CN201781412U - Direct current power supply circuit - Google Patents
Direct current power supply circuit Download PDFInfo
- Publication number
- CN201781412U CN201781412U CN2010202588072U CN201020258807U CN201781412U CN 201781412 U CN201781412 U CN 201781412U CN 2010202588072 U CN2010202588072 U CN 2010202588072U CN 201020258807 U CN201020258807 U CN 201020258807U CN 201781412 U CN201781412 U CN 201781412U
- Authority
- CN
- China
- Prior art keywords
- triode
- power supply
- supply circuit
- circuit
- input
- 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 - Lifetime
Links
Images
Landscapes
- Direct Current Feeding And Distribution (AREA)
Abstract
The utility model provides a soft-start circuit of a direct current power supply, and the circuit comprises the input end for inputting direct current, a power supply control switch triode, a push triode, a negative feedback resistor and a feedback capacitor, wherein an input pole of the power supply control switch triode is connected to the input end of the circuit, a control pole is connected with the input pole of the push triode and connected to the input end of the circuit, and an output pole is connected to a load; and the output pole of the push triode is grounded through the negative feedback resistor, and the output pole is connected to the output end of the power supply control triode through the feedback capacitor. Negative feedback of the feedback capacitor can lead the push triode to play a certain retardation role, thereby avoiding the secondary powering-up phenomenon caused by direct feedback, further providing smaller impedance for a discharge channel and avoiding fast upper and lower electric shock of a power supply circuit to the load.
Description
Technical field
The utility model relates to a kind of DC power supply circuit, particularly a kind of DC power supply soft starting circuit.
Background technology
In some electric power supply circuit, much all need to use DC power supply, and DC power supply is when powering on or powering on by control switch, because effects such as load capacitance, bigger impulse current of moment generation can powered up, if do not add restriction, impulse current tends to some responsive electric equipments or device are constituted a threat to.When powering, just be faced with the threat of impulse current such as the screen of the LCD in the LCD television set.Therefore; need a kind of power circuit of design, it not only can be controlled whether power on, but also can suppress impulse current; the slope that powers on by certain is powered up gradually, so just can effectively avoid power supply for the impact of responsive electric equipments such as LCD screen and play a protective role.In addition, this power circuit such as for improving the switching on and shutting down sound of power amplifier, also needs this circuit that slowly powers on by certain slope also in some special direct current electricity consumption occasions.
In order to address the above problem, industry has designed various power circuits, yet these circuit are not comparatively complicated loaded down with trivial details, is exactly that respective capabilities is poor fast, or the problem that does not have fine solution secondary to power on.The so-called secondary problem that powers on, refer to when circuit control end level is in electronegative potential, the DC power supply of retentive control load just is in off state, this is DC power supply arrive suddenly (Powerin), design the fast powering-up phenomenon that bad circuit tends to produce a short time, this powers on is unnecessary, also is extremely harmful, and it has run counter to the original intention of DC power supply soft starting circuit design.For this reason, need to consider a kind of brand-new power circuit, can effectively solve secondary and power up problem.
The utility model content
The purpose of this utility model is to provide a kind of soft start DC power supply circuit, is intended to solve the impact of the fast powering-up that exists in the prior art and the secondary problem that powers on.
The utility model is to realize like this, a kind of DC power supply circuit, the input, power control switch triode, promotion triode, the negative feedback resistor that comprise input dc power, feedback capacity, the power control switch triode input utmost point is connected to the input of this circuit, the control utmost point extremely links to each other with the input that promotes triode, and is connected to the input of circuit, and output stage exports load to; Promote the triode output stage by this negative feedback resistor ground connection, and output stage is connected to the output of power supply control triode by feedback capacity.
More specifically, this DC power supply circuit also comprises pull-up resistor, and this power control switch triode is the PMOS pipe, and this promotion triode is a NPN type triode, the source electrode of this NPN type triode links to each other with the grid of this PMOS pipe, and is connected to this input by this pull-up resistor.
