FIDOCAD]
MC 65 35 0 0 280
TY 75 25 4 3 0 0 0 * C
TY 70 30 4 3 0 0 0 * B
TY 75 40 4 3 0 0 0 * E
MC 120 25 0 0 450
TY 125 40 4 3 90 0 0 * 4.5V
LI 120 25 120 25 0
LI 90 25 90 25 0
LI 80 25 95 25 0
LI 105 25 120 25 0
TY 115 50 4 3 0 0 0 * R1
MC 120 25 0 0 010
MC 120 45 0 0 020
MC 95 45 0 0 220
MC 110 45 0 0 080
LI 80 45 95 45 0
LI 80 45 75 45 0
LI 70 40 70 40 0
MC 65 45 0 0 080
LI 65 35 50 35 0
LI 50 35 50 35 0
LI 50 40 50 40 0
MC 50 35 2 0 000
MC 50 45 2 0 000
TY 65 50 4 3 0 0 0 * R2
TY 95 50 4 3 0 0 0 * LED
LI 65 45 50 45 0
TY 15 60 4 3 0 0 0 * LED 1.8V
TY 15 65 4 3 0 0 0 * R1= (4.5-1.8-0.2)/0.015= 167 Ohm
LI 95 25 105 25 0
TY 15 75 4 3 0 0 0 * Beta forzato: 200/10=20
TY 15 80 4 3 0 0 0 * Ib= Ic\Hfe= 0.015/20= 0.75 mA
TY 15 85 4 3 0 0 0 * R2= (4.5-0.7)/0.00075= 50 kohm
TY 15 70 4 3 0 0 0 * Transostor: 2N3904