CN203233312U - Switch power supply controller and switch power supply device - Google Patents

Abstract

The utility model is suitable for the field of switch power supplies and provides a switch power supply controller which is connected with a power supply, a transformer and an isolation drive module. The isolation drive module receives a drive signal and outputs a feedback signal. The switch power supply controller comprises a feedback unit and an oscillating control unit. The feedback unit samples voltage and current output by the output side of a switch power supply, and the output end outputs the drive signal to the isolation drive module. The feedback end of the oscillating control unit is connected with the output end of the isolation drive module. The oscillating control unit controls disconnection of an energy storage circuit of the transformer according to the feedback signal or carries out energy storage and demagnetization at a predetermined frequency. The oscillating control unit controls disconnection and connection of the energy storage circuit of the primary side of the transformer according to the feedback signal, so that the switch power supply outputs constant current and constant voltage. By using the switch controller with high integration, constant voltage and constant current output of the switch power supply can be realized, and the volume of the switch power supply is reduced.

Description

A kind of switch power controller and switching power unit

Technical field

The utility model belongs to field of switch power, relates in particular to a kind of switch power controller and switching power unit.

Background technology

Along with the continuous development of switch power technology, the Switching Power Supply that more and more is tending towards miniaturization is applied to charger, adapter, LED(light-emitting diode, light-emitting diode more and more widely) in the electronic equipment such as driving power.

The Switching Power Supply of present middle low power mainly contains two kinds of topological structures: former limit feedback and secondary feedback.Wherein, the dynamic response of secondary feedback is fast, but need photoelectrical coupler, three ends are adjustable shunting a reference source (as: TL431) and more discrete component, circuit structure is complicated; Shunting a reference source that former limit feedback does not then need photoelectrical coupler, three ends are adjustable, circuit structure is simple relatively, but dynamic response is slow.

The utility model content

The purpose of the utility model embodiment is to provide a kind of switch power controller, is intended to solve traditional Switching Power Supply dynamic response and the contradictory problems between the circuit level.

The utility model embodiment realizes like this, a kind of switch power controller, be used for having the Switching Power Supply on input limit and output limit, be connected with power supply, the transformer with former limit and secondary and isolation drive module, described isolation drive module receives and drives the signal output feedback signal, and described switch power controller comprises:

Power end, earth terminal, voltage detecting end and current detecting end all are connected with the output limit of described Switching Power Supply, described feedback unit sample described Switching Power Supply the output limit electric current and voltage and at its output output drive signal to the feedback unit of described isolation drive module;

Input is connected with the positive pole of described power supply and the different name end on described former limit respectively with output, or its input is connected with the end of the same name on described former limit and the negative pole of power supply respectively with output, the feedback end of described oscillation control unit is connected with the output of described isolation drive module, described oscillation control unit control according to described feedback signal described transformer tank circuit disconnection or with predeterminated frequency energy storage and demagnetization, so that the oscillation control unit of described Switching Power Supply output constant voltage and constant current.

In a preferred embodiment, described switch power controller adopts the encapsulation of double-basis island, and described feedback unit is located at first Ji Dao, and described oscillation control unit is located at second Ji Dao.

In a preferred embodiment, described feedback unit comprises the output voltage judge module with described voltage detecting end, the output current judge module with described current detecting end and Digital Logic processing module;

Described output voltage judge module comprises first a reference source, the voltage detecting end of described output voltage judge module is connected with the output limit of described Switching Power Supply as the described voltage detecting end of described feedback unit, and the voltage of the described Switching Power Supply output of sampling and described first a reference source is back output voltage comparative result relatively;

Described output current judge module, comprise second a reference source, the current detecting end of described output current judge module is connected with the output limit of described Switching Power Supply as the described current detecting end of described feedback unit, and the electric current of the described Switching Power Supply output of sampling and described second a reference source is back output current comparative result relatively;

Described Digital Logic processing module receives and exports described driving signal according to described voltage comparative result and electric current comparative result at its output, and its output is as the described output of described feedback unit;

The power end of described output voltage judge module, output current judge module and Digital Logic processing module and earth terminal are respectively as described power end and the described earth terminal of described feedback unit.

In a preferred embodiment, described oscillation control unit comprises voltage controlled oscillator, power supply generation module and power switch;

The input of described power switch, output are successively as input, the output of described oscillation control unit;

The input of described power supply generation module is connected with the input of described power switch;

The feedback end of described voltage controlled oscillator as the feedback end of described oscillation control unit be connected with the output of described isolation drive module, power end and the output of described power supply generation module is connected, output outputs control signals to described power switch control end to be to control described power switch remain off or with the predeterminated frequency conducting with end, the earth terminal of the earth terminal of described voltage controlled oscillator, described power supply generation module and the output of described power switch are connected with the negative pole of power supply.

