A typical switch circuit based on a transistor is shown below in which the load, an...

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A typical switch circuit based on a transistor is shown below in which the load, an LED, is connected on the emitter side of the transistor. Determine the following: a) What is the minimum value of Vin required to keep the transistor saturated? Assume that there is a 0.7 V base-to-emitter voltage drop, a 0.2 V collector-to-emitter voltage drop, a 2.5 V drop for the LED and that beta is 100. V₁. V. (V) in 61 4- 2- 0 -2- -4- ON OFF www LED b) Following the calculation in (a), sketch the LED on-off curve for the circuit given the Vin in the waveform shown. 2 ΚΩ 2 ΚΩ ww 2 IN 2 KQ 3500 。5V LED 5 t(s) 5t(s) A typical switch circuit based on a transistor is shown below in which the load, an LED, is connected on the emitter side of the transistor. Determine the following: a) What is the minimum value of Vin required to keep the transistor saturated? Assume that there is a 0.7 V base-to-emitter voltage drop, a 0.2 V collector-to-emitter voltage drop, a 2.5 V drop for the LED and that beta is 100. V₁. V. (V) in 61 4- 2- 0 -2- -4- ON OFF www LED b) Following the calculation in (a), sketch the LED on-off curve for the circuit given the Vin in the waveform shown. 2 ΚΩ 2 ΚΩ ww 2 IN 2 KQ 3500 。5V LED 5 t(s) 5t(s)