goldenreference high voltage power supply (GRHV)

[jamesmking]

 

On 8/19/2025 at 11:00 AM, psyduck said:

Hello @jamesmking. How is the current limit calculated from the current sense resistor?

on the golden reference HV you need enough voltage across the 5.1ohm 5W current sense resistor (R11 on the positive rail) to activate the current limit. 

*If* I remember correctly the stock 5.1 Ohm gives about 90mA and 2.6ohm (two 5.1ohms in parallel) gives about 175mA.

V(drop)=IR so you are looking at about 0.09A*5.1Ohm = ~0.46V to activate the current limiter so

V/I = R 0.46V/you required current in A = current senses resistor in ohms. 

This resistor value will probably need some fine tuning and you ideally want to use a 5W part rated for high voltage.

 

Edited 2 hours ago by jamesmking