In a preferred embodiment, described output voltage judge module also comprises first comparator, the positive input terminal of described first comparator as described voltage detecting end be connected with the output limit of described Switching Power Supply, negative input end is connected with described first a reference source, output is connected with the first input end of described Digital Logic processing module.

In a preferred embodiment, described output current judge module comprises second comparator, first divider resistance and second divider resistance, the positive input terminal of described second comparator is connected with first output of described second a reference source, one end of first divider resistance is connected with the negative input end of described second comparator and is connected with second output of described second a reference source through described second divider resistance, the other end is connected with the output limit of described Switching Power Supply as described current detecting end, and the output of described second comparator is connected with second input of described Digital Logic processing module.

In a preferred embodiment, described digital signal processing module is or door, first input end, second input described or door are connected with the output of described first comparator, the output of described second comparator respectively, and output described or door is exported described driving signal.

In a preferred embodiment, described power supply generation module comprises diode D1 and storage capacitor C1, the anode of described diode D1 as the input of described power supply generation module be connected with the input of described power switch, negative electrode is connected with the power end of described voltage controlled oscillator as the output of described power supply generation module, the negative electrode of described diode D1 and be connected with the negative pole of described power supply through described storage capacitor C1;

Described power switch is the N-type metal-oxide-semiconductor, as input, output, the control end of described power switch, the drain electrode of N-type metal-oxide-semiconductor is connected with the positive pole of described power supply through described former limit successively for the drain electrode of described N-type metal-oxide-semiconductor, source electrode, grid, source electrode is connected with the negative pole of described power supply.

Above-mentioned switch power controller detects by feedback unit and drives isolation drive module output feedback signal according to the electric current and voltage output drive signal that transformer is exported, oscillation control unit is according to the disconnection of the tank circuit on the former limit of this feedback signal control transformer or with predeterminated frequency energy storage and demagnetization, to realize Switching Power Supply output constant current and constant voltage, so, use the high on-off controller of integrated level namely can realize the constant pressure and flow output of Switching Power Supply, reduced the volume of Switching Power Supply.

Another purpose of the utility model embodiment is to provide a kind of switching power unit, comprises transformer, isolation drive module and above-mentioned switch power controller with former limit and secondary, and described isolation drive module receives and drives the signal output feedback signal.

In a preferred embodiment, also comprise rectifier, filter capacitor C2, diode D2, sampling resistor R3, divider resistance R4, divider resistance R5 and filter capacitor C3, wherein,

Described isolation drive module is photoelectrical coupler, the first input end of described photoelectrical coupler is connected with the output of described feedback unit, the second input termination output signal ground, and first output of described photoelectrical coupler is connected with the feedback end of described oscillation control unit, second output is connected with the output of described oscillation control unit;

Two inputs of described rectifier are connected with two outputs of AC power respectively, the common cathode output of described rectifier is connected with the input of described oscillation control unit through described former limit, and the common anode output end of described rectifier is connected with the output of described vibration control module;

Described filter capacitor C2 is connected the common cathode output of described rectifier and is total between the anode output end;

The power end of described feedback unit is connected with the negative electrode of described diode D2, the anode of described diode D2 is connected with the end of the same name of described secondary, and the earth terminal of described feedback unit connects output signal ground;

The current detecting end of described feedback unit is connected with the different name end of described secondary and connects output signal ground through described sampling resistor R3;

Above-mentioned switch power controller detects by feedback unit and drives isolation drive module output feedback signal according to the electric current and voltage output drive signal that transformer is exported, oscillation control unit is according to the disconnection of the tank circuit on the former limit of this feedback signal control transformer or with predeterminated frequency energy storage and demagnetization, to realize Switching Power Supply output constant current and constant voltage, traditional approach has reduced discrete component relatively, make circuit structure become simple, dynamic response is fast, use the high on-off controller of integrated level namely can realize the constant pressure and flow output of Switching Power Supply simultaneously, dwindled the volume of Switching Power Supply.

Description of drawings

Fig. 1 is the module map of the switch power controller that provides of the utility model one embodiment;

Fig. 2 is the module map of the switch power controller that provides of another embodiment of the utility model;

Fig. 3 is the modular structure figure of the switch power controller that provides of the utility model one embodiment;

Fig. 4 is the schematic diagram of the switch power controller that provides of the utility model one embodiment;

Fig. 5 is the schematic diagram of the switching power unit that provides of the utility model one embodiment.

