| ??? 04/23/05 08:42 Read: times |
#92221 - schematic Responding to: ???'s previous message |
hi,
Jan Waclawek said:
But what is the point of having optocouplers, if the supply to the buttons (drived from Vref as you described it) is not decoupled?
I have done two experiments. First one was with non-isolated buttons and the second one with optocouplers. Here is just simple-drawn schematic: The buttons are isolated and have own power. They are connected to a board via long wires. But this poor schematic does very bad results due variable saturation/resistance from optocoupler to optocoupler. Rather, use the optocoupler in a way it really works - as a current-to-current device.
Could you explain it more, please? Especially about nonlinearity of current transfer. Thanks, Oleg |
| Topic | Author | Date |
| ADC as digital input | 01/01/70 00:00 | |
| Saturation | 01/01/70 00:00 | |
| good point | 01/01/70 00:00 | |
| URL | 01/01/70 00:00 | |
| all good, but | 01/01/70 00:00 | |
| optocouplers | 01/01/70 00:00 | |
| Re: ADC as digital input | 01/01/70 00:00 | |
| go analog | 01/01/70 00:00 | |
| schematic | 01/01/70 00:00 | |
| It is possible to do but why..... | 01/01/70 00:00 | |
| opto | 01/01/70 00:00 | |
| Possible but troublesome... | 01/01/70 00:00 | |
| very informative | 01/01/70 00:00 | |
overcomming opto difference | 01/01/70 00:00 |