we are using the adf4158 in a fmcw radar application 76-77Ghz.
Once the registers of the component are initialized, the application works fine and no issues are ever happened, but if a power down (software ) is requested to the adf4158, it is no more able to restart behaving as before after its exit from power down. It seems related to the lock of the pll and after an hardware reset (power supply removed) the radar correctly restart.
The power down is achieved by setting to 1 the pin DB5 and the normal operation by resetting it.
Is there an additional sequence of operations used to exit from the power down state ?
What are the default values of registers used at startup by the adf4158 ?