CN201196658Y - Analog resistor circuit used for device aging screening vehicle - Google Patents

Abstract

The utility model discloses an analog resistance circuit for a part aging and screening vehicle. The analog resistance circuit comprises a field effect transistor VT, a first operational amplifier A1, a second operational amplifier A2, a sampling resistor R10, a first resistor R11, a second resistor R12, a third resistor R13 and a fourth resistor R14. The analog resistance circuit is used for a temperature calibration circuit of the part aging and screening vehicle, changes a resistance value without adjusting a variable resistor, can automatically carry out adjustment and has small error, high calibration efficiency and low cost.

Description

The simulative resistance circuit that is used for device ageing screening lathe

Technical field

The utility model relates to a kind of simulative resistance circuit, relates in particular to a kind of simulative resistance circuit that is used for device ageing screening lathe.

Technical background

Device ageing screening lathe is an Electronic Control production production run in enormous quantities, is used for various devices are carried out the equipment of burn-in screen.Because the device aging screening is carried out under condition of different temperatures, therefore the calibration to temperature is most important.

The common temperature correction circuit that is used for device ageing screening lathe does not use simulative resistance circuit, need to adjust variable resistor, exists like this that efficient is low, the shortcoming of low precision.

Summary of the invention

The purpose of this utility model is to overcome the defective of prior art, and a kind of simulative resistance circuit that is used for device ageing screening lathe is provided, and it has the advantage that error is little, calibration efficiency is high, cost is low.

The technical scheme that realizes above-mentioned purpose is: be used for the simulative resistance circuit of device ageing screening lathe, wherein, it comprises field effect transistor VT, first operational amplifier A ₁, second operational amplifier A ₂, sample resistance R ₁₀, first to fourth resistance R ₁₁～R ₁₄, wherein:

Described second operational amplifier A ₂Positive input terminal be connected with first resistance R ₁₁, negative input end is connected with the 3rd resistance R ₁₃, first resistance R ₁₁The other end and the 3rd resistance R ₁₃The other end between be in series with described sample resistance R ₁₀, this second operational amplifier A ₂Output terminal and described first operational amplifier A ₁Negative input end link to each other;

Described second resistance R ₁₂An end and described second operational amplifier A ₂Positive input terminal link to each other other end ground connection;

Described the 4th resistance R ₁₄An end and described second operational amplifier A ₂Negative input end link to each other the other end and second operational amplifier A ₂Output terminal link to each other;

Described sample resistance R ₁₀With first resistance R ₁₁An end that connects also links to each other with the source electrode of described field effect transistor VT, with the 3rd resistance R ₁₃An end ground connection that connects, voltage is V ₀

The source electrode input steady current of described field effect transistor VT, input voltage is V _x, grid and described first operational amplifier A ₁Output terminal link to each other;

Described first operational amplifier A ₁Positive input terminal import given electric current.

The above-mentioned simulative resistance circuit that is used for device ageing screening lathe, wherein, described first resistance R ₁₁Resistance and the 3rd resistance R ₁₃Resistance equate second resistance R ₁₂Resistance and the 4th resistance R ₁₄Resistance equate.

The above-mentioned simulative resistance circuit that is used for device ageing screening lathe, wherein, described field effect transistor VT is a technotron.

The beneficial effects of the utility model are: simulative resistance circuit of the present utility model is used for the temperature correction circuit of device ageing screening lathe, need not to change resistance by regulating variable resistor, can adjust automatically, and error is little, the calibration efficiency height, and cost is low.

Description of drawings

Fig. 1 is a structural representation of the present utility model.

Embodiment

The utility model is described in further detail below in conjunction with accompanying drawing.

See also Fig. 1, there is shown the simulative resistance circuit that is used for device ageing screening lathe of the present utility model, it comprises field effect transistor VT, first operational amplifier A ₁, second operational amplifier A ₂, sample resistance R ₁₀, first to fourth resistance R ₁₁～R ₁₄, first resistance R ₁₁Resistance and the 3rd resistance R ₁₃Resistance equate, in the present embodiment, second resistance R ₁₂Resistance and the 4th resistance R ₁₄Resistance equate, wherein:

Second operational amplifier A ₂Positive input terminal be connected with first resistance R ₁₁, negative input end is connected with the 3rd resistance R ₁₃, first resistance R ₁₁The other end and the 3rd resistance R ₁₃The other end between be in series with sample resistance R ₁₀, this second operational amplifier A ₂The output terminal and first operational amplifier A ₁Negative input end link to each other second operational amplifier A ₂Form the negative feedback circuit, resistance value R ₁₁=R ₁₃, R ₁₂=R ₁₄, amplifier positive input voltage V ₊Equal reverse input voltage V _-, $V_{+}=\frac{R_{12}}{R_{11}+R_{12}}{V}_1,$ V ₀＝0， $V_{-}=-\frac{R_{11}}{R_{11}+R_{12}}{V}_f,$ Then $V_f=-\frac{R_{12}}{R_{11}}{V}_1=-\frac{R_{12}}{R_{11}}\&CenterDot;{\mathrm{<figure-callout\; id="10"\; label="R"\; filenames="Y200820056802E00071.png"\; state="\{\{state\}\}">R</figure-callout>}}_{10}\&CenterDot;i.;$

Second resistance R ₁₂An end and second operational amplifier A ₂Positive input terminal link to each other other end ground connection;

The 4th resistance R ₁₄An end and second operational amplifier A ₂Negative input end link to each other the other end and second operational amplifier A ₂Output terminal link to each other;

