SU1164637A1 - Device for visual indication of characteristics of semiconductor devices - Google Patents

Abstract

1. DEVICE FOR VISUAL INDICATION OF SEMICONDUCTOR DEVICES CHARACTERISTICS containing an electronic switch connected by the first and second outputs to the control inputs of the first and second keys, respectively, the third output to the control inputs of the third and fourth keys, the fourth output to the control inputs of the first and second keys, the sixth keys, the outputs of the first, third and fifth keys are connected to the corresponding inputs of the first OR element connected to the output X of the oscilloscope connected by the input Y to the output The second OR element connected by the first, second and third inputs to the outputs of the second, fourth and sixth keys, the output of the clock generator is connected to the input of the electronic switch, to the input of the linearly decreasing voltage generator and with the input of the linearly rising voltage connected to the output - information inputs of the first and second keys and with the first output voltage of the first voltage divider connected by the second output to the common input device, the third output — to the information input the third the key, the generator output of the linearly decreasing voltage is connected to the first output of the second voltage divider connected by the second output to the common bus of the device, the third output through the first collector resistor and the first rheostat to the common bus of the device, the first differential amplifier, connected by the output to the information input of the sixth key, the second current collector resistor connected by the first output to the first output of the second rheostat, the first and second terminals for connecting the semiconductor ovogo device, characterized in that, in order povsh1eni precision devices incorporated therein a source of DC voltage, the third voltage divider. the seventh, eighth, dev tel and tenth tiaab e keys, the second differential amplifier, the first and second pulsed (35 voltmeters, with the FIVE output of the electronic switchboard connected to the control input of the seventh key,: Od connected by an information input to the sj third the output of the first voltage divider, the output to the first input of the third OR element connected, the second input to the output of the eighth key connected by the control input to the sixth output of the electronic switch, and the control inputs of the ninth and tenth whose, data input - from perbELM terminal of the third voltage divider connected with the second terminal of the output uc

Description

a constant voltage source, the third output - with a common bus device connected to the first terminal for connecting a semiconductor device, the second terminal for connecting which is connected to the information inputs of the ninth and fifth keys and the second output of the second rheostat connected to the first output of the first the input of the first differential amplifier connected by the second input to the second output of the second current collector resistor and to the output of the third OR element, the output to the information input of the tenth key first and the second inputs of the second differential unit. connectors are connected respectively with the same terminals of the first collector resistor, the output is with the information input of the fourth key, the inputs are first 64637

first and second pulse voltmeters are connected respectively to the outputs of the ninth and tenth keys. 2. The device according to claim 1, about tl and so that the electronic switch contains a frequency divider connected to the input of the electronic switch and the first input of the RS-trnger connected to the second input to the output of the frequency divider, the output to the delay line input connected by first, second,. the third, fourth and fifth taps, respectively, with the first, second, third, fifth and sixth outputs of the electronic switch connected to the fourth output of the fourth element OR, connected by the first and second inputs to the fourth and fifth taps of the delay line, respectively.

one

The invention relates to instrumentation technology and may be. used to remove current-voltage characteristics of semiconductor devices.

A device for visual observation of the p-junction volt-ampere characteristics is known, which contains a triangular voltage source, a beam modulation unit, an oscilloscope, a resistor, summation, synchronization blocks, an adjustable delay, a square-wave generator, and a Homoidal limiter of a well-known device; Limited functional capabilities due to the fact that it does not allow to determine the position of the operating point of the semiconductor device. ,

The closest to the present invention is a device for visual indication of the characteristics of semiconductor devices, containing an electronic switch connected by the first and second outputs to the control inputs of the first and second keys, respectively, the third output of the third and

the fourth key, the fourth output — with the control inputs of the fifth and sixth keys; the outputs of the first, third, and fifth keys are connected to the corresponding inputs of the first OR element connected by the output to the X input of the oscilloscope connected by the Y input to the output of the second OR element connected by the first , the second and third inputs with the outputs of the second, fourth and sixth keys, the output of the clock generator is connected to the input of the electronic switch, to the input of the generator of linearly decreasing voltage and to the input of the generator and the linearly increasing voltage connected by the output to the information inputs of the first and second keys and to the first output of the first divider connected by the second output to the common bus of the device, the third output to the information input of the third key, the output of the linearly decreasing voltage the output of the second divider connected by the second output: to the common bus of the device, the third output via serially connected first current collector resistor and rheostat - to the common bus of the device, the first differential A potential amplifier connected by an output to the information input of a sixth switch, a second choke resistor connected by a first output to a first output of a second rheostat, first and second resistors, amplifiers 1121. A disadvantage of the known device is the low precision of setting the operating point of a semiconductor device due to those The point of intersection of the load current with the current-voltage characteristic is set by the operator visually, and therefore, the location of the working point and the accuracy of determining the coordinate atm current-voltage characteristics depend on the characteristics of subjects GOVERNMENTAL operator view. The purpose of the invention is to improve the accuracy of the device. The goal is achieved in a device for visual indication of the characteristics of semiconductor devices containing an electronic switch connected by the first and BTOpbiM outputs to the control inputs of the first and second keys, respectively, the third output with the control inputs of the third and fourth keys, the fourth output - with the control inputs of the fifth and sixth keys, the outputs of the first, third and fifth keys are connected to the corresponding inputs of the first OR element connected to the X input of the oscilloscope, a single input Y with the output of the second element OR, connected by the first, second and third inputs to the outputs of the VSTROY, fourth and sixth keys, the output of the clock pulse generator is connected to the input of the electronic switch, to the input of the linearly decreasing voltage generator and to the input of the linearly increasing the voltage connected by the output to the information inputs of the first and second keys and to the first output of the first voltage divider connected by the second output to the common bus of the device, the third output to the information The third key input, the linearly mined voltage generator output is connected to the first output of the second voltage divider connected by the second output to the common bus of the device, the third output through the serially connected first collector of the device, the first differential amplifier connected to the information input of the sixth key, the second collector resistor connected to the first output of the first output of the second rheostat, the first and second terminals for connecting For the semiconductor device, a constant voltage source, a third voltage divider, a seventh, eighth, ninth and tenth keys, a second differential amplifier, the first and second pulse voltmeters, and the fifth output of the electronic switch are connected to the control input of the seventh the key connected by the information input to the third output of the first voltage divider, the output to the first input of the third OR element connected by the second input to the output of the eighth key connected by the control input from the pole m output of the electronic switch and with the control inputs of the ninth and tenth keys, information. The first input is with the first output of the third voltage divider connected by the second output to the DC input of the constant voltage source, the third output to the common bus of the connection connected to the first terminal to connect the semiconductor device, the second terminal to connect. Which is connected to the information inputs of the ninth and fifth keys and the second output of the second rheostat connected by the first output to the first input of the first differential amplifier connected by the second input to the second output of the second current resistor and the output of the third element OR, output-. home - with the information input of the tenth key, the first and second inputs of the second differential amplifier are connected respectively with the same terminals of the first collector resistor, output - with the information input of the fourth key, inputs of the first and second pulse voltmeters are connected respectively with the outputs of the ninth and tenth keys.

five

The electronic switch contains a frequency divider connected by an input to an input of an electronic switch and to a first input of a short-circuit trigger connected by a second input to an output of a frequency divider, the output to an input of a delay line connected by first, second, third, fourth and fifth taps, respectively, The first, second, third, fifth, sixth outputs of the electronic commutator connected by the fourth output to the output of the fourth OR element connected by the first and second inputs to the fourth and fifth taps of the delay line wow.

 FIG. 1 shows a diagram of the proposed device; in fig. 2 scheme of the electronic switch; on fig.Z - timing charts of the device; in fig. 4 - time diagrams of the electronic switch; in fig. 5 illustrates an example image of a current-voltage characteristic of a semiconductor device on an oscilloscope screen.