Embodiment

In order to make the technical problems to be solved in the utility model, technical scheme and beneficial effect clearer, below in conjunction with drawings and Examples, the utility model is further elaborated.Should be appreciated that specific embodiment described herein only in order to explaining the utility model, and be not used in restriction the utility model.

As illustrated in fig. 1 and 2, show the switch power controller module map that a preferred embodiment provides, for convenience of description, only show the part relevant with present embodiment.

A kind of switch power controller 100 is used for having the Switching Power Supply on input limit and output limit, and the input limit of Switching Power Supply and output limit generally demarcate as the border with the former limit of transformer and secondary.

Switch power controller 100 is connected with power supply 200, transformer T1 and isolation drive module 300, transformer T1 has former limit and secondary, isolation drive module 300 receives and drives the signal output feedback signal, and switch power controller 100 comprises feedback unit 100A and oscillation control unit 100B.

The power end 8 of feedback unit 100A, earth terminal 5, voltage detecting end 7 and current detecting end 6 all are connected with the output limit of Switching Power Supply, specifically be all to be electrically connected with the secondary of transformer T1, the electric current and voltage of the output limit output of feedback unit 100A sampling switch power supply (voltage of the secondary output of transformer T1 is through being the voltage of Switching Power Supply output behind the rectifying and wave-filtering), and at its output 4 output drive signals to isolation drive module 300, the earth terminal 5 of feedback unit 100A connects outside output signal ground.

The input 1 of oscillation control unit 100B and output 2 are connected (with reference to figure 1) with the end of the same name on the former limit of transformer T1 and the negative pole of power supply 200 respectively, or the input 1 of oscillation control unit 100B and output 2 are connected (with reference to figure 2) with the different name end on the former limit of the anodal transformer T1 of power supply 200 respectively.

The feedback end 3 of oscillation control unit 100B is connected with the output of isolation drive module 300, according to the disconnection of the tank circuit of feedback signal control transformer T1 or with predeterminated frequency energy storage and demagnetization, specifically be to utilize the power switch 106 of being located at oscillation control unit 100B to realize this function (with reference to figure 3,4), so that Switching Power Supply output constant voltage and constant current.

With reference to figure 3,4,5, in the present embodiment, the power end 8 of feedback unit 100A, voltage detecting end 7, current detecting end 6, output 4, earth terminal 5 successively as power supply input pin VO, the voltage detecting pin VR of switch power controller 100, current detecting pin IR, drive pin VC, output signal ground GND2; The input 1 of oscillation control unit 100B, output 2, feedback end 3 are successively as the control pin D of switch power controller 100, input ground GND1, feedback pin FB.

Above-mentioned switch power controller 100 detects by feedback unit 100A and drives isolation drive module 300 output feedback signals according to the electric current and voltage output drive signal that transformer T1 exports, oscillation control unit 100B is according to the disconnection of the tank circuit on the former limit of this feedback signal control transformer T1 or with predeterminated frequency energy storage and demagnetization, to realize Switching Power Supply output constant current and constant voltage, so, use the high on-off controller 100 of integrated level namely can realize the constant pressure and flow output of Switching Power Supply, reduced the volume of Switching Power Supply.

Therein among embodiment, switch power controller 100 adopts the DIP8(Double In-line Package on double-basis island, the dual inline type assembling) encapsulation, the 100A feedback unit is located at first Ji Dao, oscillation control unit 102B is located at second Ji Dao, thereby can guarantee the input and output electrical isolation.

As shown in Figure 3, show switch power controller 100 that a preferred embodiment provides modular structure figure more specifically, for convenience of description, only show the part relevant with present embodiment.

In a preferred embodiment, feedback unit 100A comprises output voltage judge module 101, output current judge module 102 and Digital Logic processing module 103, and output voltage judge module 101 has voltage detecting end 7, output current comparison module 102 has current detecting end 6.

Output voltage judge module 101 comprises first a reference source, the voltage detecting end 7 of output voltage judge module 101 is connected with the output limit of Switching Power Supply as the voltage detecting end 7 of feedback unit 100A, and the voltage of sampling switch power supply output and first a reference source is back output voltage comparative result VRC relatively; Output current judge module 102 comprises second a reference source, the current detecting end 7 of output current judge module 102 is connected with the output limit of Switching Power Supply as the current detecting end 7 of feedback unit 100A, specifically be to be electrically connected with the secondary of transformer T1, the electric current of sampling switch power supply output and second a reference source is back output current comparative result IRC relatively; Digital Logic processing module 103 receive and according to voltage comparative result and electric current comparative result at its output output drive signal, the output of Digital Logic processing module 103 is as the output 4 of feedback unit 100A, namely as the driving pin VC of switch power controller 100.

