CN208367565U - Frequency compensation circuit and frequency control circuit - Google Patents
Frequency compensation circuit and frequency control circuit Download PDFInfo
- Publication number
- CN208367565U CN208367565U CN201820902869.9U CN201820902869U CN208367565U CN 208367565 U CN208367565 U CN 208367565U CN 201820902869 U CN201820902869 U CN 201820902869U CN 208367565 U CN208367565 U CN 208367565U
- Authority
- CN
- China
- Prior art keywords
- frequency
- circuit
- resistance
- nmos tube
- capacitor
- 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.)
- Active
Links
- 238000005070 sampling Methods 0.000 claims abstract description 29
- 239000003990 capacitor Substances 0.000 claims description 51
- 230000005611 electricity Effects 0.000 claims description 13
- 230000015556 catabolic process Effects 0.000 description 5
- 238000010586 diagram Methods 0.000 description 5
- 230000005669 field effect Effects 0.000 description 5
- 230000008859 change Effects 0.000 description 4
- 230000004044 response Effects 0.000 description 4
- 239000004065 semiconductor Substances 0.000 description 4
- KCXVZYZYPLLWCC-UHFFFAOYSA-N EDTA Chemical compound OC(=O)CN(CC(O)=O)CCN(CC(O)=O)CC(O)=O KCXVZYZYPLLWCC-UHFFFAOYSA-N 0.000 description 3
- 229960001484 edetic acid Drugs 0.000 description 3
- 230000009286 beneficial effect Effects 0.000 description 2
- 238000001914 filtration Methods 0.000 description 2
- 229910044991 metal oxide Inorganic materials 0.000 description 2
- 150000004706 metal oxides Chemical class 0.000 description 2
- 230000000087 stabilizing effect Effects 0.000 description 2
- 230000009471 action Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000005284 excitation Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000010349 pulsation Effects 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 239000002210 silicon-based material Substances 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000003381 stabilizer Substances 0.000 description 1
- 238000000108 ultra-filtration Methods 0.000 description 1
Landscapes
- Electronic Switches (AREA)
Abstract
The utility model relates to a frequency compensation circuit and frequency control circuit, frequency compensation circuit includes: the device comprises a voltage sampling circuit, a switching unit and a frequency compensation unit; the first end of the voltage sampling circuit is used for inputting a voltage signal, and the second end of the voltage sampling circuit is connected with the first end of the frequency compensation unit through the switch unit; the second end of the frequency compensation unit is used for connecting a frequency setting circuit; the switch unit is used for being turned on or turned off according to the voltage signal, and the frequency compensation unit is used for outputting a corresponding frequency compensation signal to the frequency setting circuit when the switch unit is turned on or turned off. By the frequency compensation circuit, the output frequency value can be changed through the input voltage signal, so that the switching frequency of the circuit is changed, and the loss of a circuit device is reduced. In addition, the use is convenient, and the operation is simple.
Description
Technical field
The utility model relates to compensation circuit technical fields, more particularly to a kind of frequency compensated circuit and a kind of frequency control
Circuit processed.
Background technique
There are a phenomenons for some topological structure circuits (such as circuit of reversed excitation, single- stage PFC circuit etc.): when circuit is non-solid
Determine turn-on time mode and under identical loading condition, circuit turn-on time increases with the reduction of input voltage, that is, is connected
Time is inversely proportional with input voltage, so as to cause circuit switch frequency height, the switching frequency when inputting high pressure when inputting low pressure
It is low.It due to input voltage and the unmatched problem of output frequency, is usually easy that circuit devcie is caused to be lost, such as low inputting
Peak primary voltage is big when pressure, be easy to cause core saturation, transformer heating;When inputting high pressure, it is easy to cause switching device
Loss.
Utility model content
Based on this, it is necessary to be easy to cause electricity for existing topological structure circuit input voltage and output frequency mismatch
The problem of path loss is hurt provides a kind of frequency compensated circuit.
A kind of frequency compensated circuit, comprising: voltage sampling circuit, switch unit and frequency compensation unit;
The first end of the voltage sampling circuit is used for input voltage signal, and the second end of the voltage sampling circuit passes through
The switch unit connects the first end of the frequency compensation unit;The second end of the frequency compensation unit is used for rate of connections
Initialization circuit;
For being opened or closed according to the voltage signal, the frequency compensation unit is used for described the switch unit
Corresponding frequency compensation signal is exported when switch unit opens or closes to the frequency setting circuit.
Above-mentioned frequency compensated circuit, including voltage sampling circuit, switch unit and frequency compensation unit, wherein voltage is adopted
The first end of sample circuit is used for input voltage signal, and the second end of voltage sampling circuit is single by the compensation of switch unit rate of connections
The first end of member;The second end of frequency compensation unit is used for rate of connections initialization circuit;Switch unit is used for according to voltage signal
It opens or closes, frequency compensation unit is for exporting corresponding frequency compensation signal when switch unit opens or closes to frequency
Initialization circuit.By above-mentioned frequency compensated circuit, output frequency value can be changed by the voltage signal of input, to come
The switching frequency for changing circuit, reduces the loss to circuit devcie.In addition, it is easy to use, it is easy to operate.
The voltage sampling circuit includes first resistor, first capacitor and second resistance in one of the embodiments,;Institute
The first end for stating first resistor connects the voltage input end, and the second end of the first resistor connects the switch unit;Institute
The first end of the first end and the second resistance of stating first capacitor is separately connected the switch unit, and the of the first capacitor
The second end of two ends and the second resistance is grounded respectively.
The voltage sampling circuit in one of the embodiments, further include: 3rd resistor;The second of the first resistor
End connects the switch unit by the 3rd resistor.
The switch unit includes the first NMOS tube in one of the embodiments,;The grid of first NMOS tube point
Do not connect the first end of the second end of the 3rd resistor, the first end of the first capacitor and the second resistance, described
The first end that the drain electrode of one NMOS tube connects the frequency compensation unit connects the drain electrode of first NMOS tube, and described first
The source electrode of NMOS tube is grounded.
The switch unit includes NPN type triode in one of the embodiments,;The base stage of the NPN type triode
It is separately connected the first end of the second end of the 3rd resistor, the first end of the first capacitor and the second resistance, it is described
The collector of NPN type triode connects the first end of the frequency compensation unit, the emitter grounding of the NPN type triode.
The frequency compensation unit includes the second capacitor in one of the embodiments,;The first end of second capacitor
The drain electrode of the first NMOS is connected, the second end of second capacitor connects the compensation making circuit.
According to above-mentioned frequency compensated circuit, a kind of frequency control circuit is additionally provided in the utility model embodiment.
A kind of frequency control circuit, including frequency setting circuit and the frequency compensated circuit, wherein the frequency is set
Determine circuit to include low level holding circuit and switch off control circuit;The first end of the low level holding circuit and shutdown control
The first end of circuit processed is separately connected the second end of the frequency compensation unit;The second end of the low level holding circuit is used for
The driving pin of PWM chip is connected, the measure voltage & current that the second end to switch off control circuit is used to connect PWM chip draws
Foot;
The low level holding circuit is used to export low level according to the frequency compensation signal and hold time to the pass
Disconnected control circuit, it is described to switch off control circuit for being held time control circuit switching frequency according to the low level.
Above-mentioned frequency control circuit is due to using above-mentioned frequency compensated circuit, so, it may have frequency compensation electricity
The corresponding beneficial effect in road, it can output frequency value is changed by the voltage signal of input, thus to change opening for circuit
Frequency is closed, the loss to circuit devcie is reduced.In addition, it is easy to use, it is easy to operate.
In one of the embodiments, the low level holding circuit include the 4th resistance, the 5th resistance, the 6th resistance and
Second NMOS tube;
The first end of 4th resistance connects the grid of second NMOS tube, and passes through the 5th resistance eutral grounding,
The second end of 4th resistance is used to connect the driving pin of the PWM chip;
The first end of 6th resistance connects the drain electrode of second NMOS tube, the second end connection of the 6th resistance
The second end of the frequency compensation unit;The source electrode of second NMOS tube is grounded.
It is described in one of the embodiments, to switch off control circuit including third capacitor, the 4th capacitor, diode, the 7th
Resistance, the 8th resistance and third NMOS tube;
The first end of the third capacitor connects the second end of the frequency compensation unit, the second end of the third capacitor
Ground connection;
4th capacitor and the 7th resistance are connected between the grid and source electrode of the third NMOS tube, and
The source electrode of the third NMOS tube is grounded, and the measure voltage & current that the drain electrode of the third NMOS tube connects the PWM chip draws
Foot;
The anode of the diode connects the grid of the third NMOS tube, and the cathode of the diode is separately connected described
The first end of the second end of frequency compensation unit and the 8th resistance, the second end external power supply of the 8th resistance.
The diode is Schottky diode in one of the embodiments,.
Detailed description of the invention
Fig. 1 is the structural schematic diagram of frequency compensated circuit in one embodiment;
Fig. 2 is the structural schematic diagram of frequency compensated circuit in one embodiment;
Fig. 3 is the structural schematic diagram of frequency control circuit in one embodiment;
Fig. 4 is the structural schematic diagram of frequency control circuit in one embodiment;
Fig. 5 is the operating voltage waveform configuration schematic diagram of frequency control circuit in one embodiment.
Specific embodiment
The content of the utility model is described in further detail below in conjunction with preferred embodiment and attached drawing.Obviously, under
Literary described embodiment only explains the utility model, rather than the restriction to the utility model.Based on the reality in the utility model
Example is applied, every other embodiment obtained by those of ordinary skill in the art without making creative efforts all belongs to
In the range of the utility model protection.It should be noted that illustrating only for ease of description, in attached drawing and the utility model phase
The part of pass rather than full content.
For the ease of understanding the utility model, below with reference to relevant drawings to being originally described more fully.It needs
Bright, when an element is considered as " connection " another element, it can be directly to another element and therewith
It is combined as a whole, or may be simultaneously present centering elements.Term as used herein " installation ", " one end ", " other end " with
And similar statement is for illustrative purposes only.
Unless otherwise defined, all technical and scientific terms used herein and the technology people for belonging to the art
The normally understood meaning of member is identical.Term used in book described herein is intended merely to the mesh of description specific embodiment
, it is not intended that in limitation the utility model.Term " and or " used herein includes one or more relevant institute's lists
Any and all combinations of purpose.In addition, " first ", " second ", " third ", " the 4th " are intended merely to distinguish and are retouched herein
The object stated not is the restriction to object.
A kind of frequency compensated circuit, as shown in Figure 1, comprising: voltage sampling circuit 10, switch unit 20 and frequency compensation list
Member 30;The first end (VG as shown in figure 1) of voltage sampling circuit 10 be used for input voltage signal, the second of voltage sampling circuit 10
End passes through the first end of 20 rate of connections compensating unit 30 of switch unit;The second end of frequency compensation unit 30 is (as shown in figure 1
TOFF) it is used for rate of connections initialization circuit 200;Switch unit 20 according to voltage signal for opening or closing, frequency compensation list
Member 30 is for exporting corresponding frequency compensation signal when switch unit opens or closes to frequency setting circuit 200.
Specifically, VG is used for input voltage signal, and voltage signal is usually the voltage signal behind commercial power rectification, that is, is usually
Voltage after 90-264VAC rectification, waveform are the DC voltage of pulsation, referred to as steamed bun wave.It is defeated that voltage sampling circuit 10 receives VG
The voltage signal entered, and voltage signal is sent to switch unit 20, switch unit 20 is opened or closed according to voltage signal (leads
Logical or cut-off), frequency compensation unit 30 exports corresponding frequency compensation signal to frequency when switch unit 20 opens or closes
Initialization circuit 200.Under normal conditions, when switch unit is opened, frequency compensated circuit is connected with frequency setting circuit, i.e., will mend
Unit 30 is repaid to be connected in frequency compensated circuit 200;When switch unit is closed, frequency compensated circuit and frequency setting circuit are disconnected
It opens, i.e., compensating unit 30 is disconnected with frequency compensated circuit 200, by accessing or not accessing frequency setting electricity for compensating unit
Road carries out frequency compensation to circuit to realize the frequency compensation signal to provide different.
