GATE 2015 EE – SET 2 – Question 39

Solution :

Astable po-amp multivibrator

Always produces a square wave .

$$\beta $$ =$$ \frac{R_{2}}{R_{1}+R_{2}} $$ = $$\frac{2}{2+2}$$
$$\beta$$ = 0.5

T = 2RCln$$\left [ \frac{1+\beta }{1-\beta } \right ]$$

T = 2 * 1 * $$10^{3}$$ *0.25 *$$10^{-6}$$ln$$\left [ \frac{1+0.5}{1-0.5} \right ]$$

T =  0.5*$$10^{-3}ln \left [ 3 \right ]$$

T  = 0.5 * $$10^{-3}$$ * 1.098
T  = 0.55 * $$10^{-3}$$

T = 0.55ms