SU828383A1 - Pulse burst generator - Google Patents

Description

for a short duration, elements 1 and 2 are closed and the capacitors 7 begin to charge, but since the capacitance of the capacitor 7 of element 4 is many times greater than the capacity of the capacitor 7 of element 5, it is charged earlier to the response level of the Schmitt trigger 6 of element 4 (trigger thresholds Schmitt 6 and elements 4 and 5 are the same), which goes into another state and opens element 1 with its output signal, which will cause the discharge of capacitor 7 of element 4 to the level of the second trigger threshold of the Schmitt trigger of the same element Tc in the initial state, while closing element 1, and this process will be repeated until the voltage on the capacitor 7 of element 5 reaches the level of the trigger threshold of Schmitt trigger 6 of element 5, which after operation opens element 4, where its inverse output will set the logical level "O. After the logical output "O" is also established at the reverse output of element 1, both setting triggers will return to their initial state, when the output of element 3 sets the logical level "1. With the arrival of the next clock pulse on bus 8, the described process will repeat, i.e., one generator clock will send one burst of pulses on output bus 9, in which the first and last, as well as all the others in the packet, will be without distortion.

In the case of supplying a constant potential to bus 8, a logic level “1 generator will operate in continuous mode (without packs).

The generator is implemented on ECL logic series 500. The generator is reliable in operation; changing the value of the emitter resistors

(which in this series are set externally to the IC), it is possible to change both the duration of the pulses themselves and the duration of the packs within very wide limits (the maximum pulse frequency in the pack reaches 200 Mg, and the maximum duration of the pack can be up to a few seconds). The proposed generator has

This is one advantage over known generators: in the case that wire elements OR flip-flops are connected to the Schmitt trigger outputs, it is possible at any moment to terminate the formation as

the duration of the pulse, and the duration of the burst.

Claims (2)

Invention Formula Pulse generator, containing a delayed feedback element made, for example, on a Schmitt trigger with an input capacitor that is connected between the first input and the direct output of the first OR / NOT-OR element, the second OR / NOT-OR element, the three-input NOT-OR element, which interconnected with cross-feedbacks, according to a trigger scheme with the first and second OR / NOT-OR elements, characterized in that, in order to form bursts of pulses with variable parameters, a delayed feedback element is additionally introduced into it, which is connected between the second input and the forward output of the second element OR / NOT-OR. Sources of information taken into account in the examination 1. "Electronic Engineering, november, 1972, p. 78 2. Antanyuk, V.P., et al. A simple geierator of pulse packets. - Exchange of experience in the radio industry. № 1, 1976, p. 54.