L200 Linear PSU with adjustable output Voltage and Current

GiacomoPascon said:

Without heatsink...

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GiacomoPascon said:

Without heatsink...

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ChrisP58 said:

And the heatsinks need to be on all power semiconductors.

Depending on your settings and load conditions, the current control mosfet could easily dissipate more than your voltage control transistors.

Figure 23 of this datasheet shows a better way of doing a variable current limit. Instead of adding a separate current limit function, it uses the opamp to generate a current error signal that's feed back into the regulating engine of the L200. So no additional power devices are needed.

It does use the ancient LM741 opamp. If you change that, make sure that the replacement opamps inputs can operate near the positive rail. (Many can't)

https://www.mouser.com/Semiconducto...-Regulators/Datasheets/_/N-5cg9g?keyword=L200

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GiacomoPascon said:

"Connecting point A to a negative voltage (for example - 3V/10 mA) it is possible to extend the output voltage range down to 0 V and obtain the current limiting down to this level (output short-circuit condition)."

I chose to use the Mosfet because I need short circuit protection and this circuit doesn't provide it. At least, this is what I understood....

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MacIntoshCZ said:

Yes and no.
Your current will not rise to HIGH value becouse is limited to certain value.
Just add resistor for highest accetable reference voltage to adjust peak current...

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MacIntoshCZ said:

weak power supply?

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crutschow said:

So with no heatsink, the MOSFET became a nice, high temperature heating element.
A MOSFET can generally tolerate no more than about 1W of dissipation without a heatsink.

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GiacomoPascon said:

Are you referring to the Mosfet that blew up on the current regulation?

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