CN105699911B

CN105699911B - Power source loads test device

Info

Publication number: CN105699911B
Application number: CN201610012401.8A
Authority: CN
Inventors: 不公告发明人
Original assignee: Zhejiang Jiayuda Machinery Co Ltd
Current assignee: Anhui Wanbang special cable Co., Ltd
Priority date: 2012-06-21
Filing date: 2012-06-21
Publication date: 2018-11-06
Anticipated expiration: 2032-06-21
Also published as: CN105699911A

Abstract

A kind of power source loads test device, for carrying out dynamic load test to a tested power supply, the power source loads test device includes the master controller, function generator and current detection circuit being electrically connected successively, and the function generator is for exporting a square-wave signal；Described draw carries the output current that circuit is used to dynamically change the tested power supply according to the square-wave signal；The current detection circuit is also electrically connected to the master controller, the slope that the current detection circuit is used to that the master controller to be coordinated to detect the output current, the master controller is for the slope of the output current detected to be compared with a default slope value, and accordingly control the function generator according to comparison result and adjust the square-wave signal, until the slope of the output current is equal with the default slope value.

Description

Power source loads test device

Technical field

The present invention relates to a kind of power source loads test device more particularly to a kind of power source loads tests for computer VRM Device.

Background technology

The VRM Voltage Regulator Module (Voltage Regulator Module, VRM) of computer in actual use, institute's band Load is usually dynamic load, that is, the load of VRM changes at any time, and correspondingly, the output current of VRM is also with the change of load Change and is in dynamic change.For example, computer is when entering certain games, the load of VRM institutes band can significantly increase, correspondingly The output current of VRM also significantly increases.

When being tested into Mobile state VRM, generally an electronic load, the electronic load are connected in the output end of VRM Dynamic load test of the output current realization to VRM that situation changes VRM is actually used by simulation.VRM is tested into Mobile state When, under the action of electronic load, the waveform of output current can generally be reduced to square-wave waveform shown in FIG. 1, the output of VRM The rise time that electric current rises to I1 from 0 is t1, wherein the slope of output current, the i.e. drawing of electronic load carry slope and be：I1 with The ratio of rise time t1.According to the difference of load, the drawing load slope of VRM is also different, and sometimes, it is oblique that VRM needs larger drawing to carry Rate loads to drive.

The drawing of current electronic load carries slope generally in 1A/ μ s or so, and is fixed, cannot be satisfied certain VRM To the larger demand for drawing load slope.

Invention content

In view of the above-mentioned problems, providing the larger power source loads test device for drawing load slope it is necessary to provide a kind of.

A kind of power source loads test device is used to carry out dynamic load test to a tested power supply, including electrically connects successively Master controller, function generator, drawing load circuit and the current detection circuit connect, the function generator is for exporting a square wave Signal；Described draw carries the output current that circuit is used to dynamically change the tested power supply according to the square-wave signal, including electricity Press follower, the first mos field effect transistor, load resistance, NPN type triode, PNP type triode, the One power supply and second source, the in-phase input end of the voltage follower are electrically connected to the output of the function generator End, for receiving the square-wave signal, the output end of the voltage follower is electrically connected to first metal oxide half The drain electrode of the grid of conductor field-effect transistor, first mos field effect transistor is electrically connected to institute The output end of tested power supply is stated, the source electrode of first mos field effect transistor passes through the load resistance Ground connection, and the node between the source electrode and the load resistance of first mos field effect transistor is electrical It is connected to the inverting input of the voltage follower；The output end of the voltage follower is electrically connected to the NPN type three The collector of the base stage of pole pipe and the PNP type triode, the NPN type triode is electrically connected to first power supply；Hair Emitter-base bandgap grading is electrically connected to the emitter of the PNP type triode, and the transmitting of the NPN type triode and PNP type triode Node between pole is electrically connected to the grid of first mos field effect transistor；The positive-negative-positive three The collector of pole pipe is electrically connected to the second source；The NPN type triode and PNP type triode are described for enhancing The driving capability of the first mos field effect transistor of square-wave signal pair avoids the square-wave signal distortion can not The first mos field effect transistor of normal driving；The current detection circuit is also electrically connected to the master control Device processed, the slope that the current detection circuit is used to that the master controller to be coordinated to detect the output current, the master controller For the slope of the output current detected to be compared with a default slope value, and accordingly controlled according to comparison result The function generator adjusts the square-wave signal, until the slope of the output current is equal with the default slope value.

