Anode power supply for VFD display ( 5v to 80v stepper PSU )

admin — Tue, 26 Dec 2006 12:57:29 +0000

For my next project (another VFD clock ;), I need a small variable PSU. The main issue with the VFD display, is the power supply. In fact you need 2 differents PSU:

a 5v / 100mA for the filament
a variable 20 to 75v for anodes..

VFD tube like the IV18 need something like 20/30 volts in direct drive and 50/70 volts where they are muxed. As I can not use them in a direct drive, I need a psu that support output from 20 to 75v, by this way, I can dim the display easily and test the whole stuff in a direct.

I already have done several nixie PSU, but this time I want to build something small (doesn’t cost a lot) with really common parts. I decided to look at smaller mosfet, and I found the BS107 .. small TO92 package and 200v ;)

Here the schematic:

With this simple stuff, and a little microcontroler, you can step the output easily. You can use a 220uH inductor with a 5v VCC, or a smaller one 100uH if you have a PSU between 6v to 15v.

/Enjoy the next step

Simple negative power supply (-5V / -12V / -15V)

admin — Sat, 10 Jun 2006 13:40:24 +0000

Sometimes you need a simple negative power supply. The best example is the contrast PSU for common small LCD device. Building -5V from a battery or a wallmart supply isn’t really easy. I decided to build a small device that is able to provide -5V, -12V, -15V. I used the MAX 764/765/766 serie. Simply change the chip to provide the good output.

Here the little schematic:

And here a pic, of the result:

As you can see, this stuff is damm small, use some common parts and can be reuse across different needs. Thanks Maxim for the sample :)

I used a 220uF instead of the 120uF one, and a small inductor but you can use a bigger one, if you need greater current.

Jkx@home » psu

Anode power supply for VFD display ( 5v to 80v stepper PSU )

Simple negative power supply (-5V / -12V / -15V)