OUT_OF_BOUNDS_PULSE_WIDTH_DETECTOR

Published:2009/7/6 2:24:00 Author:May | From:SeekIC

Requiring only two ICs to monitor a train of positive pulses, this circuit produces a single positive output pulse for each input pulse whose duration is either too long or too short. You specify the minimum and maximum limits by adjusting the trimming potentiometers, R1 and R2. You can set the value of the acceptable pulse width from approximately 50 ns to 10 μs, for a 74123 monostable multivibrator. The leading edge of an input pulse triggers one shots ICIA and ICIB as you can see from the timing diagram. Each NAND-gate output is high unless either or both inputs are low, so outputs X and Y are high unless the circuit encounters an out-of-range pulse. IC2D then gates a negative pulse from IC2B or IC2C to produce the circuit's positive output pulse.



Reprinted Url Of This Article:
http://www.seekic.com/circuit_diagram/Measuring_and_Test_Circuit/OUT_OF_BOUNDS_PULSE_WIDTH_DETECTOR.html

Print this Page | Comments | Reading(3)