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18 ཥɿཥ༩ྼ୦
(̬) ཥ౺කᗫʘᏐ͜ķLED ᚨਗཥ༩
ཥ౺කᗫᏐ͜ί೯Έɚ(LED)ᚨਗཥ༩dνྡ 2-3 הͪdՉ
ʈЪतႭνڌ 2-3f
ڌ 2-3 ʈЪत
V i Ҝ Hi Low
ණ࢛ 路 ක路
කᗫत (ON) (OFF)
LED 亮 ฮ
I C I C(sat) 0
V CE V CE (sat)Ø0.2V V CC
ཥ౺狀࿒ ཱིձ ࿚˟
ྡ 2-3 ཥ༩ྡ
೯ΈɚίනΣᏀɨ೯ΈdՉනᏀࠥߒ 1.5~2.5 Vd௰ɽτ
Όཥݴމ 50mAdԴࣛ͜ЕટࠢݴཥڜfԷνྡ 2-3 הͪj
(1)߰ LED ʈЪί 1.8Vd20mA ࣛdණཥڜމ
V − V − V 15 − 8 . 1 − 2 . 0
R C Ø CC LED CE ( sat ) Ø Ø650 Ωf
I C 20 m
(2)߰ V BE(sat)Ø0.8VdƺØ100dԴཥ౺ཱིձٙ௰ʃਿཥݴf
I C
I B(min)Ø Ø200 μAdۆ
β
V − V
R B(max)Ø i BE (sat ) Ø21 kΩf
I B (min )