The power end of output voltage judge module 101, output current judge module 102 and Digital Logic processing module 103 and earth terminal are respectively as power end 8 and the earth terminal 5 of feedback unit 100A.

In a preferred embodiment, oscillation control unit 100B comprises power supply generation module 104, voltage controlled oscillator 105 and power switch 106.

The input of power supply generation module 104 is connected with the input of power switch 106; The input of power switch 106, output are successively as input 1, the output 2 of oscillation control unit 100B; The feedback end of voltage controlled oscillator 105 is connected with the output of isolation drive module 300 as the feedback end 3 of oscillation control unit 100B, the power end of voltage controlled oscillator 105 is connected with the output of voltage generating module 104, the control end that the output of voltage controlled oscillator 105 outputs control signals to power switch 106 is with control power switch remain off or with the predeterminated frequency conducting with end the earth terminal of voltage controlled oscillator 105, the output of the earth terminal of power supply generation module 104 and power switch 106 all is connected with the negative pole of power supply 200 as the input ground GND1 of switch power controller 100.

As shown in Figure 4, show the schematic diagram of the switch power controller 100 that a preferred embodiment provides, for convenience of description, only show the part relevant with present embodiment.

In a preferred embodiment, output voltage judge module 101 comprises first a reference source and the first comparator U1, the positive input terminal of the first comparator U1 is connected with the output limit of Switching Power Supply as the voltage detecting end 7 of feedback unit 100A, specifically be to be connected with the divider resistance output of output voltage, the negative input end of the first comparator U1 is connected with described first a reference source, the output of the first comparator U1 is connected with the first input end of Digital Logic processing module 103.

In a preferred embodiment, output current judge module 102 comprises second a reference source, the second comparator U2, the first divider resistance R1 and the second divider resistance R2, the positive input terminal of second comparator 102 is connected with first output of second a reference source, the end of the first divider resistance R1 is connected with the negative input end of the second comparator U2 and is connected with second output of second a reference source through the described second divider resistance R2, the other end of the first divider resistance R1 is connected with the output limit of Switching Power Supply as the current detecting end 6 of feedback unit 100A, specifically be to be connected with the different name end of transformer T1 secondary, the output of the second comparator U2 is connected with second input of Digital Logic processing module 103.

In a preferred embodiment, described digital signal processing module 103 is or door U3, or first input end, second input of door U3 be connected with the output of the first comparator U1, the output of the second comparator U2 respectively, or the output of U3 is exported described driving signal.

In a preferred embodiment, power supply generation module 104 comprises diode D1 and storage capacitor C1, the anode of diode D1 as the input of power supply generation module 104 be connected with the positive pole of power supply 200 with former limit through transformer T1, the negative electrode of diode D1 is connected with the power end of voltage controlled oscillator 105 as the output of power supply generation module 104, the negative electrode of diode D1 and be connected with the negative pole of power supply 200 through storage capacitor C1.

In a preferred embodiment, power switch 106 is N-type metal-oxide-semiconductor Q1, the drain electrode of N-type metal-oxide-semiconductor Q1, source electrode, grid be successively as input, output, the control end of power switch 106, and namely the drain electrode of N-type metal-oxide-semiconductor Q1, source electrode are successively as the input 1(control pin D of oscillation control unit 100B), output 2(input ground GND1).

The drain electrode of N-type metal-oxide-semiconductor Q1 is connected with the positive pole of power supply 200 through the former limit (namely being connected with the end of the same name on former limit) of transformer T1, the source electrode of N-type metal-oxide-semiconductor Q1 is connected with the negative pole of power supply 200; Or the drain electrode of N-type metal-oxide-semiconductor Q1 is connected with the positive pole of power supply 200, the source electrode of N-type metal-oxide-semiconductor Q1 is connected with the negative pole of power supply 200 with the former limit (namely being connected with the different name end on former limit) of transformer T1.

In addition, as shown in Figure 5, a kind of switching power unit also is provided, and switching power unit comprises transformer T1, isolation drive module 300 and the above-mentioned switch power controller 100 with former limit and secondary, and isolation drive module 300 receives and drives the signal output feedback signal.The structure of switch power controller 100 and the principle of work and power thereof repeat no more as mentioned above here.

