阅读说明：本技术 一种电子负载电路 (A kind of electronic load circuit ) 是由 李科锋 周利红 罗玉奎 于 2019-08-23 设计创作，主要内容包括：本发明公开了一种电子负载电路,用于对测试源进行测试,包括电压采样放大电路、模数转换电路、电流采样放大电路、控制电路、负载电路,控制电路用于接收模数转换电路输出的数据,并输出控制信号给负载电路,电压采样放大电路用于对测试源的电压进行采样,并把采样结果传输给模数转换电路,负载电路用于根据控制电路输出的控制信号,检测测试源的负载能力,电流采样放大电路用于采集流过负载电路的电流大小,并将采集结果传输给模数转换电路。本申请通过检测电压与电流,并根据检测结果,控制功率管的导通与截止,从而实现对负载能力的控制,使电子负载适用于多种情况的测试,扩大了电子负载的应用,减小了浪费。(The invention discloses a kind of electronic load circuits, for testing test source, including voltage sample amplifying circuit, analog to digital conversion circuit, current sample amplifying circuit, control circuit, load circuit, control circuit is used to receive the data of analog to digital conversion circuit output, and control signal is exported to load circuit, voltage sample amplifying circuit is for sampling the voltage of test source, and sampled result is transferred to analog to digital conversion circuit, load circuit is used for the control signal exported according to control circuit, detect the load capacity of test source, current sample amplifying circuit is for acquiring the size of current for flowing through load circuit, and collection result is transferred to analog to digital conversion circuit.The application controls the conducting and cut-off of power tube by detection voltage and electric current, and according to testing result, to realize the control to load capacity, so that electronic load is suitable for the test of a variety of situations, expands the application of electronic load, reduce waste.)

1. a kind of electronic load circuit, for testing test source, it is characterised in that: including voltage sample amplifying circuit, Analog to digital conversion circuit, current sample amplifying circuit, control circuit, load circuit, control circuit respectively with analog to digital conversion circuit, negative Circuit connection is carried, for receiving the data of analog to digital conversion circuit output, and exports control signal to load circuit, voltage sample is put Big circuit, load circuit and test source connect, and voltage sample amplifying circuit is for sampling the voltage of test source, and handle is adopted Sample result is transferred to analog to digital conversion circuit, and load circuit is used for the control signal exported according to control circuit, detects test source Load capacity, current sample amplifying circuit are connect with load circuit, analog to digital conversion circuit respectively, flow through load circuit for acquiring Size of current, and collection result is transferred to analog to digital conversion circuit.

2. electronic load circuit according to claim 1, it is characterised in that: the load circuit includes that two-way opened is powered-down Road, control switch circuit, driving circuit, power tube, the input terminal of the driving circuit connect control circuit, output end connection The control terminal of power tube, for being worked according to the output driving power tube of control circuit；The input terminal of control switch circuit connects Control circuit, output end connect the control terminal of bidirectional switch circuit, for controlling two-way switch according to the output of control circuit The on or off of circuit；Current sample amplifying circuit is connected between bidirectional switch circuit, power tube, flows through function for detecting The size of current of rate pipe, output are separately connected control circuit and analog to digital conversion circuit, the output end ground connection of power tube.

3. electronic load circuit according to claim 2, it is characterised in that: between the input terminal and output end of power tube Cooling fan in parallel works for the energy driving cooling fan using test source.

4. electronic load circuit according to claim 1, it is characterised in that: further include telecommunication circuit, with control circuit Input terminal connection, the communication for control circuit and periphery.

5. electronic load circuit according to claim 1, it is characterised in that: further include watchdog circuit, with control circuit Connection, for protecting data.

6. electronic load circuit according to claim 1, it is characterised in that: further include temperature sensing circuit, with control electricity Road connection, for the temperature of measured power pipe, and will test result and inputs to control circuit.

7. electronic load circuit according to claim 1, it is characterised in that: voltage sample amplifying circuit, current sample are put Big circuit respectively includes instrumentation amplifier, is respectively used to amplify acquisition data.

8. electronic load circuit according to claim 7, it is characterised in that: voltage sample amplifying circuit further includes partial pressure electricity Road, voltage follower circuit, the output end of the input terminal connection instrumentation amplifier of the bleeder circuit, for amplified sampling Voltage is divided, and the output end of the input terminal connection bleeder circuit of the voltage follower circuit, output end connects modulus and turns Change circuit.

Technical field

The present invention relates to the field of test technology, more particularly, to a kind of electronic load circuit.

Background technique

Power supply class consumer electronics in process of production, are needed just to can guarantee quality by function and burn-in test, tested When require to use electronic load the load-bearing capacity of product assessed, the performance of electronic load largely influences such The test quality of product.

When existing electronic product is tested, two power supplys are needed, one is used to power to test source, and one for electronics Load supplying, under normal circumstances, the mode that electronic load consumes the energy of application is realized by the fever of power tube, is Realize the protection to power tube, power tube needs to cooperate cooling fan, and cooling fan is by mentioning the power supply that electronic load is powered For the fever of power tube causes the waste of electric energy, and when especially high-power, the fever of power tube is serious, the energy of test source Amount is wasted, and cooling fan also consumes the electric energy of electronic load.