In the present invention power source loads test device by main controller controls function generator to the waveform of square-wave signal into Row is adjusted, so as to carry the drawing load slope that circuit accordingly adjusts the power source loads test device by drawing, so as to as needed It obtains larger drawing and carries slope.In addition, according to the different default slope values that keyboard circuit inputs, the power source loads test dress Setting, which can also accordingly obtain different drawings, carries slope, therefore, has preferable versatility.

Description of the drawings

Fig. 1 is output current wave figures of the existing VRM when being tested into Mobile state.

Fig. 2 is the functional block diagram of the power source loads test device of better embodiment of the present invention.

Fig. 3 is the circuit diagram of power source loads test device shown in Fig. 2.

Main element symbol description

Power source loads test device 100

VRM 200

Master controller 10

Function generator 20

It draws and carries circuit 30

Current detection circuit 40

Enabled circuit 50

Keyboard circuit 60

Display 70

Output current Io

Current detecting pin P1

Controlling switch P2

Voltage follower U1

Operational amplifier U2

First MOSFET Q1

NPN type triode Q2

PNP type triode Q3

2nd MOSFET Q4

Load resistance R0

Filter resistance R1

Current-limiting resistance R2-R8, R10

Feedback resistance R9

Filter capacitor C1

In-phase input end 1,5

Inverting input 2,6

Output end 3,7

Control terminal 4,8

Grid g1, g2

Source electrode s1, s2

Drain d1, d2

Base stage b1, b2

Collector c1, c2

Emitter e 1, e2

Following specific implementation mode will be further illustrated the present invention in conjunction with above-mentioned attached drawing.

Specific implementation mode

Referring to Fig. 2, the power source loads test device 100 of better embodiment of the present invention is used to carry out a tested power supply Dynamic load is tested.In the present embodiment, the present invention will be described so that the tested power supply is a VRM200 as an example.

Power source loads test device 100 includes master controller 10, function generator 20, draws load circuit 30, current detecting electricity Road 40, enabled circuit 50, keyboard circuit 60 and display 70.Function generator 20 is for generating a square-wave signal；It draws and carries electricity Road 30 is used to dynamically change the output current of VRM200 according to the square-wave signal；Current detection circuit 40 is for coordinating master control Device 10 processed detects the output current Io of VRM200, i.e. load current, to obtain the slope of output current Io；The master controller 10 for the slope of output current Io to be compared with a default slope value, and is occurred according to the corresponding control function of comparison result Device 20 adjusts the waveform of the square-wave signal, until the slope of output current Io is equal with the default slope value.

Also referring to Fig. 3, master controller 10 includes the current detecting pin P1 for being electrically connected to current detection circuit 40 And it is electrically connected the controlling switch P2 for enabling circuit 50.

It includes voltage follower U1, the first mos field effect transistor (Metal- to draw and carry circuit 30 Oxide-Semiconductor Field-Effect Transistor, MOSFET) Q1, load resistance R0, filter resistance R1, Current-limiting resistance R2-R5 and filter capacitor C1.Voltage follower U1 include in-phase input end 1, inverting input 2, output end 3 with And control terminal 4.The in-phase input end 1 of voltage follower U1 is electrically connected to function generator 20 by current-limiting resistance R2, is used for Receive the square-wave signal；Inverting input 2 passes sequentially through filter resistance R1 and filter capacitor C1 is electrically connected to output end 3； Output end 3 is electrically connected to the grid g1 of the first MOSFET Q1 by current-limiting resistance R3；Control terminal 4 is electrically connected to enabled electricity Road 50.The source electrode s1 of first MOSFET Q1 is grounded by load resistance R0, and source electrode s1 is also electrically connected to voltage follower U1's Inverting input 2；The drain electrode d1 of first MOSFET Q1 is electrically connected to the output end of VRM200.In the present embodiment, source electrode S1 is electrically connected the inverting input 2 of voltage follower U1 by current-limiting resistance R5.Current-limiting resistance R5 is for preventing voltage follow Electric current on the inverting input 2 of device U1 impacts the test of the output current Io of VRM.

Voltage on the output end 3 of voltage follower U1 and the arc in phase on its in-phase input end 1, and voltage follower The amplification factor of U1 is approximately 1, and therefore, the signal that the output end 3 of voltage follower U1 exports is the square-wave signal, described Square-wave signal drives the first MOSFET Q1 to sequentially turn on and end, to which VRM200 generates one dynamically on load resistance R0 Electric current, i.e. the output current Io of VRM200.

According to the resolution of operational amplifier, the electric current of the inverting input 2 of voltage follower U1 is approximately zero, because This, the pressure drop very little on current-limiting resistance R5, the current potential on the source electrode s1 of the first MOSFET Q1 is approximately equal to voltage follower U1's The current potential of inverting input 2.According to the short characteristic of void of operational amplifier, the current potential of the in-phase input end 1 of voltage follower U1 with The current potential of inverting input 2 is equal, and therefore, the amplitude of the current potential on the source electrode s1 of the first MOSFET Q1 is believed equal to the square wave Number amplitude.And the electric current on load resistance R0, the i.e. value of output current Io are equal to current potential and load resistance R0 on source electrode s1 Resistance value quotient, in this way, passing through the amplitude for changing the square-wave signal, you can the size for changing output current Io, in phase In the case of the same rise time, output current Io is bigger, then its slope is bigger.Further, since the amplitude of the square-wave signal When change, the amplitude of output current Io also changes correspondingly, and therefore, output current Io has rising identical with the square-wave signal Time, fall time, frequency and duty ratio also may be used by changing the rise time and fall time of the square-wave signal The corresponding rise time and fall time for changing output current Io, in the case where output current Io amplitudes are constant, the rise time And fall time is bigger, then its slope is smaller.

In the present embodiment, it further includes NPN type triode Q2 and PNP type triode Q3 to draw and carry circuit 30.NPN type three Pole pipe Q2 and PNP type triode Q3 is used to enhance the driving capability of the first MOSFET Q1 of the square-wave signal pair, avoids described Square-wave signal distortion can not the first MOSFET Q1 of normal driving.Specifically, the output end 3 of voltage follower U1 passes through current limliting electricity Resistance R5 is electrically connected to base stage b1, b2 of NPN type triode Q2 and PNP type triode Q3.The collector c1 of NPN type triode Q2 It is electrically connected to+5V power supplys；Emitter e 1 is electrically connected to the emitter e 2 of PNP type triode Q3, and between emitter e 1, e2 Node the grid g1 of the first MOSFET Q1 is electrically connected to by current-limiting resistance R3.The collector c2 electricity of PNP type triode Q3 Property is connected to -5V power supplys.In addition, when the first MOSFET Q1 cut-offs, PNP type triode Q3 is additionally operable to make the first MOSFET Q1 Interior charging capacitor (not shown) is grounded rapidly electric discharge, to make the first MOSFET Q1 quickly end, to improve first The response speed of MOSFET Q1.