In the present embodiment, isolation drive module 200 is photoelectrical coupler, the driving pin VC of the first input end of photoelectrical coupler G1 and the output 4(switch power controller 100 of feedback unit 100A) is connected, the second input termination output signal ground (being the earth terminal 5 of above-mentioned feedback unit or the output signal ground GND2 of controller), the feedback pin FB of first output of photoelectrical coupler G1 and the feedback end 3(switch power controller 100 of oscillation control unit 100B) be connected, the input ground GND1 of second output and the output 2(switch power controller 100 of oscillation control unit 100B) is connected.Photoelectrical coupler G1 realizes the mirror image of electric current, and it mainly acts on is the isolation that realizes output signal ground GND2 with the input ground GND1 of switch power controller 100, guarantees the isolation safe output of Switching Power Supply.

Therein among embodiment, if when power supply is D.C. regulated power supply, switching power unit also comprises diode D2, sampling resistor R3, divider resistance R4, divider resistance R5 and filter capacitor C3.

The power end 8 of feedback unit 100A is connected with the negative electrode of described diode D2, the anode of described diode D2 is connected with the end of the same name of the secondary of transformer T1; The current detecting end 6 of feedback unit 100A is connected with the different name end of the secondary of transformer T1 and connects output signal ground through sampling resistor R3; The voltage detecting end 7 of feedback unit 100A be connected with the negative electrode of diode D2 through divider resistance R4 and connect output signal ground through divider resistance R5; Filter capacitor C3 one end is connected with negative electrode and the load 100 of described diode D2, another termination output signal ground of filter capacitor C3, and the earth terminal 5 of feedback unit 100A connects outside output signal ground as the output signal ground GND2 end of switch power controller 100.

Among embodiment, switching power unit also comprises rectifier BR1, filter capacitor C2 therein.

Two inputs of rectifier BR1 are connected with two outputs of AC power AC respectively, the common cathode output of rectifier BR1 is connected with the input 1 of oscillation control unit 100B through the former limit of transformer T1, and the common anode output end of rectifier BR1 is connected with the output 2 of vibration control module 100B; Filter capacitor C1 is connected the common cathode output of rectifier BR1 and is total between the anode output end.

Be the operation principle of example explanation switch power controller 100 with an embodiment below, in conjunction with Fig. 4,5.

Suppose when the output control signal VG of voltage controlled oscillator 105 is high level, power switch 106 conductings, when control signal VG was low level, power switch 106 was by (also claiming to close).

At the beginning of Switching Power Supply powered on, power switch 106 ended, and the voltage VD of the input 1 of oscillation control unit 100B gives storage capacitor C1 charging through diode D1 after the rectifier BR1 rectification, produces supply voltage VDD.Because supply voltage VDD only provides the power supply of voltage controlled oscillator 105, so need very little drive current, the appearance value of storage capacitor C1 only is the pF magnitude, can be integrated in the inside of switch power controller 100, does not need outside discrete capacitor element.

Because at the beginning of power-supply system powers on, output voltage is 0V voltage, so output voltage judge module 101, the power end of output current judge module 102 and Digital Logic processing module 103 all with power end 8(power supply input pin VO) be 0 volt (also claiming low level), so the driving signal of Digital Logic processing module 103 outputs is low levels, drive pin VC and connect photoelectrical coupler G1, the input no current of photoelectrical coupler G1 flows into, so feedback pin FB does not have pull-down current, feedback pin FB end keeps original high level state, the voltage controlled oscillator 105 normal higher-orders of oscillation (as the 65KHz vibration) output, along with the high frequency conducting of power switch 106 with close, transformer T1 transfers energy to the output of Switching Power Supply, and output voltage V out raises gradually.When output voltage V out reaches certain voltage (as 3V), output voltage judge module 101, output current judge module 102 and Digital Logic processing module 103 beginning operate as normal.

Constant current work: (the constant voltage voltage of general electronic equipment is all greater than 5V before the output voltage V out of Switching Power Supply reaches default constant voltage voltage Vcv, the switch power controller 100 that the utility model provides is applicable to that constant voltage voltage Vcv is higher than the normal working voltage of output voltage judge module 101, output current judge module 102 and Digital Logic processing module 103), namely the voltage of process divider resistance R4, the acquisition of divider resistance R5 dividing potential drop is less than the voltage Vr1 of first reference circuit generation, and therefore the output signal VRC of the first comparator U1 is low level; The output of output voltage judge module 101 can occlusion pressure controlled oscillator 105, and the state of power switch 106 depends on the output signal IRC of output current comparison module 102.

