A (en) | Leakage circuit breaker | |
| CN203535514U (en) | A dry-type transformer temperature control device with a self-inspection function | |
| CN202679748U (en) | LED driving power supply circuit | |
| CN202749309U (en) | Residual current circuit breaker | |
| CN203205830U (en) | Resettable overvoltage and under-voltage protector with leakage protection function | |
| CN105356735B (en) | A kind of open loop protection circuit for reducing output voltage overshoot | |
| CN103208774B (en) | A kind of intrinsic safety electric source short-circuit protection circuit | |
| CN203127983U (en) | Lifting electromagnet short-circuit protection device controlled by programmable logic controller (PLC) | |
| CN202997964U (en) | Double-end flyback type switch power supply with input overcurrent and power-down protection | |
| CN203276459U (en) | Electrical fire monitoring detector having overvoltage under-voltage detecting and protective functions | |
| CN202076774U (en) | Energy-saving undervoltage/overvoltage protective device | |
| CN202917947U (en) | Electric leakage circuit breaker | |
| CN102288808A (en) | LED (light-emitting diode) over-current detection circuit and LED driving control circuit | |
| CN100367592C (en) | Detecting and protecting method and device for exception of circuit | |
| CN203748088U (en) | Light controlling means |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20101117 Termination date: 20130122 |