CN203896189U - Power adapter control circuit for monitor - Google Patents
Power adapter control circuit for monitor Download PDFInfo
- Publication number
- CN203896189U CN203896189U CN201420191851.4U CN201420191851U CN203896189U CN 203896189 U CN203896189 U CN 203896189U CN 201420191851 U CN201420191851 U CN 201420191851U CN 203896189 U CN203896189 U CN 203896189U
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- China
- Prior art keywords
- circuit
- resistance
- output
- power supply
- control circuit
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B70/00—Technologies for an efficient end-user side electric power management and consumption
- Y02B70/10—Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes
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Abstract
The utility model provides a power adapter control circuit for a monitor. The power adapter control circuit comprises a power input circuit, a rectification filter circuit, a power amplification circuit, a PWM control circuit, a transformer, a secondary synchronous rectification circuit, an isolation voltage feedback circuit, an auxiliary power supply circuit and an output filtering circuit. The power input circuit is connected with the rectification filter circuit. The output end of the rectification filter circuit is connected with the transformer. The secondary end of the transformer is connected with the secondary synchronous rectification circuit. The output end of the secondary synchronous rectification circuit is connected with the output filtering circuit. The isolation voltage feedback circuit is connected with the output filtering circuit. Output ends of the isolation voltage feedback circuit and the auxiliary power supply circuit are connected with the PWM control circuit. The output end of the PWM control circuit is connected with the power amplification circuit. The output end of the power amplification circuit is connected with the transformer. The control circuit is simple in structure, low in manufacture cost and little in standby power consumption.
Description
Technical field
The utility model relates to a kind of power supply adaptor, particularly a kind of power supply adaptor control circuit for watch-dog.
Background technology
Watch-dog refers to the general name of utilizing shooting memory device that video, audio signal are included and stored.Along with day by day universal in civilian and commercial use of closed-circuit control, watch-dog is widely used in various fields, for business administration and social security play the effect escorting.
What watch-dog adopted at present is that external power supply is that watch-dog is powered, by power supply adaptor, extraneous 220V is converted to the direct current supply voltage that meets watch-dog, Switching Power Supply great majority in current power supply adaptor are on the market all to adopt common hard switching PWM control mode design, have the problem that switching noise is large, power consumption large, conversion efficiency is not high.
Utility model content
The utility model, for the technical problem of above-mentioned existence, has proposed a kind of power supply adaptor control circuit for watch-dog, solves power supply adaptor power consumption in use greatly and the not high problem of conversion efficiency.
The technical solution of the utility model is: a kind of power supply adaptor control circuit for watch-dog, comprise: power supply input circuit, current rectifying and wave filtering circuit, power amplification circuit, pwm control circuit, transformer, secondary synchronization rectification circuit, isolation voltage feedback circuit, auxiliary power circuit and output filter circuit, the output of described power supply input circuit connects described current rectifying and wave filtering circuit, the output of described current rectifying and wave filtering circuit is connected with transformer, the secondary end of described transformer connects secondary synchronization rectification circuit, the output of described secondary synchronization rectification circuit connects described output filter circuit, the input of described isolation voltage feedback circuit is connected with described output filter circuit, described isolation voltage feedback circuit output connect pwm control circuit, the output of described pwm control circuit connects described power amplification circuit, the output connection transformer of described power amplification circuit, described auxiliary power circuit is connected with described pwm control circuit.
Further; described power supply adaptor control circuit also comprises: overcurrent-overvoltage protecting circuit; described overcurrent-overvoltage protecting circuit is connected with the output of described current rectifying and wave filtering circuit, and described overcurrent-overvoltage protecting circuit is made up of capacitor C b, resistance R b1, resistance R b2, resistance R b3 and resistance R b4.
Further, described power supply adaptor control circuit also comprises: common mode rejection circuit, and the input of described common mode rejection circuit is connected with described power supply input circuit, and the output of described common mode rejection circuit connects described current rectifying and wave filtering circuit.
