This project uses a BS170 (N-Channel Enhancement Mode FET) and a IRFU9120N (P-Channel HEXFET Power MOSFET) to control the DC source.
I used this circuit on two different projects where we wanted to control the DC power (+50V @ 4A MAX) to an automated test system via the PC. I wrote the software in AGILENT VEE to control the power up / power down of the test rack. I laid out the PCB?s using ExpressPCB, cost me US$62.00 (for QTY of 3) and had them in 3 days! Overall this circuit works well.
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