Design square wave generator using opamp to have output voltage $=\pm 5$ volts, frequency $1 \mathrm{khz}$, with $70 \%$ duty cycle? Assume $\mathrm{VCC}=\pm 12$ volts.

Solution:

$ \begin{aligned} &F=1 \mathrm{KHz}_2 \text { duty cycle }=70 \%, \quad \mathrm{VO} \pm 5 \mathrm{~V} \\ &+\mathrm{Vsat}=12 \mathrm{~V},-\mathrm{Vsat}=-12 \mathrm{~V}, \ldots \text { (given) } \end{aligned}\\ $

Assume $R_1=R_2=10 \mathrm{~K}-2$

When $v_0=+5 v$ then ' C ' charges through $R_3$ via $D_1$ when $v o=-5 v$ then ' C' discharges …