When output current Iout reaches default continuous current Icc, the output signal IRC of the second comparator U2 is high level, driving signal through 103 outputs of Digital Logic processing module still is high level, drive signal and be input to photoelectrical coupler G1, because photoelectrical coupler G1 has electric current to flow through, photoelectrical coupler G1 drags down the level of feedback pin FB, occlusion pressure controlled oscillator 105, thus close power switch pipe 106.This moment system by the alternate conduction of the control remain off of power switch pipe or high frequency with by maintaining the constant current operating state.

Constant current state is, supposes that the voltage of current detecting pin IR is Vir, and when electric current flow through, with respect to output signal ground GND2, Vir was negative value, and when electric current is more big, negative value is more big.

Through the conducting of power switch 105 and by control, during constant current state,

Vr3＝Vr4

Through the dividing potential drop formula as can be known,

$\mathrm{<figure-callout\; id="3"\; label="Vr"\; filenames="HDA00003105505800011.png,HDA00003105505800012.png"\; state="\{\{state\}\}">Vr</figure-callout>}3=\mathrm{Vir}+\frac{(\mathrm{Vr}2-\mathrm{Vir})}{\mathrm{<figure-callout\; id="1"\; label="R"\; filenames="HDA00003105505800011.png,HDA00003105505800012.png"\; state="\{\{state\}\}">R</figure-callout>}1+\mathrm{<figure-callout\; id="2"\; label="R"\; filenames="HDA00003105505800011.png,HDA00003105505800012.png"\; state="\{\{state\}\}">R</figure-callout>}2}\&CenterDot;\mathrm{<figure-callout\; id="2"\; label="R"\; filenames="HDA00003105505800011.png,HDA00003105505800012.png"\; state="\{\{state\}\}">R</figure-callout>}2$

So, the voltage Vir of current detecting pin IR end is,

$\mathrm{Vir}=\frac{\mathrm{<figure-callout\; id="4"\; label="Vr"\; filenames="HDA00003105505800011.png,HDA00003105505800012.png"\; state="\{\{state\}\}">Vr</figure-callout>}4\&CenterDot;(\mathrm{<figure-callout\; id="1"\; label="R"\; filenames="HDA00003105505800011.png,HDA00003105505800012.png"\; state="\{\{state\}\}">R</figure-callout>}1+R2)-\mathrm{<figure-callout\; id="2"\; label="Vr"\; filenames="HDA00003105505800011.png,HDA00003105505800012.png"\; state="\{\{state\}\}">Vr</figure-callout>}2\&CenterDot;R2}{\mathrm{<figure-callout\; id="1"\; label="R"\; filenames="HDA00003105505800011.png,HDA00003105505800012.png"\; state="\{\{state\}\}">R</figure-callout>}1}$

Constant Electric Current flow valuve Icc is,

$\mathrm{Icc}=-\frac{\mathrm{<figure-callout\; id="3"\; label="Vir\; R"\; filenames="HDA00003105505800011.png,HDA00003105505800012.png"\; state="\{\{state\}\}">Vir</figure-callout>}}{R}=\frac{-\mathrm{<figure-callout\; id="4"\; label="Vr"\; filenames="HDA00003105505800011.png,HDA00003105505800012.png"\; state="\{\{state\}\}">Vr</figure-callout>}4\&CenterDot;(\mathrm{<figure-callout\; id="1"\; label="R"\; filenames="HDA00003105505800011.png,HDA00003105505800012.png"\; state="\{\{state\}\}">R</figure-callout>}1+R2)+\mathrm{<figure-callout\; id="2"\; label="Vr"\; filenames="HDA00003105505800011.png,HDA00003105505800012.png"\; state="\{\{state\}\}">Vr</figure-callout>}2\&CenterDot;R2}{\mathrm{<figure-callout\; id="1"\; label="R"\; filenames="HDA00003105505800011.png,HDA00003105505800012.png"\; state="\{\{state\}\}">R</figure-callout>}1\&CenterDot;\mathrm{<figure-callout\; id="3"\; label="R"\; filenames="HDA00003105505800011.png,HDA00003105505800012.png"\; state="\{\{state\}\}">R</figure-callout>}3}$

Constant voltage operating state: as output current Iout during less than default continuous current Icc, the output signal IRC of the second comparator U2 is low level, the output signal IRC of output current judge module 102 can occlusion pressure controlled oscillator 105, and the state of power switch 106 depends on the output signal VRC of output voltage judge module 101 modules.

