Design a circuit to provide 60 W at 50 V to a resistive lamp from an AC supply of 120 V ± 10% at 60 Hz. The circuit should be energy efficient—that is, it should consume the least power possible.
Design a circuit to charge a 2-µF capacitor from a DC supply of 24 V. The charging current should be limited to 1 mA. The accuracy should be better than 5%.
The input and output voltages of an amplifier are Find the magnitude and phase of the voltage gain of the amplifier.
An n-channel MOSFET has Kp 20 mA/V2 and Vt = 1.5 V. If the gate–source voltage is VGS = 3 V, find the small-signal transconductance gm of the MOSFET.
An n-channel JFET has IDSS= 20 mA and Vp = 23 V. If the gate–source voltage is VGS = -1.5 V, find the small-signal transconductance gm of the JFET. Assume the devices are in saturation.
The base current of a bipolar transistor is iB 2 (1 + sin 2000 πt) mA and the current gain of the transistor is βF 100. What are IB, ib, IC, and ic?
For a bipolar transistor, the collector–emitter voltages are VCE 6 V and vce = – 100 sin (2000 πt) mV, and the base–emitter voltages are VBE = 0.7 V and vbe = 1 sin (2000 πt) mV. a. What are the expressions for vCE and vBE? b. Find the small-signal voltage gain Av.
For an FET, the drain–source voltages are VDS 6 V and vds = – 50 sin (1000 πt) mV, and the gate–source voltages are VGS = 3 V and vgs 2 sin (1000πt) mV. a. What are the expressions for vDS and vGS? b. Find the small-signal voltage gain Av.
What is the purpose of DC biasing of an amplifier?
What is the effect of rise time on the frequency response of an amplifier?