The device (, FIG. 1) contains a generator of 1-pulse pulses, a generator of linearly increasing voltage, a generator of linearly decreasing voltage 3, a constant voltage source 4, a second 5 and first 6 differential amplifiers, an oscilloscope 7, an electronic switch 8, the first - the tenth keys 918, the first 19, the second 20 and the third 21 OR elements, the second 22 and the first 23 klem1 1 for connecting the semiconductor device 24, the first 25 and the second 26 pulsed voltmeters rigidly connected and controlled by the same axis, the first 27 the third 28 and the second 29 resistor e voltage dividers rigidly connected and controlled by one axis, the first 30 and the second

31, rheostats, the first 32 and second. 33 collector rheistor.

The electronic switchboard (FIG. 2) contains a frequency divider 34, an RS flip-flop 35, an e-hold line 36, a fourth element OR 37. The first and second inputs of the electronic switches are connected to the control inputs of the first 9 and second 10 keys, respectively, the third output - with control inputs of the third P and fourth 12 keys, the fourth output with control inputs of the fifth 13 and sixth 14

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keys. The outputs of the first 9, third 11 and fifth I3 keys are connected to the corresponding inputs of the first element OR 19 connected by the output to the input X of the oscilloscope 7 connected by the input Y to the output of the second element I-fflH 20 connected by the first, second and third inputs to the outputs of the second 10, fourth 12 and

sixth 14 keys. The output of the generator 1 clock pulses is connected to the input of the electronic switch 8, to the input of the generator 3 linearly decreasing voltage and to the input of the generator 2 linearly rising voltage connected by the output to the information inputs of the first and second keys and the first output of the first and second keys. the second divider 27 connected to the second output of the common bus device, the third output to the information input of the third KLUCH 11. The output of the generator 3 linearly decreasing voltage is connected to the first output of the second divider 29 connected to the second output of the common bus device, the third output is sequentially connected the first collector resistor 32 and the first rheostat 30 are connected to the common bus of the device, the first differential amplifier 6 connected to the information input of the sixth switch 14, the second collector

a resistor 33 connected to the first output from the first output of the second roostat 3I. The sixth output of the electronic switch 8 is connected to the control input of the seventh key 15 connected by information input to the third output of the first divider 27 output - to the first input of the third element OR 21 connected to the second input to the output of the eighth key 16,

connected by a control input with the sixth output of the electronic comm. 8 and with the control inputs of the ninety seventeen and tenth 18 keys,. the information input - with the first output of the third divider 28, connected with the second output with the output of the DC voltage source 4, the third output - with the common bus of the device connected with the first terminal 23 for connecting the semiconductor device 24, the second terminal 22 for connecting it with the information one. and the entrances of the maidens 17.

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and fifth 13 keys and with the second output of the second rheostat 31, connected by the first output to the first input of the first differential amplifier 6, connected by the second input to the second output of the second current-collecting resistor 33 and to the output of the third element OR 21, the output to the information input of the tenth key 18 The first and second inputs of the second differential amplifier 5 are connected respectively to the same terminals of the first collector resistor 32, the output to the information input of the fourth key 12, the inputs of the first 25 and second 26 pulses voltmeters are connected respectively to the outputs of nineteen seventeen and ten eighth keys.

In the electronic switch 8, the input of the frequency divider 34 is connected to the input of the electronic switch 8 and to the first input of the RS flip-flop 35 connected to the second input to the output of the frequency divider 34, the output to the input of the delay line 36 connected by the first, second, third, fourth and n fifth taps, respectively, with the first, second, third, fifth and sixth outputs of the electronic switch B connected by the fourth output to the fourth element OR 37 connected by the first and second inputs to the fourth and fifth taps of the delay line 36, respectively but

The device works as follows.

The clock pulse generator 1 sets the clock pulses to the inputs of the ramp generator 2 and the generator 3

.. linearly decreasing voltage.

 iio arrival of each sync pulse generators 2. and 3 once form on their own outputs linearly increasing and linearly decreasing saw voltage with amplitude

iM, ax.c, d (. (fig.Z.