Above-mentioned frequency compensated circuit, including voltage sampling circuit 10, switch unit 20 and frequency compensation unit 30, wherein
The first end of voltage sampling circuit 10 is used for input voltage signal, and the second end of voltage sampling circuit 10 is connected by switch unit 20
Connect the first end of frequency compensation unit 30;The second end of frequency compensation unit 30 is used for rate of connections initialization circuit 200;Switch is single
For member 20 for being opened or closed according to voltage signal, frequency compensation unit 30 is used for the output phase when switch unit opens or closes
The frequency compensation signal answered is to frequency setting circuit 200.By above-mentioned frequency compensated circuit, can be believed by the voltage of input
Number change output frequency value, to reduce the loss to circuit devcie to change the switching frequency of circuit.In addition, using
It is convenient, it is easy to operate.
In one of the embodiments, as shown in Fig. 2, voltage sampling circuit 10 includes first resistor R1, first capacitor C1
With second resistance R2;The first end of first resistor R1 is used for input voltage signal, the second end connection switch list of first resistor R1
Member 20;The first end of first capacitor C1 and the first end of second resistance R1 are separately connected switch unit 20, and the of first capacitor C1
The second end of two ends and second resistance R2 are grounded respectively.
Specifically, voltage sampling circuit 10 includes first resistor R1, first capacitor C1 and second resistance R2;Wherein, it switchs
The first end of unit 20 is used for input voltage signal by first resistor R1, and passes through first capacitor C1 and second resistance R2 respectively
The second end of ground connection, switch unit 20 passes through 30 rate of connections frequency compensated circuit 200 of frequency compensation unit.In the present embodiment
In, first capacitor C1 is mainly used for filtering, the voltage signal of removal voltage input end input is used for smooth voltage signal.The
Two resistance R2 reduce the excessively high damage to switch unit 20 of voltage signal of input for dividing mainly as divider resistance.
In one of the embodiments, as shown in Fig. 2, voltage sampling circuit further includes 3rd resistor R3;First resistor R1
Second end pass through 3rd resistor R3 connection switch unit 20.
Specifically, voltage sampling circuit 20 further includes 3rd resistor R3, and wherein 3rd resistor R3 is connected to first resistor R1
Between switch unit 20,3rd resistor R3 is mainly used for dividing, and the voltage signal for being further reduced input is excessively high single to switch
The damage of member 20.
In one of the embodiments, as shown in Fig. 2, switch unit 20 includes the first NMOS tube Q1;First NMOS tube Q1
Grid be separately connected the first end of the second end of 3rd resistor R3, the first end of first capacitor C1 and second resistance R2, first
The first end of the drain electrode rate of connections compensating unit 30 of NMOS tube Q1, the source electrode ground connection of the first NMOS tube Q1.
Specifically, metal-oxide-semiconductor (Metal-Oxide-Semiconductor Field-Effect Transistor, metal-
Oxide semiconductor field effect transistor), abbreviation metal-oxide half field effect transistor, be one kind can be widely used in analog circuit with
The field-effect transistor (field-effect transistor) of digital circuit.MOS according to its " channel " (work carrier) pole
Property it is different, the two types of " N-type " Yu " p-type ", also commonly known as NMOS tube and PMOS tube can be divided into.NMOS tube and PMOS tube are all
It is common transistor, it is very easy to use.In the present embodiment, voltage sample is worked as switch unit using NMOS tube Q1
The voltage signal that circuit 10 receives voltage input end VG input is that (i.e. voltage sampling circuit 10 is to the first NMOS for high voltage signal
The grid of pipe Q1 applies high level) when, the source electrode and drain electrode conducting of the first NMOS tube, to make frequency compensation unit 30 according to electricity
The voltage signal of input terminal VG input is pressed to export corresponding output frequency value.Using NMOS tube, easy to use and power consumption is very low.
Switch unit 20 includes NPN type triode in one of the embodiments,;The base stage of NPN type triode connects respectively
Connect the first end of the second end of 3rd resistor, the first end of first capacitor and second resistance, the collector connection of NPN type triode
The first end of frequency compensation unit, the emitter grounding of NPN type triode.
