直流电源稳压电路
电路能力测试-2：直流电源稳压电路
circuit knowledge test-2: dc-dc ldo regulator
what will be the dc voltage at pin-1 of ic lm7805?
what will be the supply current for dv 5v regulated output on this drawing?
if 78m05 with dpak package dissipation 60°c/w, then what surface temperature will be for ic 78m05 at 25°c room temperature?
same condition as the question-3: if dc 5v output will supply 150 ma for all circuits, what surface temperature will be for ic 78m05 at 25°c room temperature?
what minimum input voltage will be allowed for 5v stabilized output if the minimum dropout voltage for lm78m05 is 1.5 volt?
what will be the suitable resistance value and power rating of rp92 & rp93 for lowest lm78m05 surface temperature theoretically at 100 ma supply current and 10 volt low line input?
试题解答
circuit knowledge test-2: dc-dc ldo regulator
ans-1:
vin = 12 – 34 * 0.084 = 12 – 2.86 = 9.14 volt.
ans-2:
same as the input current 84 ma.
ans-3:
power loss = (9.14 – 5.0) * 0.084 = 0.35 w. then tht = 0.35 * 60 = 21 °c
final junction temperature tj = 25 + 21 = 46 °c
ans-4:
vin = 12 – 34 * 0.15 = 6.9 volt.
power loss = (6.9 – 5.0) * 0.15 = 0.285 w. then tht = 0.285 * 60 = 17 °c
final junction temperature tj = 25 + 17 = 42 °c
ans-5:
vmin = 34 * 0.084 + 1.5 + 5.0 = 9.36 volt.
ans-6:
vdrop = 10 – 5.0 – 1.5 = 3.5 then r = 3.5/0.1 = 35 ohm.
rp92 = rp93 = 68 ohm.
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circuit knowledge test-2: dc-dc ldo regulator
what will be the dc voltage at pin-1 of ic lm7805?
what will be the supply current for dv 5v regulated output on this drawing?
if 78m05 with dpak package dissipation 60°c/w, then what surface temperature will be for ic 78m05 at 25°c room temperature?
same condition as the question-3: if dc 5v output will supply 150 ma for all circuits, what surface temperature will be for ic 78m05 at 25°c room temperature?
what minimum input voltage will be allowed for 5v stabilized output if the minimum dropout voltage for lm78m05 is 1.5 volt?
what will be the suitable resistance value and power rating of rp92 & rp93 for lowest lm78m05 surface temperature theoretically at 100 ma supply current and 10 volt low line input?
试题解答
circuit knowledge test-2: dc-dc ldo regulator
ans-1:
vin = 12 – 34 * 0.084 = 12 – 2.86 = 9.14 volt.
ans-2:
same as the input current 84 ma.
ans-3:
power loss = (9.14 – 5.0) * 0.084 = 0.35 w. then tht = 0.35 * 60 = 21 °c
final junction temperature tj = 25 + 21 = 46 °c
ans-4:
vin = 12 – 34 * 0.15 = 6.9 volt.
power loss = (6.9 – 5.0) * 0.15 = 0.285 w. then tht = 0.285 * 60 = 17 °c
final junction temperature tj = 25 + 17 = 42 °c
ans-5:
vmin = 34 * 0.084 + 1.5 + 5.0 = 9.36 volt.
ans-6:
vdrop = 10 – 5.0 – 1.5 = 3.5 then r = 3.5/0.1 = 35 ohm.
rp92 = rp93 = 68 ohm.
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成为一位成功的人工智能工程师并不意味着需要精通编码
有了华为云大数据BI，企业数字化转型该如何做？
直流电源稳压电路
第6代柔性AMOLED生产线进展良好，京东方与三星、华为合作稳定
OPPO采用Super VOOC闪充技术，重新定义快充
Microchip推出首款集成16位ADC、10 Msps ADC、 DAC、USB和LCD的PIC单片机
如何使用代码发布导航需要的传感器信息
手机电池相关知识介绍
基于单芯片数字波形发生器的频率调节
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随着基础技术的稳步发展 许多不同行业对现场机器人的需求越来越高
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