SU1653134A1 - Pulse generator - Google Patents

Abstract

The invention relates to a pulsed technique, in particular, to an optoelectronic microsecond generator, and solves the problem of constructing an o-reactive optoelectronic pulse generator for operation in standby and self-oscillatory modes. The purpose of the invention is to simplify the generator, expanding the range of adjustment of the pulse frequency and the field of application by providing operation in the selective one-oscillator mode. This is achieved by building a generator based on a bispin-optocoupler 5, a transistor 4 interrupting the optical connection between a bispin-photodetector 6 and a light-emitting diode 7, a bispin-optocoupler 5 during a pulse generator operating time on a load, a bispin-photodetector 6. LED 7 is shunted by an open transistor 4 that inverts the output of the generator. 1 il. (L

Description

The invention relates to pulsed technology, and in particular, to pulse generators of the microsecond range and can be used in automation devices.

The aim of the invention is to simplify the generator, expanding the range of adjustment of the pulse repetition rate and its scope. jq

The drawing shows a diagram of the generator.

! The generator contains the first 1, second 2 and third 3 resistors, a transistor 4 and a bispin optocoupler 5j consisting of 15 bispin photodetectors 6 and LED 7, as well as a power bus 8 and a signal bus 9 of the device. Emitter. transistor 4 is connected to a common bus of the device; the base of transistor 4 is connected through the first resistor to the output of the locking contact of the photodetector 6, the output of the ohmic contact of which is connected to the power bus, the cathode of LED 7 is connected to the common bus, and the 25 anode> to the collector of transistor 4 directly and through a variable resistor 3 bus 9. Resistor 2 is connected between the terminals of the base and emitter • Transistor 4. 30

The generator works as follows.

When working in standby mode, a supply voltage (positive potential) is supplied to the power bus 8, and pulses (signals) of positive polarity are supplied to the sigal bus 9. In the pause between pulses, the current through the LED 7 does not flow, the photodetector b is not irradiated and is in a non-conductive state, so the transistor 4 is closed. Upon receipt of a pulse on the bus 9, the flow of current begins. through LED 7 and irradiation of the photodetector 6. If the pulse duration: 'pa does not exceed the duration of the on-delay (turn-on) of the photodetector 6, then it does not switch. Otherwise, on the resistors 1 and 2 of the load, a differential (front) ^ 0 .- of a positive polarity voltage is allocated, the transistor 4 opens and shunts the LED 7, the radiation of the photodetector 6 stops. Despite the cessation of irradiation, the photodetector 6 pro ^ 5 must be in a conductive co; melting for some time, determined by the properties of its structure. After the end of the pulse generation, photodetector. the capacitor 6 goes into a non-conductive state and the transistor 4 closes; this state of the generator is maintained until the next pulse arrives.

The amount of delay in turning on the photodetector 6 is determined by the properties * of its structure, the properties of the optocoupler 5 (current transfer coefficient) and the circuit parameters (LED current 7). As the LED current increases, the delay duration decreases. The control of the delay time of the output pulse of the generator can be performed using a resistor 3 or by changing the amplitude of the pulses on the bus 9. The duration of the pulse of the generator increases slightly with decreasing current of the LED 7.

When a long signal (or pulse) is applied to bus 9, a pulse pulse is allocated at the generator output (resistor 1), and its duration can exceed the signal duration by no more than the duration of one generator pulse.

When applying to the bus 9 constant voltage, the generator operates in self-oscillating mode. At the same time, pulses of negative polarity with an amplitude of approximately 1.2 V are allocated on the collector of transistor 4. In practice, it is sufficient to combine buses 8 and 9 to transfer the generator into self-oscillating mode.

Claims (1)

Claim A pulse generator comprising a power bus, a signal and common bus, a transistor connected by an emitter to a common bus, first and second resistors, the first terminals of which are connected respectively to the base and emitter of the transistor, characterized in that, in order to simplify, expand the frequency adjustment range following the pulses and the scope by providing operation in a selective single-vibrator mode, a variable resistor and a bispin optocoupler are introduced into it, and the bispin photodetector of the bispin optocoupler is connected with an ohmic output Here, contacts to the power bus and terminal locking contact - to the second terminal of the first resistor, the LED-optocoupler connected bispin cathode 1653 (34 to the common bus, and the anode to the collector of the transistor and the first output of the variable resistor, the second output of which is connected to the signal bus, and the second output of the second resistor to the base of the transistor.