Specifically, triode, full name should be transistor, also referred to as bipolar junction transistor, transistor, be electronics
Most important device in circuit mainly plays Current amplifier and on-off action.Triode be broadly divided into two class PNP type triodes and
NPN type triode.In the present embodiment, using NPN type triode as switch unit, when voltage sampling circuit 10 receives electricity
The voltage signal for pressing input terminal VG input is that (i.e. voltage sampling circuit 10 applies high voltage signal to the base stage of NPN type triode
High level) when, collector and the emitter-base bandgap grading conducting of NPN type triode, to make frequency compensation unit 30 according to voltage input end VG
The voltage signal of input exports corresponding output frequency value.Using NPN type triode, easy to use and power consumption is very low.
In one of the embodiments, as shown in Fig. 2, frequency compensation unit 30 includes the second capacitor C2;Work as switch unit
10 when being the first NMOS tube, and the first end of the second capacitor C2 connects the drain electrode of the first NMOS tube Q1, the second end of the second capacitor C2
Rate of connections initialization circuit 200.
When switch unit 10 is NPN type triode, the current collection of the first end connection NPN type triode of the second capacitor C2
Pole, the second end rate of connections initialization circuit 200 of the second capacitor C2.
Specifically, capacitor is that one of the electronic component largely used in electronic equipment is widely used in circuit, is had
Separated by direct communication, coupling, bypass, filtering, resonant tank, energy conversion and control etc..In the present embodiment, capacitor is utilized
Charge and discharge electro ultrafiltration using capacitor as frequency compensated circuit, thus to circuit carry out frequency compensation.The simple and side using capacitor
Just.
According to above-mentioned frequency compensated circuit, a kind of frequency control circuit is additionally provided in the utility model embodiment.
A kind of frequency control circuit, as shown in figure 3, including frequency compensation described in frequency setting circuit and any embodiment
Circuit, wherein frequency setting circuit includes low level holding circuit 200, switch off control circuit 300 and the frequency compensation electricity
Road 100;The first end of low level holding circuit 200 and 300 first end of switching off control circuit are separately connected frequency compensation unit
Second end;The second end (i.e. GD in Fig. 3) of low level holding circuit 200 is used to connect the driving pin of PWM chip, shutdown
The second end (i.e. ZCD in Fig. 3) of control circuit is used to connect the measure voltage & current pin (i.e. ZCD pin) of PWM chip;It is low
Level maintaining circuitry 200 is used to export low level according to frequency compensation signal and hold time, and switches off control circuit for according to low
Level is held time control circuit switching frequency.
Specifically, channel frequency refers to the response of dynamic circuit under Stable State of Sine (or system) and the pass of exciting signal frequency
It is (i.e. frequency characteristic).Frequency setting circuit is exactly the frequency for determining setting circuit.Frequency is to determine circuit to be generally used for list
In grade pfc circuit, low level holding circuit 202 is generally included in frequency setting circuit 200 and switches off control circuit 204, wherein
The driving pin of first end connection PWM (pulse width modulation) chip of low level holding circuit 202 is high in driving pin output
When level, switch off control circuit 204 closings, and PWM chip not output driving level, pfc circuit is without frequency response;In driving pin
When exporting low level, switch off control circuit 204 unlatchings, and PWM chip starts output driving level, and pfc circuit has frequency response, separately
Outside, it can also be held by adjusting the parameter of device in 204 that switch off control circuit to adjust the low level of low level holding circuit 202
The continuous time, thus to control the pfc circuit frequency response time.And in the present embodiment, add in original frequency setting circuit
Enter frequency compensated circuit 100, pfc circuit switching frequency is precisely controlled to realize.
Above-mentioned frequency control circuit is due to using above-mentioned frequency compensated circuit, so, it may have frequency compensation electricity
The corresponding beneficial effect in road, it can output frequency value is changed by the voltage signal of input, thus to change opening for circuit
Frequency is closed, the loss to circuit devcie is reduced.In addition, it is easy to use, it is easy to operate.
In one of the embodiments, as shown in figure 4, low level holding circuit 202 includes the 4th resistance R4, the 5th resistance
R5, the 6th resistance R6 and the second NMOS tube Q2;The first end of 4th resistance R4 connects the grid of the second NMOS tube Q2, and passes through the
Five resistance R5 ground connection, the second end of the 4th resistance R4 are used to connect the driving pin of PWM chip;The first end of 6th resistance R6 connects
Meet the drain electrode of the second NMOS tube Q2, the second end TOFF of the second end rate of connections compensating unit of the 6th resistance R6;2nd NMOS
The source electrode of pipe Q2 is grounded GND.
In one of the embodiments, as shown in figure 4, switch off control circuit 204 include third capacitor C3, the 4th capacitor
C4, diode D1, the 7th resistance R7, the 8th resistance R8 and third NMOS tube Q3;The first end rate of connections of third capacitor C3 is mended
The second end TOFF of unit is repaid, the second end of third capacitor C3 is grounded GND;4th capacitor C4 and the 7th resistance R7 are connected to
Between the grid and source electrode of third NMOS tube Q3, and the source electrode ground connection of third NMOS tube Q3, the drain electrode connection of third NMOS tube Q3
The measure voltage & current pin ZCD of PWM chip;The grid of the anode connection third NMOS tube Q3 of diode D1, diode D1's
Cathode is separately connected the first end of the second end TOFF and the 8th resistance R8 of frequency compensation unit, outside the second end of the 8th resistance R8
Connect power supply.
Diode D1 is zener diode in one of the embodiments,.
Zener diode is called Zener diode, is face contact type crystal diode made of a kind of silicon materials, this two pole
Pipe be one kind before critical breakdown reverse voltage all have very high-resistance semiconductor devices, voltage-stabiliser tube in reverse breakdown,
In certain current range (in other words within the scope of certain power loss), end voltage is almost unchanged, and pressure stabilizing is good.In this reality
It applies in example, when VCC charges to third capacitor C3 through resistance R8, when voltage high enough to making diode D1 reverse breakdown
Afterwards, third NMOS tube Q3 starts to work, and diode D1 is defined TOFF ceiling voltage at this time, therefore uses zener diode
It is more accurate to limit TOFF ceiling voltage, and pressure stabilizing is good.
In order to make it easy to understand, as shown in figure 4, the working principle of said frequencies control circuit are as follows: GD connects the driving of PWM chip
Pin, VCC connect the feeder ear of PWM chip, and ZCD connects the ZCD pin of PWM chip, according to the working principle of single- stage PFC circuit, when
GD export high level when, the second NMOS tube Q2 conducting, TOFF voltage is pulled low at this time, and third NMOS tube Q3 does not work, ZCD not by
This circuit influences, and since R8 resistance value is very big, VCC will not be pulled low, and chip can work on;When GD exports low level, VCC
It being charged by R8 to third capacitor C3, voltage is begun to ramp up from 0, when TOFF voltage is greater than the clamp voltage of diode D1, the
Two NMOS tube Q2 conducting, ZCD is pulled low (i.e. ZCD exports low level) at this time, when PWM chip detects that ZCD exports low level,
PWM chip control GD starts output driving level.In addition, said frequencies setting circuit can pass through diode D1, the 8th resistance
The parameter setting of R8 and third capacitor C3 are held time to adjust the low level of GD, and before diode D1 is breakdown, GD can be protected
Low level is held, after diode D1 is breakdown, GD becomes high level.(frequency is precisely controlled to switching frequency so as to realize
The working waveform figure of circuit is as shown in figure 5, wherein VGD refers to that the end GD voltage, Ddrain refer to the drain electrode electricity of the first NMOS tube Q1
Pressure, VZCD refer to the end ZCD voltage).In addition, the frequency setting circuit increases compensation circuit, when voltage collection circuit detects
Voltage input end output high level voltage signal, the first NMOS tube Q1 conducting, the second capacitor C2 is in parallel with third capacitor C3 at this time,
Frequency setting circuit needs the longer charging time that diode D1 could be made to puncture, to reduce circuit switch frequency;When
Voltage collection circuit detects that voltage input end exports low level voltage signal, and the first NMOS tube Q1 is not turned on, the second capacitor C2
Circuit is not accessed, circuit switch frequency is unrelated with compensation circuit at this time.
