I have build a board using AD9910,I have this problem:
the DC supply for the DDS is connectd from a DC power supply.on board
i have 4 regulators that make the 3.3v and 1.8v for Analog and Digital circuits seperately.
all the system working but the minuit i close like the Weller solder(or other euipment) it cause reset and the signal is lost
i tried firstly to connect a battery instead and it worked good it showed me the problem dont come from the air
it is hardware.
secondly tried all kind of filters(maybee not the right one) to filter the noise out but it didnt help.
i can see the minute i turn on the solder the dds current consumption decrease ,sometimes not all the registers Reset
i have ordered some coilcraft chocks to test. maybe also something with PCB.
The 3.3v plane pass benith the Reset PIN mabe reflect the noise.
do you have suggestions ?