Sample resistance R ₁₀With first resistance R ₁₁An end that connects also links to each other with the source electrode of field effect transistor VT, with the 3rd resistance R ₁₃An end ground connection that connects, voltage is V ₀, V ₀=0V, V ₁=iR ₁₀Because constant current input i is constant constant, be Rx, then Rx=R when requiring Vx to Vo end resistance value _VT+ R ₁₀

The source electrode input steady current of field effect transistor VT, input voltage is V _X, the grid and first operational amplifier A ₁Output terminal link to each other, in the present embodiment, field effect transistor VT is a technotron, resistance under circuit control Vx, the online equivalent resistance simulation in the Vo two ends different temperatures, field effect transistor VT utilizes its transport property, form the basic circuit of artifical resistance, the VT gate-source voltage is directly proportional with the channel resistance of the drain-source utmost point, R _VT=g (Vg-V ₁), g is mutual conductance;

First operational amplifier A ₁Positive input terminal import given electric current, amplifier A ₄Form resistance control circuit, Vg=K (Vi-Vf), K are enlargement factor, and be then according to right 2,3,4, $\mathrm{Rx}=R_{\mathrm{VT}}+{\mathrm{<figure-callout\; id="10"\; label="R"\; filenames="Y200820056802E00071.png"\; state="\{\{state\}\}">R</figure-callout>}}_{10}=>\mathrm{Rx}=g(\mathrm{Vg}-\mathrm{Vi})+\mathrm{<figure-callout\; id="10"\; label="R"\; filenames="Y200820056802E00071.png"\; state="\{\{state\}\}">R</figure-callout>}10=>\mathrm{Rx}=g[K(\mathrm{Vi}-\mathrm{Vf})-\mathrm{Vi}]+{\mathrm{<figure-callout\; id="10"\; label="R"\; filenames="Y200820056802E00071.png"\; state="\{\{state\}\}">R</figure-callout>}}_{10}=>$ $\mathrm{Rx}=g[K(\mathrm{Vi}+\frac{R_{12}}{R_{11}}\&CenterDot;{\mathrm{<figure-callout\; id="10"\; label="R"\; filenames="Y200820056802E00071.png"\; state="\{\{state\}\}">R</figure-callout>}}_{10}\&CenterDot;i)-{\mathrm{<figure-callout\; id="10"\; label="R"\; filenames="Y200820056802E00071.png"\; state="\{\{state\}\}">R</figure-callout>}}_{10}\&CenterDot;i]+{\mathrm{<figure-callout\; id="10"\; label="R"\; filenames="Y200820056802E00071.png"\; state="\{\{state\}\}">R</figure-callout>}}_{10}.$ Because equation the right has only a variable V i, then Mo Ni resistance value simulates required resistance value with linear to determining voltage signal Vi by controlling given signal.

In the present embodiment, field effect transistor VT selects the 3DJ8 technotron for use, i=0.5mA, first, second amplifier A ₁, A ₂Be LM324, sample resistance R ₁₀=20 Ω, R ₁₁=R ₁₃=1K, R ₁₂=R ₁₄=100K, then V ₁=0.01V, V _f=1V.The field effect transistor mutual conductance $g=\frac{1}{100},$ The first amplifier A ₁Enlargement factor K=1000, Rx=10 (Vi-1)+20 then, if need the resistance of 25 ℃ of room temperatures, Rx=100 Ω then, Vi needs given 9V.

Below embodiment has been described in detail the utility model in conjunction with the accompanying drawings, and those skilled in the art can make the many variations example to the utility model according to the above description.Thereby some details among the embodiment should not constitute qualification of the present utility model, and the scope that the utility model will define with appended claims is as protection domain of the present utility model.

Claims (3)

1. be used for the simulative resistance circuit of device ageing screening lathe, it is characterized in that, it comprises field effect transistor VT, first operational amplifier A ₁, second operational amplifier A ₂, sample resistance R ₁₀, first to fourth resistance R ₁₁～R ₁₄, wherein:

Described second operational amplifier A ₂Positive input terminal be connected with first resistance R ₁₁, negative input end is connected with the 3rd resistance R ₁₃, first resistance R ₁₁The other end and the 3rd resistance R ₁₃The other end between be in series with described sample resistance R ₁₀, this second operational amplifier A ₂Output terminal and described first operational amplifier A ₁Negative input end link to each other;

Described second resistance R ₁₂An end and described second operational amplifier A ₂Positive input terminal link to each other other end ground connection;

Described the 4th resistance R ₁₄An end and described second operational amplifier A ₂Negative input end link to each other the other end and second operational amplifier A ₂Output terminal link to each other;

Described sample resistance R ₁₀With first resistance R ₁₁An end that connects also links to each other with the source electrode of described field effect transistor VT, with the 3rd resistance R ₁₃An end ground connection that connects, voltage is V ₀

The source electrode input steady current of described field effect transistor VT, input voltage is V _X, grid and described first operational amplifier A ₁Output terminal link to each other;

Described first operational amplifier A ₁Positive input terminal import given electric current.

2. the simulative resistance circuit that is used for device ageing screening lathe according to claim 1 is characterized in that, described first resistance R ₁₁Resistance and the 3rd resistance R ₁₃Resistance equate second resistance R ₁₂Resistance and the 4th resistance R ₁₄Resistance equate.

3. the simulative resistance circuit that is used for device ageing screening lathe according to claim 1 is characterized in that, described field effect transistor VT is a technotron.

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