4.91 An LED is forward-biased by a 3-V battery through a resistor. Find the resistor value required to sustain (a) 10 mA through a green LED at 2.2 V forward voltage drop. (b) 10 mA through a red LED at 1.8 V ...
electricalstudent Latest Questions
4.90 A reverse-biased photodiode is specified to have a dark current of 100 pA and a responsivity of 0.5 A/W. It is connected to the transresistance amplifier shown in Fig. P4.90. Assume an ideal op amp. (a) What is the ...
4.89 A varactor has Cj0 = 150 fF at zero bias, V0 = 3V, and m = 3. Find the range of bias voltages required to vary its capacitance from 80 fF to 20 fF. 0.70 V < VR < 2.87 ...
*4.88 For the circuits in Fig. P4.88, each utilizing an ideal diode (or diodes), sketch the output for the input shown. Label the most positive and most negative output levels. Assume CR ≫ T.
4.87 The clamped capacitor in Fig. P4.87 is loaded by the resistor R. The input vI is a symmetric 10-V peak-to-peak square wave at 100 kHz. Sketch the waveform at vO if the time constant CR = 10 µs.
4.86 A clamped capacitor using an ideal diode with cathode grounded is supplied with a sine wave of 5-V rms. What is the average (dc) value of the resulting output? −7.07 V
*4.85 The following amplitude-modulated signal is applied to the precision rectifier circuit in Fig. P4.85.
4.84 The op amp in the circuit of Fig. P4.84 is ideal with output saturation levels of ±12 V. The diodes exhibit a constant 0.7-V drop when conducting. Find v−, vA, and vO for: (a)vI = +1V (b)vI = +3V (c)vI = −1V (d)vI ...
4.83 The op amp in the precision rectifier circuit of Fig. P4.83 is ideal with output saturation levels of ±13 V. Assume that when conducting, the diode exhibits a constant voltage drop of 0.7 V. Find v−, vO, and vA ...
D *4.82 Consider the circuit in Fig. P4.74 with two equal filter capacitors placed across the load resistors R. Assume that the diodes available exhibit a 0.7-V drop when conducting. Design the circuit to provide ±12-V dc output voltages with ...