Hi I made a small production run of boards using nrf9151 where a handful of them have issues with nrf9151 such as not being able to flash. How do I debug the circuit at the board level ? On good boards the dcr of VDD is hiz but on the problematic boards the dcr of VDD is much lower at 12 or 1.2k ohms. On one board the nrf91 is getting hot to the touch so there is a good bet that something shorted internally on that one.
What is the voltage of dec0 supposed to be ? There's no block diagram of the module power but I assume that is an output of a dcdc that needs bulk C bypassing so that's the only way I can think of to tell if the module is powered correctly internally. I'm measuring voltages on dec0 of 2.2V, 1.6V and 0.8V. The good reference board has Vdec0=2.2. This is measured with a dmm which is the best I can do at the moment.
Thanks, Steve
