What do you want to find?
Output voltage from R1 and R2
R2 for a wanted output voltage
R1, between OUT and ADJ (ohm; 120 to 240 is usual)
R2, from ADJ to ground (ohm)
Wanted output voltage (V)
Input voltage (V)
Load current (A)
Thermal resistance, junction to ambient (C per W)
About 50 for a TO-220 with a small heat sink; 65 without one.
Output voltage
Minimum input voltage (output + 2 V dropout)
Power dissipated in the regulator
Junction temperature rise
Calculator by
Engineer Underground
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