Each technical characteristic of above embodiments can be combined arbitrarily, for simplicity of description, not to above-described embodiment
In each technical characteristic it is all possible combination be all described, as long as however, the combination of these technical characteristics be not present lance
Shield all should be considered as described in this specification.
Above embodiments only express the several embodiments of the utility model, and the description thereof is more specific and detailed, but simultaneously
The limitation to utility model patent range therefore cannot be interpreted as.It should be pointed out that for the ordinary skill people of this field
For member, without departing from the concept of the premise utility, various modifications and improvements can be made, these belong to this reality
With novel protection scope.Therefore, the scope of protection shall be subject to the appended claims for the utility model patent.
Claims (10)
1. a kind of frequency compensated circuit characterized by comprising voltage sampling circuit, switch unit and frequency compensation unit;
The first end of the voltage sampling circuit is used for input voltage signal, and the second end of the voltage sampling circuit passes through described
Switch unit connects the first end of the frequency compensation unit;The second end of the frequency compensation unit is set for rate of connections
Circuit;
For being opened or closed according to the voltage signal, the frequency compensation unit is used in the switch switch unit
Corresponding frequency compensation signal is exported when unit opens or closes to the frequency setting circuit.
2. frequency compensated circuit according to claim 1, which is characterized in that the voltage sampling circuit includes the first electricity
Resistance, first capacitor and second resistance;
The first end of the first resistor connects the switch for inputting the voltage signal, the second end of the first resistor
Unit;
The first end of the first end of the first capacitor and the second resistance is separately connected the switch unit, first electricity
The second end of the second end of appearance and the second resistance is grounded respectively.
3. frequency compensated circuit according to claim 2, which is characterized in that the voltage sampling circuit further include: third
Resistance;
The second end of the first resistor connects the switch unit by the 3rd resistor.
4. frequency compensated circuit according to claim 3, which is characterized in that the switch unit includes the first NMOS tube;
The grid of first NMOS tube is separately connected the second end of the 3rd resistor, the first end of the first capacitor and institute
State the first end of second resistance, the drain electrode of first NMOS tube connects the first end connection described the of the frequency compensation unit
The drain electrode of one NMOS tube, the source electrode ground connection of first NMOS tube.
5. frequency compensated circuit according to claim 3, which is characterized in that the switch unit includes NPN type triode;
The base stage of the NPN type triode be separately connected the second end of the 3rd resistor, the first end of the first capacitor and
The first end of the second resistance, the collector of the NPN type triode connects the first end of the frequency compensation unit, described
The emitter grounding of NPN type triode.
6. frequency compensated circuit according to claim 4, which is characterized in that the frequency compensation unit includes the second electricity
Hold;
The first end of second capacitor connects the drain electrode of the first NMOS, and the second end of second capacitor connects the frequency
Rate initialization circuit.
7. a kind of frequency control circuit, which is characterized in that including frequency setting circuit and frequency described in any one of claims 1-6
Rate compensation circuit, wherein the frequency setting circuit includes low level holding circuit and switches off control circuit;
The first end of the low level holding circuit and the first end to switch off control circuit are separately connected the frequency compensation
The second end of unit;The second end of the low level holding circuit is used to connect the driving pin of PWM chip, the shutdown control
The second end of circuit is used to connect the measure voltage & current pin of PWM chip;
The low level holding circuit is used to export low level according to the frequency compensation signal to hold time to the shutdown and control
Circuit processed, it is described to switch off control circuit for being held time control circuit switching frequency according to the low level.
8. frequency control circuit according to claim 7, which is characterized in that the low level holding circuit includes the 4th electricity
Resistance, the 5th resistance, the 6th resistance and the second NMOS tube;
The first end of 4th resistance connects the grid of second NMOS tube, and by the 5th resistance eutral grounding, described
The second end of 4th resistance is used to connect the driving pin of the PWM chip;
The first end of 6th resistance connects the drain electrode of second NMOS tube, described in the second end connection of the 6th resistance
The second end of frequency compensation unit;The source electrode of second NMOS tube is grounded.
