Timeline for A question about fully differential amplifier selection
Current License: CC BY-SA 4.0
6 events
| when toggle format | what | by | license | comment | |
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| Feb 14, 2022 at 17:02 | comment | added | user1999 | Hi again, I simulated your circuit in LTspice works very fine in sim. And I wanted to create 0/+10V and 0/-10V outputs from 0/3.3V input. For that I removed Vp and grounded that input; and used 30k resistors instead of 60.6k like here: i.sstatic.net/a6VRZ.png I get what I want in the simulation i.sstatic.net/Due84.png. But wanted to have your opinion. Do you think it is fine to do this? | |
| Feb 11, 2022 at 11:04 | comment | added | Spehro 'speff' Pefhany | I don't think so. The noise is likely primarily from the power supply so one or two will be similarly noisy. If noise is an issue in practice, consider using a DAC chip with a precision reference and interfacing it with I2C or whatever. | |
| Feb 11, 2022 at 11:03 | comment | added | user1999 | I was using two DACs as differential output in my question. So in your circuit if the inputs were also diff ended that would be les sn oisy I guess? | |
| Feb 11, 2022 at 10:58 | comment | added | Spehro 'speff' Pefhany | Vp is just a net name to indicate it's the 3.3V rail. It should reject smallish common-mode noise. You can use a better op-amp than an LM324 but I'm not sure it's necessary. Noise on the 3.3V rail (and DAC output) may be more of a limitation. | |
| Feb 11, 2022 at 10:56 | comment | added | user1999 | Thanks! I simulated this in LTspice as well it outputs as expected. What does Vp indicate? And this is done to reject noise for the galvo mirror correct? | |
| Feb 11, 2022 at 9:59 | history | answered | Spehro 'speff' Pefhany | CC BY-SA 4.0 |
