1 of 15

For the half wave rectifier shown, where v_I = 120 V_rms, and R = 50 Ω.

Assume Vγ = 0.6 V.

Sketch the output voltage, v_o
Calculate the power dissipated by the resistor, R

Answers:�i) Peak output voltage is 41.83 V�ii) 35 W

2 of 15

A half-wave rectifier is used to supply a 5 V peak output voltage to a resistive load of 800 Ω.

The diode has a turn on voltage of Vγ = 0.7 V and a resistance, r_fof 25 Ω.

Calculate the value of the input voltage, v_S( represent your answer as a sine wave)
Determine the duty cycle of the rectifier circuit
Calculate the maximum reverse bias voltage for the diode

Answers:�i) v_s = 5.86 sin ωt�ii) 46.2 %

iii) 5.86 V

3 of 15

For a half-wave rectifier circuit, the output voltage across a 2 kΩ load resistor is 30.72 V. The diode has a turn on voltage of Vγ = 0.7 V.

Obtain the number of turns ratio in the primary and secondary of the transformer given that v_p = 220 V (rms)
Calculate the peak inverse voltage of the diode

Answers:�i) 10:1

ii) 31.42 V

4 of 15

A full-wave center tapped rectifier uses two diodes, the internal resistance of each diode may be assumed to be constant at 20 Ω with Vγ = 0.65 V . The transformer’s rms secondary voltage is 50 V and load resistance is 980 Ω.

Find the peak value of the load current.
Determine the duty cycle of the rectifier circuit

Answers:�i) 70 mA�ii) 99.4 %

5 of 15

A full-wave rectifier circuit uses diodes, with Vγ = 0.65 V . The transformer’s rms primary voltage is 220 V and turns ratio, N₁:N₂ = 20:1.

What is the peak value of the output current if R = 1.5 kΩ ?
What is the Peak Inverse Voltage (PIV) rating of each diode?

Answers:�i) 9.94 mA�ii) 30.46 V

6 of 15

In the bridge rectifier circuit shown above, the diodes are assumed have a turn on voltage of Vγ = 0.7 V. The primary to secondary turns ratio is given as 4:1. Find

peak output voltage
peak inverse voltage (PIV)

(rms)

Answers:�i) V_opeak = 80 V�ii) 80.6 V

7 of 15

A bridge rectifier circuit with a filter capacitor has R_L = 0.1 kΩ. The secondary transformer delivers an input voltage, v_sof 15 V (rms) and has a frequency of 60 Hz. Assume that the diodes have turn-on voltage of 0.7 V each.

Calculate the value of the diode current, I_D
What will the value of the filter capacitor C, so that the ripple voltage is limited to 500 mV?

AC Line

Voltage

Answers:�i) 198.13 mA�ii) 3.3 mF

8 of 15

Answer:�15.5 ≈ 16:1

9 of 15

A full-wave bridge rectifier circuit with a capacitor filter is designed to meet the following specifications

transformer input AC voltage, v_s = 9.3 V (rms)
Peak value of load current: 0.5 mA
Maximum ripple: 0.2 V peak-to-peak

If the transformer input AC voltage, v_p is 120 V (rms) at 60 Hz

turns ratio required for the transformer
peak rectifier output voltage,
determine the value of R_Land the capacitor

Assume that the diodes has the turn on voltage of 0.7 V and r_f = 10 Ω

N₁: N₂

V_O

v_P

v_s

Answers:�i) 13:1

ii) 11.74 V�iii) 23.48 kΩ and C = 20.83 μF

10 of 15

Answers:�i) I_Z = 0.088 A, I_L = 0 A, V_L= V_Z = 5.6 V�ii) I_Z = 0.1656 A, I_L = 0.0224 A, V_L= V_Z = 5.6 V

11 of 15

Consider the circuit shown below. The Zener diode voltage is V_Z = 3.9 V

Determine I_Z , I_L , and the power dissipated in the diode

Answers:�I_Z = 0.367 mA, I_L = 0.975 mA,

P_Z = 1.43 mW

12 of 15

A 5.0 V stabilized output voltage, V_Lis required to be produced across a 0.2 kΩ load from a 12 V DC power supply input source. The maximum power rating P_Z of the Zener diode is 2 W. Using the voltage regulator circuit, if the Zener diode is dissipating the maximum power calculate:

The current flowing through the Zener diode.
The value of R_i

Answers:�i) I_Z = 0.4 A�ii) R_i = 16.47 ohm

13 of 15

A voltage regulator circuit is shown below where a 10 V Zener diode is connected across a 1 kΩ load. The input voltage source V_PS = 18 V and a series resistor R_i is connected to limit the Zener diode current.

Determine the value of R_i required to make the current I_Z = 20 mA.

Answer: R_i = 266.67 ohm

14 of 15

Design the voltage regulator circuit illustrated below using the specifications given

V_L = 3.3 V
Input source, V_PS variation is 6 V to 10 V
Output load variation, R_L = 2 kΩ to 4 kΩ

Answer: R_i = 1.3 k-ohm

15 of 15

Determine the value of R_i for the voltage regulator circuit illustrated below using the specifications given

V_Z = 10 V
Input source, V_PS variation is 15 V to 20 V
Load current variation, I_L = 50 mA to 500 mA

Assume I_Z (min) = 0.1 I_Z (max).

Determine the power rating required for the Zener diode

Answers:

R_i = 8.08 Ω

P_Z = 11.9 W