Further, the output of described power amplification circuit arranges peak voltage absorbing circuit, described power amplification circuit is that MOSFET power switch pipe Q1 and the current sampling circuit that is made up of resistance R 7, resistance R 8, resistance R 10 and resistance R s form, and described peak voltage absorbing circuit is made up of diode Dsn, capacitor C sn and resistance R sn.
Further, described auxiliary power circuit is made up of diode Da, resistance R a and capacitor C a, described secondary voltage feedback circuit optocoupler IC2, voltage-stabiliser tube IC3, resistance R 15, resistance R 16 and resistance R 17 form, described secondary commutation synchronization control circuit, the compositions such as T2, Dsc, Rsc and Qsc, described rectification output filter circuit Qr, Co, Cp and Lp composition.
The beneficial effects of the utility model: extraneous power supply enters into current rectifying and wave filtering circuit by power supply input circuit alternating voltage is carried out to rectifying and wave-filtering, the utility model carries out rectifying and wave-filtering by secondary synchronization rectification circuit and output filter circuit to the direct voltage of output, on output filter circuit, connecting isolation voltage feedback circuit controls output filter circuit signal feedback to pwm control circuit to power amplification circuit, by FEEDBACK CONTROL, the voltage of output is detected power amplification circuit is controlled, reduce power consumption, this control circuit simple in structure, low cost of manufacture, stand-by power consumption is little.
Brief description of the drawings
Fig. 1 is a kind of power supply adaptor control circuit structured flowchart for watch-dog the utility model proposes;
Fig. 2 is a kind of power supply adaptor control circuit figure for watch-dog the utility model proposes.
Embodiment
Referring to Fig. 1, it is a kind of power supply adaptor control circuit structure chart for watch-dog the utility model proposes.
As shown in Figure 1, a kind of power supply adaptor control circuit for watch-dog, comprise: power supply input circuit, current rectifying and wave filtering circuit, power amplification circuit, pwm control circuit, transformer, secondary synchronization rectification circuit, isolation voltage feedback circuit, auxiliary power circuit and output filter circuit, the output of described power supply input circuit connects described current rectifying and wave filtering circuit, the output of described current rectifying and wave filtering circuit is connected with transformer, the secondary end of described transformer connects secondary synchronization rectification circuit, the output of described secondary synchronization rectification circuit connects described output filter circuit, the input of described isolation voltage feedback circuit is connected with described output filter circuit, described isolation voltage feedback circuit output connect pwm control circuit, the output of described pwm control circuit connects described power amplification circuit, the output connection transformer of described power amplification circuit, described auxiliary power circuit is connected with described pwm control circuit.
Extraneous power supply enters into current rectifying and wave filtering circuit by power supply input circuit alternating voltage is carried out to rectifying and wave-filtering, by transformer to output secondary voltage, by secondary synchronization rectification circuit and output filter circuit, the direct voltage of output is carried out to rectifying and wave-filtering, on output filter circuit, connecting isolation voltage feedback circuit controls output filter circuit signal feedback to pwm control circuit to power amplification circuit, by FEEDBACK CONTROL, this control circuit is simple in structure, low cost of manufacture, stand-by power consumption are little.
Fig. 2 is a kind of power supply adaptor control circuit figure for watch-dog the utility model proposes.
Referring to Fig. 2; described power supply adaptor control circuit also comprises: overcurrent-overvoltage protecting circuit; described overcurrent-overvoltage protecting circuit is connected with the output of described current rectifying and wave filtering circuit, and described overcurrent-overvoltage protecting circuit is made up of capacitor C b, resistance R b1, resistance R b2, resistance R b3 and resistance R b4.
Resistance R b4 is used for setting the degree of depth of overload compensation, can ensure that in conjunction with current sampling resistor Rs and primary inductance value power supply adaptor has constant overload power point in full input voltage range.Overcome general power supply adaptor overload power point in the time of high low input and be difficult to the shortcoming that keeps constant, thereby avoided can crossing because power is higher the problem of cause thermal damage power supply adaptor in the time that high input voltage transships.
