does anyone know where I can purchase a VQFN20 programming adapter / socket, this is for the ATtiny84 VQFN package, I found one for QFN20 but not VQFN as yet.
3x3mm 0.3mm pitch
Thanks
P.S. or any other suggestions on how to program these little devils!
The only problem is this defeats the object of using a VQFN package as space is tight, anyone else know of a programming adapter or means of programming this MCU
You don't need space for a connector. Just a few bare pads that some spring pins can touch. I usually put them right under the uC on the bottom side of the PCB.
Are you sure the VQFN and QFN can' t use the same adapter with a spacer?
You don't mention where you found the adapter for the QFN20. If it wasn't 3M, then you may want to be aware of the TexTool and FAST adapters, if not for now, for the future: **broken link removed**
Is this the QFN20 you found?
**broken link removed**
Emulation Technology will either have it or can make it for ya as can Aries, Plastronics etc. I have used Emulation Technology in the past and they are good. Not necessarily cheap though. Your cheapest route here by far is to program the device in-circuit as has been suggested.
You don't need space for a connector. Just a few bare pads that some spring pins can touch. I usually put them right under the uC on the bottom side of the PCB.
Not to belabor this, but: Put .020"/.5mm holes where you need test-points or programming access, then populate one of your PCB blanks with these spring-pins: https://www.digikey.com/product-search/en?x=0&y=0&lang=en&site=us&KeyWords=ED90384-nd in those positions. This gives a perfectly-aligned bed-of-nails fixture, and the pins will (just) fit in a 2mm grid.