flute2k3@hotmail.com
10 W
- Joined
- Nov 26, 2019
- Messages
- 95
badgineer said:Hi
Thanks for the explanation. This was unexpected! I thought I did a decent homework on this
I took the topology from here:
https://ocw.mit.edu/courses/media-arts-and-sciences/mas-836-sensor-technologies-for-interactive-environments-spring-2011/readings/MITMAS_836S11_read02_bias.pdf
(first schematic on page 4) and did not give it much thought.
MIT material used to be the bible of engineering design, can't find any clue of this very weird C2. it could be typo, and it could be good to check with the author about it. none of other opamp has this capacitor in the whole material.
to find a similar size 100/12 Vdc module is not very easy, I don't think it has marketing value from manufacturer point of view. I list the votol EM-50s chips for your design reference, hope it helps.
battery(up to 96V claimed) to 12V - SD4936
http://www.silan.com.cn/en/product/details/151.html
12V to 6V - 78L06
6V to 3.3V - 1117
again I suggest consider using linear regulator for 12V to 5V, can lower the noise instead of adding capacitor on opamp output :wink: