Timeline for Cheap and easy way to power MCU from Li-Ion, and keep it powered during charging
Current License: CC BY-SA 3.0
8 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Jan 7, 2015 at 23:58 | comment | added | Russell McMahon♦ | A MOSFET can be used in place of a diode as a low voltage drop path when on. | | |
| Jan 7, 2015 at 21:46 | comment | added | I. Wolfe | Yeah, you would have to compensate for the diode, or the MCU would have to be ok with receiving 3V instead of 3.3V. So do you plan on putting the top regulator in inhibit mode when on battery power(maybe by using the output of the battery regulator on the inhibit pin)? It might be ok even if you don't, it's not always deadly to regulators to tie outputs together, but I'd still be ready for the possibility. | |
| Jan 7, 2015 at 19:37 | comment | added | FelIOx | I'm scared that Schottky diode will have large forward voltage (0.3+). Also, I'm going to use LE33, and in the datasheet you can see example with 5V regulators (LE50) about how you can make yourself ehm.. "adjustable" psu just by turning on and off the inhibit pins. I think it's safe to apply voltage to output while in inhibit mode. jm.pl/karty/LE33.pdf | |
| Jan 7, 2015 at 18:56 | answer | added | Randy | timeline score: 1 | |
| Jan 7, 2015 at 18:28 | comment | added | I. Wolfe | Conceptually it looks fine, but like tcrosley I would do something to make sure the regulators don't see issues with reverse voltage. | |
| Jan 7, 2015 at 18:27 | comment | added | tcrosley | In addition to what you have, you might be able to get by with just putting Schottky diodes in between each of the outputs of the regulators and the MCU supply pins. | |
| Jan 7, 2015 at 18:00 | review | First posts | |||
| Jan 7, 2015 at 18:00 | |||||
| Jan 7, 2015 at 17:59 | history | asked | FelIOx | CC BY-SA 3.0 |