As long as the input voltage to this trigger circuit is less than the lower threshold level, TI is cut off; T2 will be saturated through R2. Consequently, the T2 collector voltage will be low, determined by the T2 saturation voltage (approximately I 00 m V) and the voltage across the positive feedback diode D2. The latter voltage can vary over a limited range as a function of the power supply voltage and the R3 resistance. Both these parameters may be selected between wide limits without upsetting the operation of the circuit.
Downloading of this magazine article is reserved for registered users only.
Discussion (0 comments)