Simplistic MosFET HV Shunt Regs

diyAudio Chief Moderator
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I see higher Id range is possible in the charts. But not at -2V Vgs area. Q2 probably holds Q1. Do you have a DN2540 to replace for Q2?
 

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Good evening looking for help. I spent couple of frustrating days on the circuit but still not working! The issue is that I have no output at all, the led doesn't light on and on the CCS output I have no current. I started troubleshooting the CCS, this is what I did:
1. connected F+ and F0
2. disconnected zener D1 and D2 across Q1 and Q2
3. 9V input to the CCS with 0,4A wall supply
4. Q1 (DN2540N5) VGS is around 2V
5. Q2 (DN2540N5) VGS is 0V
6. disconnected Q3 (IRF840)
7. tested again voltage across Q1 and Q2 and still same voltages: Q1 VGS around 2V, Q2 VGS=0V

Tested Q1 and Q2 they looks fine

Board made by me from the SSHV2 PDF using easyeda.

Any good idea?