More specifically, this emitter-base bandgap grading that promotes triode passes through this negative feedback resistor ground connection, and is connected to the drain electrode of this power control switch triode by this feedback capacity.
More specifically, this DC power supply circuit comprises a control end, first biasing resistor and second biasing resistor, and this control end is by first resistance and second grounding through resistance of this series connection, and the node of this first resistance and second resistance is connected to the base stage of this promotion triode.
More specifically, feedback resistance is 470 Europe, and the base circuit of this promotion triode is 10uA.
More specifically, feedback capacity C1 is 100NF or 220NF or 470NF.
More specifically, the output of control end is the direct voltage of 3.3V.
More specifically, the resistance value of pull-up resistor is more than or equal to 22K ohm.
Problem that the utility model overcomes that fast powering-up in the existing DC power supply circuit impacts and secondary powers on is utilized negative-feedback technology, and feedback capacity is added to the emitter that promotes triode, and emitter adds a negative feedback resistor ground connection simultaneously.Because the negative feedback of feedback capacity, when the DC power supply control end is opened, certain retardation is arranged, do the secondary of having avoided direct feedback to bring like this and add electrical phenomena, and also provide less impedance, can power supply circuits have been impacted by the quick power-on and power-off of load to discharge channel.
Description of drawings
Fig. 1 is the circuit diagram of the utility model DC power supply circuit.
Embodiment
In order to make the purpose of this utility model, technical scheme and advantage clearer,, the utility model is further elaborated below in conjunction with drawings and Examples.Should be appreciated that specific embodiment described herein only in order to explanation the utility model, and be not used in qualification the utility model.
Seeing also Fig. 1, is the circuit diagram of the utility model power circuit.This power circuit comprises input POWERIN, control end CONTROL, load end LOAD, power supply control triode Q1, promotion triode Q2, negative feedback resistor R4, feedback capacity C1, promotion triode Q2, ground level biasing resistor R2 and the R3 of input dc power, the control utmost point (grid G or ground level) the pull-up resistor R1 of power supply control triode Q1.
In the circuit diagram of present embodiment, for the ease of giving an example, power supply control triode Q1 is the PMOS pipe, and promoting triode Q2 is the positive-negative-positive triode, and the switch element that can realize similar functions of other types can be replaced above-mentioned two kinds of switch elements.
The source electrode of power supply control triode Q1 meets input POWERIN, and grid meets voltage input end POWERIN by pull-up resistor R1, and simultaneously, grid also links to each other with the collector electrode that promotes triode Q2, and drain electrode meets load end LOAD.Promote triode Q2 emitter by negative feedback resistor R4 ground connection, and be connected to the drain electrode of power supply control triode Q1 by feedback capacity C1.Control end CONTROL is by the biasing resistor R2 and the R3 ground connection of series connection, and the node of R2 and R3 is connected to the base stage that promotes triode Q2.
The basic functional principle of this power circuit is: for PMOS power supply control triode Q1, when its grid was low level, the PMOS pipe was in conducting state.And promote triode Q2 is the passage that level conversion is provided to the grid of power supply control triode Q1.The concrete work of this circuit is as follows: control end CONTROL sends control signal, generally is the DC level of 3.3V, after the triode conversion, just can be converted into 0 one V
PowerinBetween signal (V
PowerinBe the voltage that POWERIN exports power supply control triode Q1 drain electrode to), this signal grid of PMOS power supply control triode Q1 just is needed.The VGS required voltage of PMOS pipe is very little, such as 2-10V, suitably increases the emitter resistance that promotes triode, suitably reduces the control voltage of the grid of power supply control triode Q1, to not influence of whole power supply control.For example, POWERIN is 12V, and the VGS specifications of PMOS triode require to be 4.5V, the emitter feedback resistance is 470 Europe, control promotes the base current of triode Q2, and making the collector voltage that promotes triode Q2 is 0.3-1.5V, and then the VGS of PMOS triode Q1 is 11.7V one 10.5V.When promote triode Q2 ground level signal by low level when high level changes, Q2 is by by becoming conducting, power supply is controlled the controlled stage of triode Q1 at this moment, grid in the present embodiment, dragged down, power supply control this moment triode Q1 satisfies the condition of conducting, becomes conducting state.On feedback capacity, because the power supply control triode Q1 voltage of conducting gradually can form the conducting that the electric current that rises gradually removes to stop promotion triode Q2, just form the decline gradually of the controlled stage G of power supply switch tube Q1, like this, just can impel the voltage of the drain D of power supply control triode Q1 to rise gradually.
