AD9850 / AD9851 DDS Module

Way back in November 2000 I published a design for a synthesizer module based around the (now rather long-in-the-tooth) AD9850 DDS chip. The PCBs or complete modules were, in those days, marketed by a small company HF Instruments, a then fresh start up run by a friend of mine , G4KZY.
The module only had limited popularity, and after the first run we discontinued it; HF Instruments merged, changed hands, moved on to bigger things, and I had, by that time moved on to the AD9852 chip (See Projects ) and no longer bothered with that older design

However, that chip and the AD9851 (the faster 180MHz clocked version with its X6 clock PLL) are still around, are relatively low cost, and I've recently had a few enquiries about the module. It has also had a bit of a rebirth for microwavers as part of beacon sources and in locking crystal oscillators. See LckdSrcs.pdf

I have no plans to have any more boards made up - it wasn't even a particularly good layout - but is simple enough to roll your own if you can make PCBs with a resolution good enough for TSSOP ICS with their 0.6mm pad spacing

Therefore, I've made the PCB layout available in ...

This contains the PCB layout as a mirrored 1:1 PDF file for direct printing to acetate or press-n-peel for homebrew PCB manufacture. There is also a layout diagram.
If you want any other version of the layout, just ask and I'll see what is possible

The Construction notes, programming details and updated firmare for the 16F628 PIC are here. AD9850_51_PIC.ZIP

Please note ........
There is a missing track on the PCB, the two +Vdd pins on the left hand side of the IC, while having their decoupling capacitors in place, are not connected to +5V !!!!!!!!!!!
This doesn't stop the device working as the pins are connected internally to the other Vdd pins. But if you make ANY attempt to draw current externally from this point, eg to power a clock oscillator module, its current has to be passed via the internal IC tracks which is likely to destroy them. Been there, done that :-( The wire link needed is shown on the layout diagam.

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