Existing electronic load, using constant control mode, i.e., by analog-digital converter, current sampling, compare amplifying unit, Load pipe constitutes hardware closed-loop circuit, and circuit feature is easy solidification, wants when the product of test changes to loop characteristics Ask different, it is necessary to readjust hardware circuit, cause the consumption of resource, manpower etc..

Therefore, design a kind of electronic load for being applicable to a variety of situations, make full use of test source electric energy, be at present urgently It solves the problems, such as.

Summary of the invention

The object of the present invention is to provide a kind of electronic load circuits, and control circuit is arranged and is used to provide different loads, makes Electronic load circuit is suitable for the test source of a variety of situations, reduces the waste of resource, manpower, meanwhile, using test source current It powers to cooling fan, on the one hand reduces the waste of electric energy, on the other hand reduce the fever of power tube again.

Foregoing invention purpose of the invention is achieved by the following technical programs:

A kind of electronic load circuit, for testing test source, including voltage sample amplifying circuit, analog to digital conversion circuit, Current sample amplifying circuit, control circuit, load circuit, control circuit are connect with analog to digital conversion circuit, load circuit respectively, are used In the data of reception analog to digital conversion circuit output, and control signal is exported to load circuit, voltage sample amplifying circuit, load electricity Road is connect with test source, and voltage sample amplifying circuit is transferred to sampled result for sampling to the voltage of test source Analog to digital conversion circuit, load circuit are used for the control signal exported according to control circuit, detect the load capacity of test source, electric current Amplifier circuit is connect with load circuit, analog to digital conversion circuit respectively, for acquiring the size of current for flowing through load circuit, and Collection result is transferred to analog to digital conversion circuit.

The present invention is further arranged to: the load circuit includes bidirectional switch circuit, control switch circuit, driving electricity Road, power tube, the input terminal of the driving circuit connect control circuit, and output end connects the control terminal of power tube, are used for root It works according to the output driving power tube of control circuit；The input terminal of control switch circuit connects control circuit, output end connection The control terminal of bidirectional switch circuit controls the on or off of bidirectional switch circuit for the output according to control circuit；Electric current Amplifier is electrically connected between bidirectional switch circuit, power tube, for the size of current of detection stream overpower pipe, output It is separately connected control circuit and analog to digital conversion circuit, the output end ground connection of power tube.

The present invention is further arranged to: the cooling fan in parallel between the input terminal and output end of power tube, for utilizing The energy driving cooling fan work of test source.

The present invention is further arranged to: being further included telecommunication circuit, is connect with the input terminal of control circuit, is used for control circuit With the communication of periphery.

The present invention is further arranged to: being further included watchdog circuit, is connected to the control circuit, for protecting data.

The present invention is further arranged to: being further included temperature sensing circuit, is connected to the control circuit, for measured power pipe Temperature, and will test result and input to control circuit.

The present invention is further arranged to: voltage sample amplifying circuit, current sample amplifying circuit respectively include instrument amplification Device is respectively used to amplify acquisition data.

The present invention is further arranged to: voltage sample amplifying circuit further includes bleeder circuit, voltage follower circuit, and described point The output end of the input terminal connection instrumentation amplifier of volt circuit, for being divided to amplified sampled voltage, the voltage The input terminal of circuit is followed to connect the output end of bleeder circuit, output end connects control circuit.

Compared with prior art, advantageous effects of the invention are as follows:

1. the application controls the conducting and cut-off of power tube, to realize by detection voltage and electric current, and according to testing result Control to load capacity makes electronic load be suitable for the test of a variety of situations, expands the application of electronic load, reduce wave Take；

2. further, the application realizes the shunting to power tube, that is, drops by the way that cooling fan is attempted by power tube both ends Low energy consumption, decreases the fever of power tube.

Detailed description of the invention

Fig. 1 is the electrical block diagram of a specific embodiment of the invention；

Fig. 2 is the load circuit structural schematic diagram of a specific embodiment of the invention；

Fig. 3 is the cooling fan parallel circuit structure schematic diagram of a specific embodiment of the invention.

Specific embodiment

Below in conjunction with attached drawing, invention is further described in detail.

A kind of electronic load circuit of the invention, for testing test source, as shown in Figure 1, including voltage sample Amplifying circuit, analog to digital conversion circuit, current sample amplifying circuit, control circuit, load circuit, control circuit are adopted with voltage respectively Sample amplifying circuit, analog to digital conversion circuit, current sample amplifying circuit, load circuit connection, it is defeated for receiving analog to digital conversion circuit Data out, and control signal is exported to load circuit；Voltage sample amplifying circuit, load circuit and test source connect, voltage Amplifier circuit is transferred to analog to digital conversion circuit, load electricity for sampling to the voltage of test source, and sampled result Road is used for the control signal exported according to control circuit, detects the load capacity of test source；Current sample amplifying circuit respectively with Load circuit, analog to digital conversion circuit connection, are transferred to mould for acquiring the size of current for flowing through load circuit, and by collection result Number conversion circuit.