The utility model has utilized negative-feedback technology, and feedback capacity is added to the emitter that promotes triode Q2, and emitter adds a negative feedback resistor R4 ground connection simultaneously.Because the negative feedback of feedback capacity C1, when the DC power supply control end is opened, certain retardation is arranged, do the secondary of having avoided direct feedback to bring like this and add electrical phenomena, and also provide less impedance, can power supply circuits have been impacted by the quick power-on and power-off of load to discharge channel.
In use, the operate as normal that satisfies power supply control triode Q1 is a first condition, to metal-oxide-semiconductor then for VDS will meet the requirement of device specifications, to general triode then the variation of base current to guarantee to drive the pipe operate as normal.When specifically being provided with, the electric current setting that promotes triode ground level Q2 is an emphasis, base current is too big, then feedback current is not enough to offset its zooming trend, from but the load power source rising edge stage exists and to rise fast and influence the voltage slope of load end in fact, the too little promotion ability that then can influence it to power supply control triode Q1 of feedback current is the key of soft startup circuit for power supply operate as normal so regulate the numerical value of base current.Generally for the circuit of PMOS pipe for power supply control, base current is under the situation in 470 Europe promoting pipe emitter degeneration resistance R 4, and it is suitable getting about 10uA, in this case, can reach several milliseconds delay, time of delay and load weight are irrelevant; The size of feedback capacity C1 is tested by following several groups and verified value, and experimental data is: when feedback capacity C1 was 100NF, be 2.5ms time of delay; When feedback capacity was 220NF, time of delay was when being 4.5ms; When feedback capacity was 470NF, be 10ms time of delay.Time of delay may be according to selected triode situation difference to some extent.Pull-up resistor R1 then suitably gets more greatly, such as 22k or bigger if power supply control triode is a metal-oxide-semiconductor.If general triode will be seen back level electric current and decides.General big electric current (more than the 0.5A) is suitable uses metal-oxide-semiconductor, and little electric current then just gets final product with general low-power transistor.
The above only is preferred embodiment of the present utility model; not in order to restriction the utility model; all any modifications of within spirit of the present utility model and principle, being done, be equal to and replace and improvement etc., all should be included within the protection range of the present utility model.
Claims (8)
1. DC power supply circuit, the input, power control switch triode, promotion triode, the negative feedback resistor that comprise input dc power, feedback capacity, the power control switch triode input utmost point is connected to the input of this circuit, the control utmost point extremely links to each other with the input that promotes triode, and be connected to the input of circuit, output stage exports load to; Promote the triode output stage by this negative feedback resistor ground connection, and output stage is connected to the output of power supply control triode by feedback capacity.
2. DC power supply circuit as claimed in claim 1, it is characterized in that: this DC power supply circuit also comprises pull-up resistor, this power control switch triode is the PMOS pipe, this promotion triode is a NPN type triode, the source electrode of this NPN type triode links to each other with the grid of this PMOS pipe, and is connected to this input by this pull-up resistor.
3. DC power supply circuit as claimed in claim 2 is characterized in that: the emitter-base bandgap grading of this promotion triode passes through this negative feedback resistor ground connection, and is connected to the drain electrode of this power control switch triode by this feedback capacity.
