AnsweredAssumed Answered

AD9954 Eval board - no sweep output

Question asked by ronaldo.nunez on Jul 30, 2012
Latest reply on Jul 31, 2012 by Kevin.G

Hello Community!

 

I'm trying to set the "linear sweep mode" example on our AD9954 using the eval board and the PC software (parallel port on board adn winXP professional) provided by Analog. But after setup and check the register content, I'm not able to see the frequency sweep in the oscilloscope, neither in the spectrum analyzer. I see a single tone with frequency equal to FTW0 frequency (with "ramp up" button activated) or equal to FTW1 frequency (with "ramp down" button activated). I changed the parameters to see a slowly sweep, but the the device keep sending only a single tone.

 

I checked oscilloscope and spectrum analyzer configurations to certify that I'll be able to see correctly the waveform on them. As I said, I also checked the register content of the AD9954, all the registers are configured as described in the data sheet.

 

All Vcc pins in the board are fed with 1.8V. I'm using  500mV@20MHz as clock source, I try 20x, 10x and bypass multiplier configs, I got the same results described above.

 

Please help me! I need this device working as soon as possible to start the integration with a microcontroller. Have someone experienced the same behavior?

 

Thanks in advance.

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