A pulse is applied to the RL integrator in Figure 20-36. Determine the complete wave-shapes and the values for I, V_{R}, and V_{L}.
A pulse is applied to the RL integrator in Figure 20-36. Determine the complete wave-shapes and the values for I, V_{R}, and V_{L}.
The circuit time constant is
\tau = \frac{L}{R}= \frac{5 \ mH}{1.5 \ k\Omega }= 3.33 \ \mu sSince 5\tau= 16.7 \ \mu s is less than t_{W}. the current will reach its maximum value and remain there until the end of the pulse. At the rising edge of the pulse,
i= 0A
v_{R}= 0 V
v_{L}= 10 V
The inductor initially appears as an open, so all of the input voltage appears across L During the pulse,
i increases exponentially to \frac{V_{p}}{R}= \frac{10 \ V}{1.5 \ k\Omega }= 6.67 \ mA in 16.7 \ \mu s
v_{R} increases exponentially to 10 V in 16.7 \ \mu s
v_{L}decreases exponentially to zero in 16.7 \ \mu s
At the falling edge of the pulse,
i = 6.67 mA
v_{R} = 10V
v_{L} = -10 V
After the pulse,
i decreases exponentially to zero in 16.7 \ \mu s
v_{R} decreases exponentially to zero in 16.7 \ \mu s
v_{L} increases exponentially to zero in 16.7 \ \mu s
The waveforms are shown in Figure 20-37