Hi,
I have found this topic:https://support.dialog-semiconductor.com/forums/post/pmic-audio-and-hapt...
They use the Zynq Version of the Chip for their Artix FPGA.
They did mount the inductors for the rails which they didn't use. So what happens to the chip, if they wouldn't mount the inductors? Will the chip start or not? If the rails are enabled, is it ok to let them float and don't mount the inductors?
The same question for the LDOs. What happens if there isn't any load on the enabled rails?
Kind regards
Device:
Sorry for delay. This really depends upon how the device is programmed. From memory , you can configure a channel to start / not-start in the OTP configuration file, and the sequence slot it starts -up in .. and you can control the on/off via HW GPIO also.... there are several permutations.
If a dc-dc channel is not used, the device should be programmed to disable that output (the device loads it configuration from OTP memory on startup) ... so that it does not raise error flags (via the i2c bus etc) to indicate a rail has failed start-up etc. I need to double check this point however.
Runnigng into no load with an LDO is a bit different : we dont specify a minimum load, just maximum... so the device does not need a minimum load. It does need a minimum o/p capacitance if enabled however. Let me check and revert back shortly. Thanks JE_Dialog
Hello Heje,
The recommended solution would be to have the unused LDOs and bucks disabled in the OTP, and then have their input supplies tied to GND.
However, it is not always possible to GND the inputs as some LDOs can have a shared input pin, in this case we would need to disable the LDO in the OTP.
If you were to use an OTP that had additional LDOs and Buck enabled but did not require these regulators, then we would need to make some hardware changes. The LDOs can have their inputs tied to ground, and have their outputs left floating. The bucks can also have their input and feedback tied to GND, you can then leave the LX pin floating. This is not the case for all PMICs.
Kind regards,
ED