Author Topic: interesting AD9850 quirk  (Read 2054 times)

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Offline RerouterTopic starter

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interesting AD9850 quirk
« on: April 21, 2013, 11:04:59 am »
when i first picked up one of the modules off ebay, everything went fine, i was using a 1K resistor and a yellow led to stay within the maximum current rating, as a visual indicator,

after a few days of testing code for other modules, i hooked it back up (this time accidentally with a 270 ohm)  and while testing had a few of the wires pull lose while that code was still running in a constant loop,

now i pulled excessive current from an output, and equally fear i may have pushed 1's into the 2 reserved factory codes, though i do not know which may be the cause,

the actual unique quirk that now has popped up is that both comparator outputs now will only source more than about a mA at a rate of exactly 1Hz, no matter the actual output frequency or phase, which results in the led flashing at 1Hz even with a 5Mhz signal

in the end the output will be buffered by an op amp, but I'm left curious how this behavior might be explained,
for reference to the code I'm using, i reverted to this to while troubleshooting with no change http://nr8o.dhlpilotcentral.com/?p=83





 

Offline codeboy2k

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Re: interesting AD9850 quirk
« Reply #1 on: April 21, 2013, 08:59:06 pm »
I came here expecting to find some cool "quirk" in the chip...

I think she's dead. That's no quirk.   :)



 


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