Hi there,
I have been working with a custom development PCB that has an LMK04832 on board. I have been attempting to program the LMK04832 over SPI for a little while now, but have failed to get any response even from the simplest of tests.
I have fully verified that the chip is getting power and all of the SPI control wires are in the right places. I've stripped back my test as much as possible - the below scope outputs are from sending just two packets, 500 ms apart. All signals are 3.3 Vpk-pk and the SCLK is around 166 kHz. The first is the RESET cmd (write val 0x80 to addr 0x0000) and the second is simply trying to read back the value of the LSB of ID_PROD (expecting val 0x63 from addr 0x0005). As you can see, there is no response from the LMK04832.
I have also attempted to switch on an LED attached to Status_LD2, by writing value 0x04 to addr 0x016E (needing logic high, due to how it was wired), and also have monitored the power while shutting it down (POWERDOWN, writing value 0x01 to addr 0x0002), which made no change in the power consumption.
All of these tests lead me to believe that the LMK04832 IC is just not working on this board. Is there anything else it looks like I missed or that you suggest I test before I attempt to replace the IC?
Thanks for any help you can provide,
Anthony