Precision-one-shot

  
If you need a wide-range, resistor-programmable monostable multivibrator, you can program tbe circuit for pulse widths from 1 JlS to 10s-107:1 range. A high-to-low transition at tbe input causes IC1`s output to switch low, thereby turning off Q1 and Q2. With tbe latter transistor turned off, IC3`s output increases and tbe output ofIC2 begins to ramp toward tbe negative supply level at a rate determined by the 0.01-JlF capacitor and tbe programming resistor.
Precision-one-shot - schematic

When IC2"s output voltagereaches -5 V, IC3"s output switches low. Ifyou anticipate input pulses shorter than tbe desired output pulses, Q3 is necessary. This transistor keeps IC1s input low while an output pulse is present, thereby preventing inadvertent resetting of tbe one shot.




Leave Comment

characters left:

New Circuits

.