K & K Audio Two Terminal Constant Current Source

[rsumperl]

Greetings everyone,
Just wanted to ask if anyone has used the K & K Audio Two Terminal Constant Current Source and what their experience has been like.

Thanks,
Ray

 

[mastodon]

No experience, but those kits are literally nothing more than a depletion mode mosfet, one or two resistors and a trimpot. I don't really see the added value of purchasing this as a kit instead of buying the components and wiring them in a point-to-point fashion.

 

[Raj1]

No experience, but those kits are literally nothing more than a depletion mode mosfet, one or two resistors and a trimpot. I don't really see the added value of purchasing this as a kit instead of buying the components and wiring them in a point-to-point fashion.

I suppose anyone that's asking the OP question probably needs a schematic to build something of similar ilk...

 

[mastodon]

An externally hosted image should be here but it was not working when we last tested it.

Fair enough 😉

 

[Bas Horneman]

K & K Audio Two Terminal Constant Current Source

Which one?

But never mind about the non-cascaded version. Get a cascaded version. (If you plan on using it as a plate load OR in the tail of a LTP) The non-cascaded version would do fine for instance in the output section of say a Baby Huey PP EL84.

And as mastodon says you could build those yourself.

The IXYS IXTP01N100D is reputed to sound better than the Supertex DN2540N5 and that is why K and K now use them. (Actually they use both in the cascaded but one is strategically placed where it has more effect)

Unfortunately us Europeans cannot buy IXYS IXTP01N100D.

 

[zigzagflux]

Only thing I don't care for with the design is they thermally bond the two FETs together on the heat sink. By keeping the lower FET isolated and in free air (it doesn't dissipate much anyway) you reduce long term thermal drift. The upper FETs current is dictated by the lower.

 

[Doz]

Unfortunately us Europeans cannot buy IXYS IXTP01N100D.

Ironically , I used to buy IXYS IGBT's from the Netherlands 😀

Digikey will ship you one...

 

[mastodon]

So will Mouser.

edit: Oops, they won't.

 

[SY]

Two DN2540, three resistors, you have a current source as close to perfect as one could even need in audio. $3 plus a square inch of perf board. Heat sink on the upper FET. You're done. 😀

 

[tinitus]

yeah, we 'noobs' really should learn to do this

but you know, even simple diodes can cause headaches to some us

I wouldn't mind more input on this subject

 

[Magz]

You can even just wire it up lead-to-lead with a couple little Allen-Bradley 1k stopper resistors and a set resistor, and screw it to the unit through the heat sink. Nice and compact.