Current detection circuit 40 includes operational amplifier U2, current-limiting resistance R6-R8 and feedback resistance R9.Operational amplifier U2 includes in-phase input end 5, inverting input 6, output end 7 and control terminal 8.The in-phase input end 5 of operational amplifier U2 is logical Cross the node that current-limiting resistance R6 is electrically connected between load resistance R0 and source electrode s1；And in-phase input end 5 and current-limiting resistance R6 Between node be also grounded by current-limiting resistance R8.Inverting input 6 is electrically connected to load resistance R0 by current-limiting resistance R7 Node between ground；And the node between inverting input 6 and current-limiting resistance R7 is also electrically connected to by feedback resistance R9 Output end 7.Output end 7 is electrically connected to master controller 10.Described in operational amplifier U2 is used to flow through on load resistance R0 Voltage signal is converted into after output current Io amplifications to export to the current detecting pin P1 of master controller 10,10 basis of master controller The voltage signal accordingly calculates output current Io, to judge to export according to the variation of output current Io on load resistance R0 The slope of electric current Io.

Enabled circuit 50 is electrically connected to master controller 10, and master controller 10 is drawn by the enabled control of circuit 50 and carries circuit 30 And the working condition of current detection circuit 40.Specifically, it includes the 2nd MOSFET Q4 and current-limiting resistance to enable circuit 50 R10.The grid g2 of 2nd MOSFET Q4 is electrically connected to the controlling switch P2 of master controller 10, source electrode s2 ground connection, grid d2 electricity Property is connected to the control terminal 4,8 of voltage follower U1 and operational amplifier U2.The control of voltage follower U1 and operational amplifier U2 End 4,8 processed and drain electrode d2 between node a power supply is also electrically connected to by current-limiting resistance R10, as in present embodiment+ 5V power supplys.Master controller 10 passes through the conducting and cut-off of the 2nd MOSFET Q4 of control, the corresponding level shape for changing control terminal 4 and 8 State starts to work or is stopped to control voltage follower U1 and operational amplifier U2.In the present embodiment, control terminal 4 and 8 be that high level is effective.In this way, when master controller 10 sends a low level signal (logical zero) to the by controlling switch P2 When two MOSFET Q4, the 2nd MOSFET Q4 cut-offs, control terminal 4 and 8 is by current-limiting resistance R10 is connected to+5V power supplys in height Level, voltage follower U1 and operational amplifier U2 start to work；And when master controller 10 is high by controlling switch P2 transmissions one When level signal (logic 1) is to the 2nd MOSFET Q4, the 2nd MOSFET Q4 conductings, control terminal 4 and 8 passes through the 2nd MOSFET Q4 is grounded and is in low level, and voltage follower U1 and operational amplifier U2 are stopped.

It is appreciated that the enabled circuit 50 can also be only connected to voltage follower U1 or operational amplifier U2 wherein One, to which master controller 10 only controls the working condition of one of voltage follower U1 or operational amplifier U2 System.

In the present embodiment, the default slope value is inputted by the keyboard circuit 60 for being electrically connected to master controller 10. Different default slope values is inputted by keyboard circuit 60, can so that drawing load circuit 30 to obtain different drawings carries slope.In addition, The parameters such as amplitude, rise time, fall time, frequency and the duty ratio of the square-wave signal that function generator 20 exports It can be inputted by the keyboard circuit 60, master controller 10 receives each parameter of the square-wave signal by keyboard circuit 60, and The corresponding square-wave signal is exported according to each state modulator function generator 20.

Display 70 is electrically connected to the master controller 10, for showing keyboard circuit under the control of master controller 10 The default slope value of 60 inputs and each parameter of the square-wave signal.