Control circuit is according to collected voltage signal and current signal, the electric conduction of output control signal control power tube Size is flowed, to realize the test to test source voltage, electric current or power etc..

Preferably, the control signal of control circuit output is pwm signal, according to the frequency and duty ratio of pwm signal, control The conducting electric current of power tube.

In the specific embodiment of the application, load circuit includes bidirectional switch circuit, control switch circuit, driving Circuit, power tube P；One output end of the input terminal connection control circuit of driving circuit, output end connect the control of power tube P End processed, for being worked according to the output signal driving power pipe P of control circuit；The input terminal connection control electricity of control switch circuit The another output on road, output end connects the control terminal of bidirectional switch circuit, for the output signal according to control circuit The on or off for controlling bidirectional switch circuit connects the connection of power tube P load and test source in conducting, disconnected in cut-off Open the connection of power tube P load and test source.

Current sample amplifying circuit is connected between bidirectional switch circuit, power tube, the electricity for detection stream overpower pipe P Flow size, output be separately connected control circuit and analog to digital conversion circuit, collected current signal be transferred to control circuit, Collected simulation current flow is converted to digital current amount and digital current amount is passed by analog to digital conversion circuit, analog to digital conversion circuit It is defeated by control circuit, control circuit adjusts the switch of power tube according to the collected magnitude of current, to realize the control to electric current.

Current sample amplifying circuit includes sampling resistor, instrumentation amplifier, filter circuit, the both ends of sampling resistor respectively with Two input terminals of instrumentation amplifier connect, for the voltage at collected sampling resistor both ends to be amplified, instrument amplification The output of device is transferred to analog to digital conversion circuit after filter circuit.Current signal analog is converted to electricity by analog to digital conversion circuit Signal digital quantity is flowed, and is transferred to control circuit.

Control switch circuit includes the first driving circuit, and the control switch signal driving for being exported according to control circuit is double To switch motion.

First driving circuit includes comparison amplifier, for increasing the driving capability of control switch signal.

Similarly, driving circuit includes comparison amplifier, for increasing the driving capability of control driving signal, is realized to function The driving of rate pipe P.

The output end of power tube is grounded.

Control circuit includes MCU.In the periphery of MCU, watchdog circuit is designed, is connected to the control circuit, for protecting number According to.

Although including analog-digital conversion function in MCU, since the various aspects such as its precision cannot reach requirement, so in circuit Middle setting analog to digital conversion circuit,

Analog to digital conversion circuit is connected between control circuit and voltage sample amplifying circuit, current sample amplifying circuit, and being used for will Sampled voltage analog quantity, sample rate current analog quantity are converted into sampled voltage digital quantity, sample rate current digital quantity respectively, and are transferred to Control circuit.

In another specific embodiment of the application, load circuit further includes cooling fan Z, and cooling fan Z is connected in parallel on Between the input terminal and output end of power tube, when power tube has electric current to flow through, also there is electric current to flow through on cooling fan Z, a side Cooling fan Z work in face reduces the heat on the surface power tube P, and on the other hand, cooling fan Z reduces the electricity for flowing through power tube P Flow reduces the fever of power tube P, takes full advantage of the electric energy of test source, reduces the waste of the energy.With two-way switch reality Now to the control of cooling fan Z working condition.

In another specific embodiment of the application, voltage sample amplifying circuit include instrumentation amplifier, bleeder circuit, Two input terminals of voltage follower circuit, instrumentation amplifier are separately connected the both ends of voltage sample or the voltage output of test source End, for carrying out amplifier to sampled voltage or test source voltage, the input terminal of output end connection bleeder circuit, control are opened The one end on powered-down road provides pull-up power supply for an input terminal to control switch circuit；The input terminal of bleeder circuit connects The output end of instrumentation amplifier, for dividing to amplified sampled voltage, the input terminal of the voltage follower circuit connects The output end of bleeder circuit is connect, output end connects analog to digital conversion circuit.

In another specific embodiment of the application, electronic load circuit further includes telecommunication circuit, with control circuit Input terminal connection receives the control letter that peripheral control circuits such as host computer issues for the both-way communication of control circuit and periphery Number, the acquisition data or work state information for transmitting electronic load circuit are to peripheral control circuits.

In another specific embodiment of the application, electronic load circuit further includes temperature sensing circuit, with control electricity Road connection, for the temperature of measured power pipe, and will test result and inputs to control circuit.

Control circuit flows through the size of current of power tube according to test temperature, control.

Control circuit can be realized the real-time control to electronic load circuit, change the work shape of electronic load circuit in real time State, enable electronic load circuit be suitable for a variety of situations, expand the scope of application of electronic load circuit, reduce resource, The consumption of manpower etc..

The embodiment of present embodiment is presently preferred embodiments of the present invention, not limits protection of the invention according to this Range, therefore: the equivalence changes that all structures under this invention, shape, principle are done, should all be covered by protection scope of the present invention it It is interior.