At the same time, the clock pulses from generator 1 are distributed by switch 8 to control inputs of keys 9-18.

In the first cycle of operation of the device (Fig. 3), the key 9 is opened, and the linearly increasing voltage from the output of the generator 2 through the key 9 and the element OR 19 is fed to the input X

37

an oscilloscope that causes the X axis to flash on its screen (FIG. 5K. In the second cycle of operation of the device (FIG. 3-), the key 10 and the linearly increasing voltage from the generator 2 output through the key 10 and the OR element 20 is fed to the input Y the oscilloscope 7, -tcr leads to. highlighting on its screen the Y axis (fig.Z.

In the third cycle of operation of the device, the And and 12 keys are opened, while the input X of the oscilloscope 7 through the key 1 1 and the element ШШ 19 receives a linearly increasing voltage from the output of the generator 2, at the input U of the oscilloscope 7 through the key 12 and the element OR 20 - the output voltage of the differential amplifier 5. The output voltage of the differential amplifier 5 is proportional to the voltage drop across the collector resistor. 32, which, in turn, is determined by the current flowing through the rheostat 30 and, therefore, depends on its

resistance and voltage coming from the divider 29. As a result, in the third cycle of operation of the device on the screen of the oscilloscope 7, the load right is highlighted (Fig.5),

the adjustment of the dividers 27 and 29 provides a parallel shift of the load direct on the screen of the oscilloscope 7, by adjusting the rheostat 30 the change of the slope of the load direct.

due to the fact that the axes of the dividers 27 and 29 and the rheostats 30 and 31 are rigidly connected, simultaneously with the change in the parameters of the load direct to

The oscilloscope screen 7 changes the actual load resistance Rj., (rheostat 31) and the supply voltage. (divider 27) semiconductor device 24. Nominal values of resistance Rj, and R., resistors 30 and 31 (among themselves) and resistances, Ige 27 dividers 29, 28 and 27 (among themselves and also current collectors. Resistors 32 and 33 (among themselves ) are chosen equal to ensure that the actual load circuit of the device 24 is identical to the load characteristic displayed on the screen of the non-oscilloscope 7.

In the fourth cycle of operation of the device (Fig. 3), the key 15 is opened, which leads to setting a linearly increasing supply voltage from the generator 2 output through a divider 27. a key 15 and an OR 21 element to the load circuit of the device 24 consisting of a resistor 33 and rheostat 31. The keys 13 and 14 simultaneously open, while the voltage from the output of the differential amplifier 6 proportional to the current through the device 24 enters through the key 14 and the OR element 20 to the input V of the oscilloscope 7. The voltage from terminal 22 is proportional to the voltage on the device 24, comes through key 13 an OR gate 19 to the input of the oscilloscope X 7, which leads to the emission of the current-voltage characteristics of the device 24 and on its screen | (The PID 5).

In the fifth cycle of operation of the device (Fig. 3), the keys 13 and 14 remain in the open state, the key 16 is turned on. At the same time, the constant voltage of the source 4 through the divider 28, the key 16 and the OR element 21 enters the G1) narrow circuit of the device 24, and the inputs X and Y of the oscilloscope 7 receive voltages proportional to the current through the device 24 and the voltage on the device 24 at the operating point. As a result, on the screen of the oscilloscope 7, the operating point of the device 24 is illuminated (FIG. 5) and the exact position of the intersection of its load and current-voltage characteristics is recorded. At the same time, in the fifth cycle of operation of the device, the keys 17 and 18 are opened, with the pulse voltages and the current and voltage at the working point of the device 24 being measured by the pulse voltmeters 26 and 25, respectively.

The electronic switch 8 operates as follows. FIG. 2).

