A designer requires a shunt regulator of approximately 20 V. Two kinds of Zener diodes are available: 6.8-V devices with rz of 10 Ω and 5.1-V devices with rz of 30 Ω. For the two major choices possible, find the load regulation. In this calculation neglect the effect of the regulator resistance R.
A. -30mV/mA and 120mV/mA respectively
B. 30mV/mA and 60mV/mA respectively
C. -60mV/mA and +60mV/mA respectively
D. -30mV/mA and -120mV/mA respectively
Answer:D
A designer requires a shunt regulator of approximately 20 V. Two kinds of Zener diodes are available: 6.8-V devices with rz of 10 Ω and 5.1-V devices with rz of 30 Ω. For the two major choices possible, find the load regulation. In this calculation neglect the effect of the regulator resistance R.
A. -30mV/mA and 120mV/mA respectively B. 30mV/mA and 60mV/mA respectively C. -60mV/mA and +60mV/mA respectively D. -30mV/mA and -120mV/mA respectively
Explanation: Three 6.8v zeners provide 3*6.8 = 20.4v with 3 * 10 =30? Resistance, neglecting R, we have