4. DC power supply circuit as claimed in claim 3, it is characterized in that: this DC power supply circuit comprises a control end, first biasing resistor and second biasing resistor, this control end is by first resistance and second grounding through resistance of this series connection, and the node of this first resistance and second resistance is connected to the base stage of this promotion triode.
5. DC power supply circuit as claimed in claim 3 is characterized in that: feedback resistance is 470 Europe, and the base circuit of this promotion triode is 10uA.
6. DC power supply circuit as claimed in claim 3 is characterized in that: feedback capacity C1 is 100NF or 220NF or 470NF.
7. DC power supply circuit as claimed in claim 2 is characterized in that: the output of control end is the direct voltage of 3.3V.
8. DC power supply circuit as claimed in claim 2 is characterized in that: the resistance value of pull-up resistor is more than or equal to 22K ohm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010202588072U CN201781412U (en) | 2010-07-14 | 2010-07-14 | Direct current power supply circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010202588072U CN201781412U (en) | 2010-07-14 | 2010-07-14 | Direct current power supply circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN201781412U true CN201781412U (en) | 2011-03-30 |
Family
ID=43794614
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2010202588072U Expired - Lifetime CN201781412U (en) | 2010-07-14 | 2010-07-14 | Direct current power supply circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN201781412U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109474180A (en) * | 2018-11-05 | 2019-03-15 | 四川神坤电液控制技术有限公司 | Non-isolated buck-boost power supply circuits and power modules |
| CN111313674A (en) * | 2019-11-06 | 2020-06-19 | 北京比特大陆科技有限公司 | Power-on control circuit and electronic equipment with same |
-
2010
- 2010-07-14 CN CN2010202588072U patent/CN201781412U/en not_active Expired - Lifetime
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109474180A (en) * | 2018-11-05 | 2019-03-15 | 四川神坤电液控制技术有限公司 | Non-isolated buck-boost power supply circuits and power modules |
| CN111313674A (en) * | 2019-11-06 | 2020-06-19 | 北京比特大陆科技有限公司 | Power-on control circuit and electronic equipment with same |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101325411B (en) | Slow starting circuit for electrifying DC power supply | |
| CN106774772B (en) | A kind of hot plug module is for electric installation, method and system | |
| CN101562443B (en) | Overvoltage protection circuit and liquid crystal display device drive circuit | |
| CN102386898B (en) | Reset circuit | |
| CN205960951U (en) | Power supply circuit | |
| CN103034608B (en) | Plug-and-play circuit, interface circuit and electronic equipment assembly | |
| CN201569970U (en) | Power soft-start device suitable for USB interface equipment | |
| CN201629569U (en) | Over-voltage protection circuit of USB interface | |
| CN201629808U (en) | Impact noise eliminating circuit and flat panel television | |
| CN201781412U (en) | Direct current power supply circuit | |
| CN206211501U (en) | A kind of locked protection circuit of new output overvoltage | |
| CN101471564B (en) | Voltage control circuit | |
| CN105652994A (en) | Voltage switching device | |
| CN110571773B (en) | Protective circuit | |
| CN206559074U (en) | A kind of power supply circuit and mobile terminal | |
| CN104300946A (en) | Quick power-down module of low-voltage equipment | |
| CN210780130U (en) | Power-off control circuit | |
| CN205142167U (en) | Time delay outage reset circuit | |
| CN202306374U (en) | Electrified current control circuit for chips | |
| CN107340846B (en) | Power-down prevention logic circuit and notebook computer | |
| CN103746358A (en) | Surge suppression circuit, switching device and set-top box | |
| CN101872229A (en) | Computer power and power state signal generating circuit thereon | |
| CN112018839B (en) | Load detection circuit | |
| CN111224648B (en) | Power-on and power-off reset control circuit without static power consumption | |
| CN205490464U (en) | Delay circuit of repid discharge |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CX01 | Expiry of patent term |
Granted publication date: 20110330 |
|
| CX01 | Expiry of patent term |