9. frequency control circuit according to claim 8, which is characterized in that described to switch off control circuit including third electricity
Appearance, the 4th capacitor, diode, the 7th resistance, the 8th resistance and third NMOS tube;
The first end of the third capacitor connects the second end of the frequency compensation unit, the second termination of the third capacitor
Ground;
4th capacitor and the 7th resistance are connected between the grid and source electrode of the third NMOS tube, and described
The source electrode of third NMOS tube is grounded, and the drain electrode of the third NMOS tube connects the measure voltage & current pin of the PWM chip;
The anode of the diode connects the grid of the third NMOS tube, and the cathode of the diode is separately connected the frequency
The first end of the second end of compensating unit and the 8th resistance, the second end external power supply of the 8th resistance.
10. frequency control circuit according to claim 9, which is characterized in that the diode is zener diode.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201820902869.9U CN208367565U (en) | 2018-06-11 | 2018-06-11 | Frequency compensation circuit and frequency control circuit |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201820902869.9U CN208367565U (en) | 2018-06-11 | 2018-06-11 | Frequency compensation circuit and frequency control circuit |
Publications (1)
Publication Number | Publication Date |
---|---|
CN208367565U true CN208367565U (en) | 2019-01-11 |
Family
ID=64928492
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN201820902869.9U Active CN208367565U (en) | 2018-06-11 | 2018-06-11 | Frequency compensation circuit and frequency control circuit |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN208367565U (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN115842522A (en) * | 2023-02-14 | 2023-03-24 | 成都明夷电子科技有限公司 | Doherty power amplifier |
-
2018
- 2018-06-11 CN CN201820902869.9U patent/CN208367565U/en active Active
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN115842522A (en) * | 2023-02-14 | 2023-03-24 | 成都明夷电子科技有限公司 | Doherty power amplifier |
CN115842522B (en) * | 2023-02-14 | 2023-05-23 | 成都明夷电子科技有限公司 | Doherty power amplifier |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN201887469U (en) | Over-voltage protection circuit for radio frequency power amplifier | |
CN110120788A (en) | A kind of biasing circuit and power amplifier for power amplifier | |
CN206807279U (en) | A kind of bridge drive circuit | |
CN209330080U (en) | GaN HEMT protects circuit and equipment | |
CN109768789A (en) | GaN HEMT Drain control circuit and equipment | |
CN109462388A (en) | GaN HEMT control circuit | |
CN208353199U (en) | Atomization piece driving circuit with frequency-tracking | |
CN109742954A (en) | A kind of DC/DC converter | |
CN208367565U (en) | Frequency compensation circuit and frequency control circuit | |
CN207926436U (en) | A kind of start-up circuit of ultralow input voltage | |
CN102664516A (en) | Switching power supply for driving MOS (Metal Oxide Semiconductor) tube | |
CN110880858A (en) | Drive circuit of switching power supply, half-bridge topology switching power supply and electronic equipment | |
CN210985660U (en) | Anti-reverse-filling circuit | |
CN208971481U (en) | Overheating protection circuit for GaN power integration module | |
CN207490898U (en) | The logic level transition device and amplifying circuit of dual power supply amplifier | |
CN208890640U (en) | A kind of booster plate with high safety performance | |
CN206272485U (en) | A kind of dc source is transformed to the circuit of positive and negative dc source | |
CN108303666A (en) | A kind of functional test circuit of power semiconductor modular over-current detection circuit | |
CN205987136U (en) | Television board card power supply protection circuit | |
CN209072053U (en) | A kind of self- recoverage type current foldback circuit | |
CN105515357B (en) | A kind of DCDC current-limiting circuits | |
CN207937585U (en) | A kind of functional test circuit of power semiconductor modular over-current detection circuit | |
CN107222174A (en) | A kind of low-loss adaptive bias circuit and wireless transmitting system | |
CN208707519U (en) | Control switch circuit and switching power supply circuit | |
CN208673174U (en) | A kind of constant-current device applied to AC-DC system |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
GR01 | Patent grant | ||
GR01 | Patent grant |