SU558231A1 - Measuring module for current transfer coefficient of transistors in pulsed mode - Google Patents

Description

one

The invention relates to the field of measurement technology and can be used in measuring instruments - classifiers in measuring and classifying transistors according to the value of the limiting frequency of the gain.

An automatic transistor gain meter in a pulsed mode is known, comprising a mode setting unit, an indicator, an on-amplifier, and a reversible counter. The disadvantage of this meter is the inability to measure at high frequencies 1.

A meter is also known that permits measurements of the gain of high-power transistors at high frequencies and contains an RF generator, a pulse current generator, an oscilloscope to compare base-collector RF currents, and a source of collector voltage 2.

The disadvantages of this meter are low labor productivity, since the current and the collector voltage when changing the next transistor are set manually, and for each measurement it is necessary to compare the base and collector high frequency currents and calculate the gain value.

The aim of the invention is to increase productivity.

This is achieved by the fact that the automatic base current regulator and a resistor are additionally introduced into the meter, and the source of the collector voltage is made in BH.ie of the regulator, whose output is connected directly to the first input of the base current controller and through the transistor and the second input of the base current controller, the third input of which is connected to the output of the pulse generator, for example.

from the reference source

voltage, key, output - with the base of the generating generator, and the transistor being tested.

The drawing shows

scheme of the proposed meter.

The meter contains the reference source

voltage 1, switch 2, current controller of base 3, master oscillator 4, high frequency generator 5, resistor 6, resonant circuit consisting of capacitor 7 and inductance 8, voltage regulator 9, high frequency signal meter 10 , terminals for connecting the base 11, the collector 12, the emitter 13 of the transistor 14 under test.

The meter works as follows.

When a clock pulse from the master oscillator 4 is applied, current regulator 3 through switch 2 connects to the reference terminal 1 and stabilizes the collector current of the tested transistor by changing the base current determined by the voltage difference between the source voltage and the voltage A voltage across the resistor 6. The voltage stabilizer 9 maintains a constant voltage across the junction-to-junction transition by connecting its input directly to the collector emitter terminals of the transistor under test. A signal proportional to the current on the inductance 8 is recorded by an RF-10 meter. The parameter value is defined as the ratio of the RF on the inductance 8 with the transistor included in the circuit to the current on the same inductance with shorted terminals the collector is the base without the transistor, during the calibration of the meter.

The application of the proposed device allows to increase the measurement performance.

Claims (2)

1. USSR author's certificate No. 331342, M. Kl.2 G 01R 31/26, 17.08.70. 2. Pitzalis O. Transistor gain meter. Electronics, 1968, No. 8, p. 15-16 (prototype).