zener diode
2013-10-12 2:20 am
Given that the zener voltage VZ = 8.2V, with the condition that the zener current 75mA ≤ iZ ≤ 1A and the load resistance RL = 9Ω. Calculate resistance RS so that load voltage VL is regulated to 8.2V while the input voltage Vin varies by ±10% from its nominal value of 12V. Also check that the zener current iZ is larger than 75mA at lowest input voltage Vin .
回答 (2)
2013-10-12 8:42 am
✔ 最佳答案
Let the structure be :V⁺ ---- R ----- X ------ GNDX is Capacitor // zener diode // 9Ω Load
Voltage across load is stabilized to 8.2V
Current of the 9Ω Load = 8.2/9 = 0.9111A
Lowest V⁺ = (12)(1 - 0.1) = 10.8 V
Current through R = 0.9111 + 0.075 = 0.986 A
Voltage across R = 10.8 - 8.2 = 2.6 V
R = 2.6 / 0.986 = 2.6 Ω
2013-10-12 12:51:32 補充：
V⁺ ---- R ----- X ------ GND ... X is Capacitor // zener diode // 9Ω Load
Current of the 9Ω Load = 8.2/9 = 0.9111A
Current through zener diode = 0.075A
Current through R = 0.9111 + 0.075 = 0.986 A
2013-10-12 6:06 pm
so the zener current larger than 75mA is 0.986A?
收錄日期: 2021-04-27 20:37:55
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https://hk.answers.yahoo.com/question/index?qid=20131011000051KK00136