Question 3 (IEIIQ16)
A 3 W rated Zener diode is used in a shunt voltage regulator circuit to supply a dc output of 12 V to a variable load with a minimum resistance of 240 Ω. The supply voltage varies between 20 V and 24 V.
3.1 Draw the circuit diagram.
3.2 Calculate the range of series resistance that may safely be used in this circuit. Select a single suitable standard value.
3.3 Calculate the maximum power rating required for the series resistor.
Question 4 (IEIIQ17)
A simple Zener voltage regulator is required to provide a steady regulated output voltage of 10 V under a maximum load of 80 mA, while the input voltage to the regulator varies between 12 V and 14 V.
17.1 Calculate the maximum rated current value of a Zener diode to be used
17.2 Calculate the minimum power for the Zener that could be used safely.
17.3 If a 5 W rated Zener were to be used in this circuit:
(i) Calculate the maximum rated current value of a Zener device to be used
(ii) Calculate the range of possible RS. limiting resistor values.
(iii) Suggest a suitable standard E12 resistor value
Question 3 (IEIIQ16)
A 3 W rated Zener diode is used in a shunt voltage regulator circuit to supply a dc output of 12 V to a variable load with a minimum resistance of 240 Ω. The supply voltage varies between 20 V and 24 V.
3.1 Draw the circuit diagram.
3.2 Calculate the range of series resistance that may safely be used in this circuit. Select a single suitable standard value.
3.3 Calculate the maximum power rating required for the series resistor.
Question 4 (IEIIQ17)
A simple Zener voltage regulator is required to provide a steady regulated output voltage of 10 V under a maximum load of 80 mA, while the input voltage to the regulator varies between 12 V and 14 V.
17.1 Calculate the maximum rated current value of a Zener diode to be used
17.2 Calculate the minimum power for the Zener that could be used safely.
17.3 If a 5 W rated Zener were to be used in this circuit:
(i) Calculate the maximum rated current value of a Zener device to be used
(ii) Calculate the range of possible RS. limiting resistor values.
(iii) Suggest a suitable standard E12 resistor value
