I have been experiencing a problem with the AD5700-1 where by one of the carrier frequencies is instead just a HIGH signal. This has happened on separate boards and with both 1200Hz and 2200Hz signals.
The problem will sometimes manifest during use as the frequency becomes noisier until staying HIGH. Power cycling doesn't help and this problem seems to then be permanent.
These boards are hand soldered, which isn't ideal, but are these ICs particularly sensitive to heat or short circuit? These are development boards after all and so working with these ICs has been difficult. I do have the evaluation board CN0267 but for our application the AD5421 isn't suitable and so this has been of limited use.
Are there any recommendations for working with the ICs or any advice you can provide regarding the internal circuitry and what I should watch out for?