As the output voltage V out of Switching Power Supply during greater than default constant voltage voltage Vcv, the output signal VRC of the first comparator U1 is high level, driving signal through 103 outputs of Digital Logic processing module still is high level, drive signal and be input to photoelectrical coupler G1, because photoelectrical coupler G1 has electric current to flow through, photoelectrical coupler G1 drags down the level of feedback pin FB, occlusion pressure controlled oscillator 105, thus close power switch 106.As the output voltage V out of Switching Power Supply during less than default constant voltage voltage Vcv, operation principle is the same.System through the alternate conduction of the control remain off of power switch 106 or high frequency with by maintaining the constant voltage operating state.

During pressure constant state, the voltage of supposing voltage detecting pin VR is VR, and the voltage Vr1 of VR and first a reference source output equates, again by the dividing potential drop formula as can be known,

$\mathrm{VR}=\frac{\mathrm{Vout}\&CenterDot;R5}{\mathrm{<figure-callout\; id="4"\; label="R"\; filenames="HDA00003105505800011.png,HDA00003105505800012.png"\; state="\{\{state\}\}">R</figure-callout>}4+\mathrm{<figure-callout\; id="5"\; label="R"\; filenames="HDA00003105505800021.png,HDA00003105505800041.png"\; state="\{\{state\}\}">R</figure-callout>}5}$

The Vout of this moment is constant voltage value Vcv,

$\mathrm{Vcv}=\frac{\mathrm{VR}\&CenterDot;(\mathrm{<figure-callout\; id="5"\; label="R"\; filenames="HDA00003105505800021.png,HDA00003105505800041.png"\; state="\{\{state\}\}">R</figure-callout>}5+R4)}{\mathrm{<figure-callout\; id="5"\; label="R"\; filenames="HDA00003105505800021.png,HDA00003105505800041.png"\; state="\{\{state\}\}">R</figure-callout>}5}$

Switching Power Supply is operated in constant voltage or constant current mode, depend on fully with load 400, according to the situation of load, feedack control power switch 106 makes system stability in constant voltage or constant current state.

The utility model provides a kind of controller 100 of constant pressure and flow Switching Power Supply, since there are input ground GND1 and output signal ground GND2, thus the DIP8 encapsulation on double-basis island can be adopted, when can guarantee the input and output electrical isolation, improve the integrated level of controller, dwindled volume.

A kind of constant pressure and flow switching power unit that the utility model provides, need not starting resistance, need not auxiliary winding, need not the adjustable shunting a reference source elements such as (as: TL431) of three ends, circuit is simple, and discrete component is few, being easy to miniaturization uses, PCB(Printed circuit board, printed circuit board (PCB)) connect up easily the integrated level height, reduced the cost of system, dynamic response is fast, has improved stability and the reliability of system, meets the prior art development trend.

The above only is preferred embodiment of the present utility model; not in order to limit the utility model; all any modifications of within spirit of the present utility model and principle, doing, be equal to and replace and improvement etc., all should be included within the protection range of the present utility model.

Claims (10)

1. switch power controller, be used for having the switching power unit on input limit and output limit, be connected with power supply, the transformer with former limit and secondary and isolation drive module, described isolation drive module receives and drives the signal output feedback signal, it is characterized in that described switch power controller comprises:

Power end, earth terminal, voltage detecting end and current detecting end all are connected with the output limit of described Switching Power Supply, described feedback unit sample described Switching Power Supply the output limit electric current and voltage and at its output output drive signal to the feedback unit of described isolation drive module;

Input is connected with the positive pole of described power supply and the different name end on described former limit respectively with output, or its input is connected with the end of the same name on described former limit and the negative pole of power supply respectively with output, the feedback end of described oscillation control unit is connected with the output of described isolation drive module, described oscillation control unit control according to described feedback signal described transformer tank circuit disconnection or with predeterminated frequency energy storage and demagnetization, so that the oscillation control unit of described Switching Power Supply output constant voltage and constant current.

2. switch power controller as claimed in claim 1 is characterized in that, described switch power controller adopts the encapsulation of double-basis island, and described feedback unit is located at first Ji Dao, and described oscillation control unit is located at second Ji Dao.