Described power supply input circuit is that negative temperature is that resistance and VSR1 piezo-resistance form by F1 fuse, TH1, described current rectifying and wave filtering circuit is made up of rectifier bridge BD1, capacitor C dc, capacitor C 4, the input of described common mode rejection circuit is connected with external power supply, and the output of described common mode rejection circuit connects described power supply input circuit.
F1 is alternating-current fuse silk, and its effect is in the time that the inner generation of power supply is abnormal, prevents that large short circuit current from appearring in power input; Negative temperature coefficient resister TH1 Main Function is the impulse current while reducing power supply start; Piezo-resistance VSR1 Main Function is the surge voltage absorbing on incoming line, prevents that the device of power supply inside from being damaged by overvoltage.
Be made up of the EMI common mode rejection circuit of power input together with common mode inductance L1 capacitor C 1, C2, its effect one is the differential mode noise of attenuator switch power supply, reduces the emittance of EMI.Its effect two is the common-mode noise amplitudes that suppress Switching Power Supply, reduces the conducted interference of Switching Power Supply.
Cdc Main Function is to input voltage smothing filtering, and filtering ripple voltage provides metastable direct voltage, and C4 Main Function is filtering HF switch noise, improves the transport properties of power supply.
The output of described power amplification circuit arranges peak voltage absorbing circuit, described power amplification circuit is that MOSFET power switch pipe Q1 and the current sampling circuit that is made up of resistance R 7, resistance R 8, resistance R 10 and resistance R s form, described peak voltage absorbing circuit is made up of diode Dsn, capacitor C sn and resistance R sn, its Main Function is the rising edge peak voltage energy producing in the time turn-offing for absorbing MOSFET power switch pipe, reduce peak voltage amplitude, prevent power switch pipe over-voltage breakdown.
Described auxiliary power circuit is made up of diode Da, resistance R a and capacitor C a, described secondary voltage feedback circuit optocoupler IC2, voltage-stabiliser tube IC3, resistance R 15, resistance R 16 and resistance R 17 form, described secondary commutation synchronization control circuit, the compositions such as T2, Dsc, Rsc and Qsc, described rectification output filter circuit Qr, Co, Cp and Lp composition.
Described pwm control circuit adopts NCP1337 chip, by increasing accessory power supply, it is powered, and realizes output over-voltage defencive function thereby monitor output voltage by accessory power supply voltage simultaneously.
In secondary synchronization rectification circuit, T2 is current transformer, Qsc, Qsc1 and Qsc2 are common PNP, NPN triode, resistance R sc resets for current transformer core, when there is electric current secondary loop in the time that rectification MOSFET parasitic diode passes through the former limit of T2, the secondary of T2 will produce induced voltage, this voltage produces a driving voltage again through Qsc after Dsc rectification on Rsc1, Qsc1 and Qsc2 electric current amplify rear drive rectification MOSFET conducting, because quasi-resonance power supply is to be operated in non-continuous mode, so control circuit must be just to turn-off rectification MOSFET pipe by 1 o'clock at rectification MOSFET pipe drain current, the turn-off power loss of rectification MOSFET pipe is almost reduced to zero like this, so greatly promote the effect of synchronous rectification.
In 12 volts of rectification output filter circuits that form together with Lp at Qr, Co, Cp, MOSFET pipe Qr substitutes traditional Schottky diode and does rectification, because the conduction loss of MOSFET pipe is much smaller than Schottky diode, thereby improved the conversion efficiency of whole power supply, especially in the time of High-current output, the effect of improved efficiency is more obvious.And Co, Cp and Lp have just formed the Л type filter circuit of 12 volts of direct current outputs, the Main Function of Co, Cp is smothing filtering, IC3 is reference voltage source, the reference voltage of 12 volts of output voltages is provided, resistance R 15, R16 are used for setting the size of output voltage, resistance R 17 provides the operating current of IC2, and resistance R 18 provides direct current biasing for IC3.
