| ??? 03/15/12 17:02 Modified: 03/15/12 17:02 Read: times Msg Score: +1 +1 Good Answer/Helpful |
#186701 - No best but consider a voltage divider Responding to: ???'s previous message |
There are almost never any "best" design.
You can do a voltage divider solution where one pin drives the divider to 50% of max amplitude. Second pin has zero ohm pull-up resistor so when high signal goes all the way to VCC. Or (since this is 8051 site) consider the reverse. One pin draws resistor to GND. Second pin draws to GND with zero ohm resistor. If you need to load the signal, you may need to buffer it. Just that analog buffers (like an OP-Amp) normally can't match the rise/fall times of digital signals. |
| Topic | Author | Date |
| Making a pulse with 3 different voltage level! | 01/01/70 00:00 | |
| No best but consider a voltage divider | 01/01/70 00:00 | |
| derivative with a DAC? | 01/01/70 00:00 | |
| derivative with configurable ports | 01/01/70 00:00 | |
| Thanks Per And Erik | 01/01/70 00:00 | |
| which derivative | 01/01/70 00:00 | |
| with an OPamp | 01/01/70 00:00 | |
| Thanks Erik | 01/01/70 00:00 | |
| So, you need to make -15V, 0V and +15V? | 01/01/70 00:00 | |
| Hi Dear Kai | 01/01/70 00:00 | |
| 74hc series | 01/01/70 00:00 | |
FPGA | 01/01/70 00:00 | |
| I think you can do it wih one resistor. | 01/01/70 00:00 | |
| Most 8051 Systems????? | 01/01/70 00:00 | |
| Well add a pull-up resistor then | 01/01/70 00:00 | |
| Would prefer to not have to match internal resistors | 01/01/70 00:00 | |
| You cannot match the weak internal active pull-up! | 01/01/70 00:00 | |
| Being pedantic. | 01/01/70 00:00 | |
| Hi David | 01/01/70 00:00 | |
| maybe a couple of mosfets ... | 01/01/70 00:00 | |
| Thanks Richard | 01/01/70 00:00 |