3. switch power controller as claimed in claim 1 is characterized in that, described feedback unit comprises the output voltage judge module with described voltage detecting end, the output current judge module with described current detecting end and Digital Logic processing module;

Described output voltage judge module comprises first a reference source, the voltage detecting end of described output voltage judge module is connected with the output limit of described Switching Power Supply as the described voltage detecting end of described feedback unit, and the voltage of the described Switching Power Supply output of sampling and described first a reference source is back output voltage comparative result relatively;

Described output current judge module, comprise second a reference source, the current detecting end of described output current judge module is connected with the output limit of described Switching Power Supply as the described current detecting end of described feedback unit, and the electric current of the described Switching Power Supply output of sampling and described second a reference source is back output current comparative result relatively;

Described Digital Logic processing module receives and exports described driving signal according to described voltage comparative result and electric current comparative result at its output, and its output is as the described output of described feedback unit;

The power end of described output voltage judge module, output current judge module and Digital Logic processing module and earth terminal are respectively as described power end and the described earth terminal of described feedback unit.

4. as claim 1 or 3 described switch power controllers, it is characterized in that described oscillation control unit comprises voltage controlled oscillator, power supply generation module and power switch;

The input of described power switch, output are successively as input, the output of described oscillation control unit;

The input of described power supply generation module is connected with the input of described power switch;

The feedback end of described voltage controlled oscillator as the feedback end of described oscillation control unit be connected with the output of described isolation drive module, power end and the output of described power supply generation module is connected, output outputs control signals to described power switch control end to be to control described power switch remain off or with the predeterminated frequency conducting with end, the earth terminal of the earth terminal of described voltage controlled oscillator, described power supply generation module and the output of described power switch are connected with the negative pole of power supply.

5. switch power controller as claimed in claim 3, it is characterized in that, described output voltage judge module also comprises first comparator, the positive input terminal of described first comparator as described voltage detecting end be connected with the output limit of described Switching Power Supply, negative input end is connected with described first a reference source, output is connected with the first input end of described Digital Logic processing module.

6. as claim 3 or 5 described switch power controllers, it is characterized in that, described output current judge module comprises second comparator, first divider resistance and second divider resistance, the positive input terminal of described second comparator is connected with first output of described second a reference source, one end of first divider resistance is connected with the negative input end of described second comparator and is connected with second output of described second a reference source through described second divider resistance, the other end is connected with the output limit of described Switching Power Supply as described current detecting end, and the output of described second comparator is connected with second input of described Digital Logic processing module.

7. switch power controller as claimed in claim 5, it is characterized in that, described digital signal processing module is or door, first input end, second input described or door are connected with the output of described first comparator, the output of described second comparator respectively, and output described or door is exported described driving signal.

8. switch power controller as claimed in claim 4, it is characterized in that, described power supply generation module comprises diode D1 and storage capacitor C1, the anode of described diode D1 as the input of described power supply generation module be connected with the input of described power switch, negative electrode is connected with the power end of described voltage controlled oscillator as the output of described power supply generation module, the negative electrode of described diode D1 and be connected with the negative pole of described power supply through described storage capacitor C1;

Described power switch is the N-type metal-oxide-semiconductor, as input, output, the control end of described power switch, the drain electrode of N-type metal-oxide-semiconductor is connected with the positive pole of described power supply through described former limit successively for the drain electrode of described N-type metal-oxide-semiconductor, source electrode, grid, source electrode is connected with the negative pole of described power supply.

9. a switching power unit is characterized in that, comprises transformer with former limit and secondary, isolation drive module and as each described switch power controller of claim 1 to 8, described isolation drive module receives and drives the signal output feedback signal.

10. switching power unit as claimed in claim 9 is characterized in that, also comprises rectifier, filter capacitor C2, diode D2, sampling resistor R3, divider resistance R4, divider resistance R5 and filter capacitor C3, wherein,

Described isolation drive module is photoelectrical coupler, the first input end of described photoelectrical coupler is connected with the output of described feedback unit, the second input termination output signal ground, and first output of described photoelectrical coupler is connected with the feedback end of described oscillation control unit, second output is connected with the output of described oscillation control unit;

Two inputs of described rectifier are connected with two outputs of AC power respectively, the common cathode output of described rectifier is connected with the input of described oscillation control unit through described former limit, and the common anode output end of described rectifier is connected with the output of described vibration control module;

Described filter capacitor C2 is connected the common cathode output of described rectifier and is total between the anode output end;

The power end of described feedback unit is connected with the negative electrode of described diode D2, the anode of described diode D2 is connected with the end of the same name of described secondary, and the earth terminal of described feedback unit connects output signal ground;

The current detecting end of described feedback unit is connected with the different name end of described secondary and connects output signal ground through described sampling resistor R3;

The voltage detecting end of described feedback unit be connected with the negative electrode of described diode D2 through described divider resistance R4 and connect output signal ground through described divider resistance R5;

Described filter capacitor C3 one end is connected with negative electrode and the load of described diode D2, another termination output signal ground.

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