V+ (12V)
|
+------------+
| +------+
Parallel | | |
Port | D1 --- |
| 1N4001 / \ Bobina de Relay
R1 1 ----------- 5 | /---\ |
D(x) ----1k------| Opto- |-----+ | |
| Isolator | +------+
GND -------------| |-+ |
2 ----------- 4| |
CNY 17 or | R2 | /
4N25 | 4.7K B |/ C T1
+--\/\/\/\/---| BC547A or 2N2222A
|\ E
| V
|
Tierra de circuito externo