| Andy Peters 07/01/09 14:57 Read: 220 times Tucson, Az USA |
#166631 - re: relay control Responding to: Lukas Valecky's previous message |
I use NPNs for this -- usually something standard like a 2N2222 or 2N3094. 8051 port pin feeds the transistor base through a resistor, and the emitter is grounded. Then connect the relay coil's positive lead to VCC and the negative lead to the transistor's collector. And don't forget the snubber.
Set the port high to turn the relay on. -a |
| Topic | Author | Date |
| Relay control - 8051... | Lukas Valecky | 07/01/09 07:35 |
| looks good to me but ... | Erik Malund | 07/01/09 07:58 |
Concept seems fine...  | Michael Karas | 07/01/09 09:58 |
| re: relay control | Andy Peters | 07/01/09 14:57 |
| NPN and standard '51? | Jan Waclawek | 07/01/09 15:03 |
| standard 8051 | Andy Peters | 07/01/09 16:32 |
| Ye standard 8051 and the C8051Fxxx ... | Michael Karas | 07/02/09 01:15 |
| two times only... | Steve M. Taylor | 07/02/09 02:40 |
| Relay Drive: Previously, on 8052.com | Andy Neil | 07/02/09 03:02 |
| 'ED2 is "biblical" as far as ports are concerned | Jan Waclawek | 07/02/09 03:04 |
| snubber | Lukas Valecky | 07/02/09 04:03 |
| At both needed! | Kai Klaas | 07/02/09 07:04 |
| AC opener... | Lukas Valecky | 07/02/09 07:22 |
| 12V AC? | Kai Klaas | 07/02/09 07:49 |
| yes... | Lukas Valecky | 07/02/09 08:22 |
| I would drive it by a DC source! | Kai Klaas | 07/02/09 08:32 |
| Just have seen... | Kai Klaas | 07/02/09 16:01 |
a little information | Lukas Valecky | 07/03/09 01:36 |