Posted on Mar 3, 2013

The input voltage, V1, causes C1 to charge and produce a ramp voltage at the output of the 741 op amp. Diodes D1 and D2 are four-layer devices. When the voltage across C1 reaches the breakover voltage of either diode, the diode conducts to discharge C1 rapidly and the op amp output goes abruptly to zero. This rapid discharge action applies a narrow pulse to G1 and G2. Positive discharge pulses produced by a positive V1 are coupled to the output only through G1, while negative pulses are coupled only through G2.

Click here to download the full size of the above Circuit.

Because of the forward breakover current of diodes D1 and D2, the circuit won"t operate below a minimum input voltage. An increase of R1 increases this minimum voltage and reduces the circuit"s dynamic range. The minimum input voltage with R1 at 1 Kn is in the range of 10 to 50 m V. This input dead zone, when input signal V1 is near zero is desirable in applications that require a signal to exceed a certain level before an output is generated.

Leave Comment

characters left:

New Circuits



Popular Circuits

White LED Drive Circuit
Audio peak Indicator
Ac-To-Dc Converter
Servicing the Hammond B-3 Type Pre-Amp
Phoenix From Start to End
car cam
motor controller
4081 AND gates
Three circuits of preamp tone controls by NE5532
CF1 CF2 main circuit