Claims (5)
1. the power supply adaptor control circuit for watch-dog, comprise: power supply input circuit, current rectifying and wave filtering circuit, power amplification circuit, pwm control circuit, transformer, secondary synchronization rectification circuit, isolation voltage feedback circuit, auxiliary power circuit and output filter circuit, the output of described power supply input circuit connects described current rectifying and wave filtering circuit, the output of described current rectifying and wave filtering circuit is connected with transformer, the secondary end of described transformer connects secondary synchronization rectification circuit, the output of described secondary synchronization rectification circuit connects described output filter circuit, the input of described isolation voltage feedback circuit is connected with described output filter circuit, described isolation voltage feedback circuit output connect pwm control circuit, the output of described pwm control circuit connects described power amplification circuit, the output connection transformer of described power amplification circuit, described auxiliary power circuit is connected with described pwm control circuit.
2. a kind of power supply adaptor control circuit for watch-dog according to claim 1; it is characterized in that; described power supply adaptor control circuit also comprises: overcurrent-overvoltage protecting circuit; described overcurrent-overvoltage protecting circuit is connected with the output of described current rectifying and wave filtering circuit, and described overcurrent-overvoltage protecting circuit is made up of capacitor C b, resistance R b1, resistance R b2, resistance R b3 and resistance R b4.
3. a kind of power supply adaptor control circuit for watch-dog according to claim 1, it is characterized in that, described power supply adaptor control circuit also comprises: common mode rejection circuit, the input of described common mode rejection circuit is connected with described power supply input circuit, and the output of described common mode rejection circuit connects described current rectifying and wave filtering circuit.
4. a kind of power supply adaptor control circuit for watch-dog according to claim 1, it is characterized in that, the output of described power amplification circuit arranges peak voltage absorbing circuit, described power amplification circuit is that MOSFET power switch pipe Q1 and the current sampling circuit that is made up of resistance R 7, resistance R 8, resistance R 10 and resistance R s form, and described peak voltage absorbing circuit is made up of diode Dsn, capacitor C sn and resistance R sn.
5. a kind of power supply adaptor control circuit for watch-dog according to claim 1, it is characterized in that, described auxiliary power circuit is made up of diode Da, resistance R a and capacitor C a, described secondary voltage feedback circuit optocoupler IC2, voltage-stabiliser tube IC3, resistance R 15, resistance R 16 and resistance R 17 form, described secondary commutation synchronization control circuit, the compositions such as T2, Dsc, Rsc and Qsc, described rectification output filter circuit Qr, Co, Cp and Lp composition.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420191851.4U CN203896189U (en) | 2014-04-18 | 2014-04-18 | Power adapter control circuit for monitor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420191851.4U CN203896189U (en) | 2014-04-18 | 2014-04-18 | Power adapter control circuit for monitor |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN203896189U true CN203896189U (en) | 2014-10-22 |
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ID=51722541
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201420191851.4U Expired - Fee Related CN203896189U (en) | 2014-04-18 | 2014-04-18 | Power adapter control circuit for monitor |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN203896189U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105375762A (en) * | 2015-12-15 | 2016-03-02 | 深圳市华星光电技术有限公司 | Buck-boost conversion circuit, power source management module and liquid crystal drive device |
| CN106300994A (en) * | 2016-10-14 | 2017-01-04 | 成都前锋电子仪器有限责任公司 | A kind of circuit for power conversion |
-
2014
- 2014-04-18 CN CN201420191851.4U patent/CN203896189U/en not_active Expired - Fee Related
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105375762A (en) * | 2015-12-15 | 2016-03-02 | 深圳市华星光电技术有限公司 | Buck-boost conversion circuit, power source management module and liquid crystal drive device |
| CN105375762B (en) * | 2015-12-15 | 2018-03-13 | 深圳市华星光电技术有限公司 | A kind of buck translation circuit, power management module and LCD drive g device |
| CN106300994A (en) * | 2016-10-14 | 2017-01-04 | 成都前锋电子仪器有限责任公司 | A kind of circuit for power conversion |
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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 |
Granted publication date: 20141022 Termination date: 20150418 |
|
| EXPY | Termination of patent right or utility model |