WorksheetsEOC ELECTRICAL CIRCUIT DEE30043
Total questions: 9
Worksheet time: 7mins
a)Explain diode as wave retifiers in DC power supply by using output voltage waveform at point A ,B ,and C .
(a)
b) With the aid of Colpits Oscillator which given that C1 = 0.5µF and frequency 30kHz, calculate the value of inductor (L),the required Voltage Gain (Av) for oscillation and the Feedback Factor (ꟗ).
L=0.625mH
Av=10
β = 0.1
L=0.955mH
Av=12
β = 0.5
c) Discuss its characteristic of each block of an Op-Amp.
d) An ideal summing op-amp has three input using 100kΩ resistor and a feedback resistor of 50kΩ. Calculate the value of Vo if V1 = 3V, V2 = 4V and V3 = 0.5V2 and compute Common Mode Rejection Ratio (CMRR) value in decibel (dB) if the differential gain for the amplifier is 60 and the common mode gain of 0. 02
CMRR=20 log 3000
dB=69.54 db
CMRR=20 log 3000
dB=59.25db
CMRR=10 log 3000
dB=69.54 db
e) Explain about
Inverting Schmitt Trigger.
(a)
f) Compare TWO (2) differences between Passive Filter and Active Filter .
g) Identify the cut-off frequency, fc and voltage gain, Av of a second – order high – pass active filter for R1 = R2 2.1kΩ, C1 = 0.02µF, C2 = 0.05µF and RG = 25kΩ, RF = 50kΩ.
fc=2.397kHz
Av=3
fc=4.725kHz
Av=5
fc=4.725kHz
Av=2
h) Calculate R2, and R3. Hence, compute V out if given V ref = 4V and Rf = 15kΩ for binary 0001², 0110² and 1111².
R2=40k ohm
R3= 20k ohm
R2=30k ohm
R3=20k ohm
i) ) Calculate the V out when input binary is 0011 and 1111 for R/2R ladder 4-bit DAC with value of R = Rf = 15kΩ and V ref is 3V. Determine Step Size and Percentage of Resolution.
Step size=0.3v
Percentage of resolution=7.52%
Step size=0.2v
Percentage of resolution=6.67%