The course of work of power source loads test device 100 described in brief description：

The drain electrode d1 for the first MOSFET Q1 for carrying circuit 30 is drawn to be electrically connected to a tested power supply by described first, such as originally VRM200 to be measured in embodiment.Then keyboard circuit 60 inputs the width of the default slope value and the square-wave signal first The parameters such as value, rise time, fall time, frequency and duty ratio.Master controller 10 controls display 70 and shows keyboard circuit The above- mentioned information of 60 inputs, while according to function generator 20 described in each state modulator of the square-wave signal of the input of keyboard circuit 60 The corresponding square-wave signal of output, subsequent master controller 10 are drawn by the enabled control of circuit 50 and carry circuit 30 and current detecting Circuit 40 is started to work, and is drawn and is carried circuit 30 then according to the square-wave signal driving VRM200 corresponding output current Io of output, electricity Then cooperation master controller 10 detects the variation of the output current Io accordingly to judge the output electricity to current detection circuit 40 Flow the slope of Io.The slope of the output current Io detected is compared by master controller 10 with the default slope value again, and The amplitude of the square-wave signal and/or rise time and fall time are carried out according to comparison result control function generator 20 micro- It adjusts, until the slope of output current Io is equal with the default slope value.

At this point, power source loads test device 100 can be equivalent to a dynamic electronic load, in power source loads test device Under the action of 100 so that the output current Io of VRM200 is in dynamic change, realizes and tests the dynamic of VRM200.

The power source loads test device 100 is by 10 control function generator 20 of master controller to the wave of square-wave signal Shape is adjusted, and the drawing so as to accordingly adjust the power source loads test device 100 by drawing load circuit 30, which carries slope, makes it reach To the default slope value, larger drawing load slope can be obtained so as to be arranged as required to the default slope value.In addition, According to the different default slope values that keyboard circuit 60 inputs, the power source loads test device 100 can also accordingly obtain difference Drawing carry slope, therefore, have preferable versatility.

Claims

1. a kind of power source loads test device, for carrying out dynamic load test to a tested power supply, it is characterised in that：The electricity Source load testing device includes the master controller being electrically connected successively, function generator, draws load circuit and current detection circuit, The function generator is for exporting a square-wave signal；The drawing carries circuit and is used to dynamically change institute according to the square-wave signal State the output current of tested power supply, including voltage follower, the first mos field effect transistor, load electricity Resistance, NPN type triode, PNP type triode, the first power supply and second source, the in-phase input end electricity of the voltage follower Property be connected to the output end of the function generator, for receiving the square-wave signal, the output end electricity of the voltage follower Property is connected to the grid of first mos field effect transistor, first MOS field The drain electrode of effect transistor is electrically connected to the output end of the tested power supply, first metal oxide semiconductor field-effect The source electrode of transistor is grounded by the load resistance, and the source electrode of first mos field effect transistor Node between the load resistance is electrically connected to the inverting input of the voltage follower；The voltage follower Output end is electrically connected to the base stage of the NPN type triode and the PNP type triode, the current collection of the NPN type triode Pole is electrically connected to first power supply；Emitter is electrically connected to the emitter of the PNP type triode, and the NPN type Node between triode and the emitter of PNP type triode is electrically connected to first metal oxide semiconductcor field effect Answer the grid of transistor；The collector of the PNP type triode is electrically connected to the second source；The NPN type triode And PNP type triode is used to enhance the driving energy of the first mos field effect transistor of the square-wave signal pair Power avoids the square-wave signal distortion can not the first mos field effect transistor of normal driving；The electric current Detection circuit is also electrically connected to the master controller, and the current detection circuit is for coordinating described in the master controller detection The slope of output current, the slope for the output current that the master controller is used to detect and a default slope value carry out Compare, and the function generator is accordingly controlled according to comparison result and adjusts the square-wave signal, until the output current Slope is equal with the default slope value.

2. power source loads test device as described in claim 1, it is characterised in that：The master controller is by controlling the letter Number generator changes (i) amplitude and/or (ii) rise time and the fall time of the square-wave signal to adjust the output The slope of electric current.

3. power source loads test device as claimed in claim 2, it is characterised in that：It further includes filter resistance that the drawing, which carries circuit, And filter capacitor, the inverting input of the voltage follower passes sequentially through the filter resistance and filter capacitor electrically connects It is connected to the output end of the voltage follower.