Search for high-voltage, low-current transformer

[holka_bobra]

Hi there,

Im working on a project, which include developing power supply for photomultiplier tube. The details are mostly under discussion, but generally this device should have up to 2kV output voltage and minimum voltage ripple. As I investigated before there are two ways:

1) flyback up to 2kV
2) flyback/boost converter and classic voltage multiplier with diodes and capacitors

With the second one I have no questions, the implementation is clear, but some drawbacks (just in case of the whole project) stops me. The first one - with the flyback - looks more beauterful. The only thing - I have misunderstanding with the transformer choosing.

The criterias are
- turns ratio should be sufficient to provide 2kV output
- dimensions and weight should be miniature
- this is not a DIY project, so parts availability on the market are necessary

And with this ideas I have checked bunch of manufacturers (Murata, Bourns etc.) and I didnt find anything that suits me. And thats why Im here.

May be some of you have an experience with such designs? It will be grateful to hear any suggestion!

[james_s]

Typically you would design a custom transformer for this sort of thing, using an off the shelf ferrite core and bobbin.

You might be able to repurpose a transformer designed for driving CCFL tubes but those are often custom to whatever equipment is using them.

[holka_bobra]

I know about these options, and I already consider it... Im just so suprised that its really impossible to find any transformer on the market (not CCFL) for my purpose

[eliocor]

See LT AN118: https://www.analog.com/media/en/technical-documentation/application-notes/AN118fb.pdf (Royer topology for very low noise/ripple)
Coilcraft FL series: https://www.coilcraft.com/ccfl.cfm / https://www.coilcraft.com/fa2786.cfm
more than miniature:
 https://product.tdk.com/info/en/catalog/datasheets/trans_atb3225_en.pdf followed by voltage multiplier (Cockroft-Walton)

[Jwillis]

I know about these options, and I already consider it... Im just so suprised that its really impossible to find any transformer on the market (not CCFL) for my purpose

To have a transformer ready available for every possible application there would be an infinite stock pile of transformers . So transformers are wound according to application. 
 A photomultiplier tube will  have a range of supply voltage  so you could change the parameters of your application around a suitable transformer.

[holka_bobra]

Many thanks for answers, and especially to eliocor, this app note will be extremely useful for me

[schmitt trigger]

Another excellent AN from the late Jim Williams.

His Application Notes are, without exception, 24k gold.