The sequence of clock pulses (signals) from the output of the generator 1 is fed to the input of the frequency divider 34 (figure 4). At the third output of the divider 34, a pulsed signal with a pulse frequency of 5 times shorter than the clock one is formed (FIG. 4), the RS flip-flop 35 forms a sequence of pulses with a duration equal to the duration so. This sequence of pulses is fed to the input of a multi-tap discrete delay line 36, at the first tap of which pulses occur in the same time intervals as at its input. From the 1st, 2nd, 3rd and 4th taps of the delay line 36, the time-shifted control signals arrive at the control inputs of the keys 9 (1st tap), 10 (2nd tap), 11 (3rd tap), respectively 15 (4th finger), 16 17 and 18 (5th finger J.) This ensures that the device is synchronized in time for 1, 2, 3 and 4 cycles. Control signals for keys 13 and 14, which are in accordance with with the operation algorithm, the devices should be included in the second and fifth steps of its operation, are formed at the output of the element OR 37.

Thus, by inserting the key 16, the element OR 21, the source of the constant voltage 4, the divider 28 provides the ability to illuminate the operating point of the device 24 on the oscilloscope screen, which allows an accurate objective specification of the operating point and subsequent precise measurement of its coordinates. using voltmeters 25 and 26, which significantly improves the accuracy of the device.

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Claims (2)

1. DEVICE FOR VISUAL INDICATION OF CHARACTERISTICS OF SEMICONDUCTOR DEVICES, containing an electronic switch connected to the first and second outputs with the control inputs of the first and second keys, respectively, the third output with the control inputs of the third and fourth keys, the fourth output with the control inputs of the fifth and sixth keys' , the outputs of the first, third, and fifth keys are connected to the corresponding inputs of the first OR element, connected by the output to the input X of the oscilloscope, connected by the input Y to the output of the second about an OR element connected by the first, second and third inputs to the outputs of the second, fourth and sixth keys, the output of the clock generator is connected to the input of the electronic switch, to the input of the linearly decreasing voltage generator and to the input of the ramp generator connected an output with information inputs of the first and second keys and with the first output of the first voltage divider connected by the second output to the device common bus, the third output - with the information input of the third key, you A linearly decreasing voltage generator is connected to the first terminal of the second voltage divider connected to the second terminal of the device with a common terminal, the third terminal through the first collector resistor and the first rheostat connected in series with the device’s common bus, the first differential amplifier connected to the information input of the sixth key , a second collector resistor connected by a first terminal to a first terminal of a second rheostat, a first and G second terminals for connecting a semiconductor device, from ichayuscheesya in that, in order to increase the accuracy of the devices has introduced a DC voltage zheniya, the third voltage divider. the seventh, eighth, ninth and tenth keys, the second differential amplifier, the first and second pulse voltmeters, the fifth output of the electronic switch connected to the control input of the seventh., the key connected by the information input to the third output of the first voltage divider, the output to the first input of the third element OR connected by a second input to the eighth key output, connected by a control input to the sixth output of the electronic switch, and to the control inputs of the ninth tenth key, information input 2- ohm first terminal of the third voltage divider connected with the second terminal of the output isSU .... L64637 I 164637 DC voltage point, the third terminal - with a common bus device connected to the first terminal for connecting a semiconductor device, the second terminal for connecting which is connected to the information inputs of the ninth and fifth keys and with the second terminal of the second rheostat connected to the first terminal with the first input of the first a differential amplifier connected by a second input to the second terminal of the second collector resistor and with the output of the third OR element, the output with the information input of the tenth key, the first second inputs of the second differential amplifier are connected respectively to the like outputs of the first collector resistor, the output - to an information input of the fourth key inputs of the first and second pulse voltmeters are connected respectively to the outputs of the ninth and tenth switches. 2. The device according to π.1, wherein the electronic switchboard contains a frequency divider connected by an input to the input of the electronic switch and with the first input of the RS-flip-flop connected to the second input with the output of the frequency divider, and the output with the input a delay line connected by the first, second, third, fourth and fifth taps, respectively, with the first, second, third, fifth and sixth outputs of an electronic switch connected to the fourth output with the output of the fourth OR element, connected by the first and second inputs to the fourth and yatym tapped delay lines respectively.