SU1213522A1 - Flip-flop - Google Patents

Abstract

The invention relates to devices that generate an abrupt voltage at the output, as soon as the input voltage exceeds a certain level, and abruptly, which ceases to form when the voltage drops to the level that the trigger returns to its original state. The purpose of the invention is to expand the scope of the trigger by making it possible to maintain the magnitude of the input amplitude at the trigger output when the threshold level at the input is exceeded. In addition, it is possible to operate the trigger without a power source. The trigger contains transistors 1 and 3 of the first conductivity type, transistor 2 of the second conductivity type, resistors 4, 5 and 6, input and output buses 7 and 8, diode 9 and zener diode 10. 2 Il. (L with yu 00 od 10 yu

Description

one

The invention relates to a pulse technique, namely, devices forming a surge voltage at the output, as soon as the voltage at its input exceeds a certain level (threshold), and abruptly stops forming the voltage at the output at a decrease in the voltage input to initial state.

The purpose of the invention is to expand the scope of the application of the trigger by ensuring that the magnitude of the input amplitude at the trigger output is maintained when the threshold level at the input is exceeded, ensuring that the trigger operates without a power source and reducing the trigger hysteresis.

Figure 1 is a schematic diagram of the proposed trigger; FIG. 2 is diagrams of input and output signals explaining the operation of the trigger.

The trigger (Fig, 1) contains the first transistor 1 of the first conductivity type, the second transistor 2 of the second conductivity type, the third transistor 3 of the first conductivity type three resistors 4-6, the input bus 7, the output bus 8, the diode 9 and the zener diode 10.

The emitter of the first transistor 1 is connected to the zero potential bus, the collector through the first resistor 5 is connected to the base of the second transistor 2, the collector of which is connected to the output bus 8 and connected in series through the second resistor 6 and the diode 9 is connected to the collector of the third transistor 3, the emitter of which is connected to the base of the first transistor 1, and the base through the third resistor 4 connected in series and the zener diode 1 is connected to the input bus 7 and the emitter of the second transistor 2.

The job of the trigger is as follows.

When the input voltage is less than the threshold voltage equal to the sum of the voltages of the Zener diode 10 and the voltage drop between the base of the third transistor 3 and the emitter of the first transistor 1 when current flows in the direction of their conduction, transistors 1-3 are locked and trigger 3032

which current from the input voltage source U does not consume.

When Uf is exceeded, the voltage value UQ through the base of the third

5, the emitter of the first transistor 1, the base and the collector of the second transistor 2 will flow, which creates a voltage drop across the load resistance. When

0, this voltage value will exceed the voltage value of the beginning of the conduction of diode 9, a current flows through the collector of the third transistor 3, as a result of which

J5 emitter currents third transistor 3, base current, emitter currents and collector of the first transistor 1, base, emitter and collector of the second transistor 2, which will lead to an increase in current through the diode 9, the second resistor 6 and the collector of the third transistor 3, etc. ., i.e. an avalanche-like process will occur, after which the second transistor 2

25 will enter saturation mode and a voltage will be generated abruptly on the output bus 8, the amplitude of which is approximately equal to the voltage amplitude on the input bus 7.

30 With a further increase in input voltage, the output voltage also increases, i.e. the pulse shape and output amplitude replicates the pulse shape and amplitude I at the input when it exceeds the Ue.

When the input voltage decreases to U, the base currents of transistors 1–3 begin to decrease, which will lead to a decrease in the collector current of the second transistor 2 and the voltage on the bus 8, the current through the diode 9, the second resistor 6 and the collector of the third transistor 3, the currents of the bases of the first and second transistors 1 and 2, etc., which will lead to an avalanche-like process, after which transistors 1–3 will be in active mode and a small current will flow through them, which will create a fall

 the voltage on the load resistance is less than the voltage of the onset of conduction of the diode 9.

With the achievement of the voltage Uft) of a value less than Uo, the current through

5, the zener diode 10 and the base of the transistors 1-3 become zero and the output voltage Ugtrtjt becomes close to zero.

35

45

Since the trigger and release levels of the proposed trigger are determined by the same zener diode 10, the trigger hysteresis is not high.

: F o .rm llu inventions

A trigger containing the first transistor of the first type of conduction; the collector KOTOpoi o is connected via the first resistor to the base of the second transistor of the second conductivity; the collector of which is connected to the output bus; the third transistor of the first conductivity type,

213522. .

hence the connected second resistor and diode, the third resistor and the input bus, which is different with the fact that, in order to expand

5 of the field of application, a zener diode is additionally introduced into it, the emitter of the second transistor is connected to the input bus, and through a series-connected zener diode and a third resistor is connected to the base of the third transistor whose collector is connected via a series-connected second resistor and diode to the output bus ,, emitter

15 is connected to the base of the first transis-. torus, the emitter of which is connected to the BUS of zero potential.

Editor N. Gunko Order 785/60

Compiled by A. Yanov Tehred T. Dubinchak

Corrector

 Circulation 818 Subscription

VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5

Branch PPP Patent, Uzhgorod, st. Project, 4

2.

Proofreader L. Patay

Claims (1)

Claim A trigger containing the first transistor of the first conductivity type, the collector κοτοροΐΌ through the first resistor is connected to the base of the second transistor of the second conductivity type, the collector of which is connected to the output bus, the third transistor of the first conductivity type, 1213522 * therefore connected the second resistor and diode, the third resistor and the input bus characterized by the fact that, in order to expand the scope of application 5, a zener diode is additionally introduced into it, the emitter of the second transistor is connected to the input bus and through A zener diode and a third resistor are connected to the base of the third transistor, the collector of which is connected through a second resistor and a diode in series with the output bus, and the emitter 15 is connected to the base of the first transistor. torus, the emitter of which is connected to the bus of zero potential. Compiled by A, Yanov Editor N. Gunko Tehred T. Dubinchak Proofreader L. Patay Order 785/60 9 Circulation 818 Subscription VNIIIPI of the USSR State Committee for Inventions and Discoveries 113035, Moscow, Zh-35, Raushskaya nab., D. 4/5 Branch of PPP Patent ”, Uzhhorod, st. Project, 4