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how to understand the functionality of circuit

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audio:
dear all,,

I wanted to understand this circuit, which has cc cv functionality. How to read the circuit and understand the functionality.

bob91343:
I would suggest you download the data sheet for the 723 voltage regulator and read the applications section.  It should describe some similar circuits.

Basically the 723 can supply a small amount of current and the power transistors enable much larger currents.  The standard mode for the 723 is CV.  You can get CC by overriding the voltage feedback with a current sensor and some gain.

ledtester:
Besides the datasheet, this is a pretty introduction to the LM723:

https://microcontrollerslab.com/lm723-variable-voltage-regulator/

Then this is a good video going over a simple LM723-based power supply:

LM723 Regulator with Voltages and Maths UEENEEH138A TAFE NSW - Greg Moore
https://youtu.be/tabIyItWlzw

Also check out the write-up that goes along with the video:

https://www.learn.org.au/ueenee-course-pages/ueeneeh138a-fault-complex-power-supplies/psu-week-6/

audio:
Thank You sir..

Sir,
In this Circuit Current Sense Resistor 0.33ohm, when 1A current flows through it then there shall be 0.33V . How this would sense 0.7V which is required to turn on current sense transistor. There is a 1K potentiometer which is going to limit the current in  to the base of current sense transistor?

basinstreetdesign:

--- Quote from: audio on January 16, 2022, 02:03:50 am ---Thank You sir..

Sir,
In this Circuit Current Sense Resistor 0.33ohm, when 1A current flows through it then there shall be 0.33V . How this would sense 0.7V which is required to turn on current sense transistor. There is a 1K potentiometer which is going to limit the current in  to the base of current sense transistor?

--- End quote ---

This circuit does not current limit at 1A.  It current limits at 2A.
It can SUPPLY 1A safely itself but is designed to limit the short-circuit current to more than that.
The datasheet for the LM723 is here: