Hello there,
I am building a power supply that will have variable current-limiting and variable output voltage.
I am working on the current-limiting circuit. I read that I need a current sensing resistor, and a current limiting-transistor that limits the voltage to the base of the pass transistor.
When voltage across the current sensing resistor reaches 0.65V, the current limiting transistor starts to conduct voltage away from the pass transistor.
Using ohms law I found that the current sense resistance has to be a function of the output voltage of the PSU, to get the same current limiting across the entire voltage-range.
How can I get this variable current-sense voltage drop?
Thanks! M
I am building a power supply that will have variable current-limiting and variable output voltage.
I am working on the current-limiting circuit. I read that I need a current sensing resistor, and a current limiting-transistor that limits the voltage to the base of the pass transistor.
When voltage across the current sensing resistor reaches 0.65V, the current limiting transistor starts to conduct voltage away from the pass transistor.
Using ohms law I found that the current sense resistance has to be a function of the output voltage of the PSU, to get the same current limiting across the entire voltage-range.
How can I get this variable current-sense voltage drop?
Thanks! M
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