Timeline for What's the performance difference between these two differential amplifiers?
Current License: CC BY-SA 4.0
8 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Sep 26, 2021 at 18:39 | vote | accept | ElectronSurf | ||
| Sep 25, 2021 at 20:08 | comment | added | Davide Andrea | Short answer: because PWM is digital and OP-amps are analog. Rather than modulate the voltage source, consider also the possibility of disabling the MOSFET independently of the analog feedback loop. But, as I said, 100 Hz is slow, so you are probably going to be fine. | |
| Sep 25, 2021 at 18:24 | comment | added | ElectronSurf | Why the circuits are not appropriate for PWM? | |
| Sep 25, 2021 at 18:09 | comment | added | Davide Andrea | Generally, neither circuit is appropriate for PWM. However, at only 100 Hz, it may work. Both circuits will perform about the same as far as the PWM is concerned, but the top one will regulate the current (DC) more accurately, especially if you get a current sense IC, as I recommended in my answer. | |
| Sep 25, 2021 at 17:43 | comment | added | ElectronSurf | If we PWM the reference voltage (V3 in above diagram and V7 in below) at 100Hz with 50% duty cycle, which circuit will perform better? | |
| Sep 25, 2021 at 17:38 | history | edited | Davide Andrea | CC BY-SA 4.0 |
Added a suggested part
|
| Sep 25, 2021 at 17:29 | history | edited | Davide Andrea | CC BY-SA 4.0 |
Simplified
|
| Sep 25, 2021 at 17:23 | history | answered | Davide Andrea | CC BY-SA 4.0 |