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14.4V ground reference for ADC
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Zero999:

--- Quote from: Simon on May 19, 2019, 04:37:33 pm ---That won't work. A µC is too slow to react to load changes plus the conversion and communication time of the ADC. Contrary to what youtube channels like Great Scott say using a microcontroller inside such a critically fast control loop does not work.

You could even use the LM358 to measure you current sense resistor now that you have it but specific chips for this job which are essentially a special purpose opamp cost pence/cents.

So what type of voltage regulator is this? what is doing the power control?

--- End quote ---
The problem with the LM358 is its common mode range does not extend to its positive rail.

An op-amp with inputs which do work up to the positive supply can be used with a transistor to amplify and level shift the signal to the 0V rail.

https://www.analog.com/en/analog-dialogue/articles/high-side-current-sensing-wide-dynamic-range.html
wraper:

--- Quote from: Simon on May 19, 2019, 04:37:33 pm ---That won't work. A µC is too slow to react to load changes plus the conversion and communication time of the ADC. Contrary to what youtube channels like Great Scott say using a microcontroller inside such a critically fast control loop does not work.

--- End quote ---
It can work and can show great results. However not just general purpose MCU and it will be very tricky.
Simon:

--- Quote from: Zero999 on May 19, 2019, 06:51:56 pm ---
--- Quote from: Simon on May 19, 2019, 04:37:33 pm ---That won't work. A µC is too slow to react to load changes plus the conversion and communication time of the ADC. Contrary to what youtube channels like Great Scott say using a microcontroller inside such a critically fast control loop does not work.

You could even use the LM358 to measure you current sense resistor now that you have it but specific chips for this job which are essentially a special purpose opamp cost pence/cents.

So what type of voltage regulator is this? what is doing the power control?

--- End quote ---
The problem with the LM358 is its common mode range does not extend to its positive rail.

An op-amp with inputs which do work up to the positive supply can be used with a transistor to amplify and level shift the signal to the 0V rail.

https://www.analog.com/en/analog-dialogue/articles/high-side-current-sensing-wide-dynamic-range.html

--- End quote ---

Yea, it can only go to within 1.5V of the positive rail so a voltage divider would be required each side. You loose a small bit of the 1V range but it can be made to work on the budget. there is already a current sense in the circuit that can be used for what the OP wants.
wraper:

--- Quote from: Arjunan M R on May 19, 2019, 05:15:30 pm ---Here is the circuit i am using to regulate voltage and controlling the current.Please have a look at it and if you spot any error please notify me.
The dumb thing about this is I don't need that precise 12 bit DAC .But i just used it because it is under my budget. :-//
Because Dave used it in his microsupply(REV A).
So i was sure it will work and I don't haveto respin the pcb.

--- End quote ---
It is non functional. For example because all opamps are powered from 5V. EDIT: Nope, not all (point stands) powered from 5V but why in the hell would you note +18 V as VCC?  :-//.
Simon:
hahaha, i had not noticed. I say again to the OP, if your a programmer start on something simpler......
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