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Power supply for small tube amp

Posted by: Tomasz Gumny on Mon, 08/03/2009

I'm going to built isolated mains power supply for small tube audio amp.
Input: 230(195..265)VAC
1. heater: 6.3V / 2.2A
2. anode: 270V / 150mA
3. control: 12V / 0.6A
May you help me choose device and design transformer?
PI Expert doesn't support output voltages above 100V. :(
Thanks in advance.


Submitted by John Carpenter on Tue, 08/04/2009

You can use PIXls software to design your power supply. I would suggest starting with a TOP256YN device. If you are going to cross regulate the HV supply, that the load variations on any output will vary the HV output significantly.

Z. Cochrane

Submitted by Tomasz Gumny on Wed, 08/05/2009

Thanks for your answer!
I would give PI Expert last chance. ;)
I've used TOP245YN and defined "anode" output as separate 3 x 90V outputs. Now I get warning:
"Drain voltage close to BVDSS at maximum OV threshold. Verify BVDSS during line surge, decrease VUVON_MAX or reduce VOR."
Suggested VOR for multi-output transformer is 135V. How can I change VUVON_MAX?