Answer Happy

1. Analyze the following circuit. Calculate the capacitor voltage as a function of time for 5V step input. (R=1k, C=200nF). Assume initial capacitor voltage is zero. R w + + vs(t) RS vc (1) 2. Verify your calculations using SPICE. 3. Read the data sheet of LM555 timer circuit. Using the timer IC, build a circuit that will blink an LED continuously with 1 sec time period. The LED should be on for 0.5 sec and off for 0.5 sec. For this part do the followings: 1. Search internet, choose an application circuit that will generate square wave oscillation using LM555. Adjust the frequency by properly selecting R and C values. Show your calculations on how you determined the frequency of oscillations. 2. Read the data sheet of typical LEDs. Connect an LED to the output of the timer with a proper bias resistor. Calculate the value of the bias resistor as suggested in the data sheet.