I'm having trouble with my P9242-R based wireless charger that I designed for a client. The chip in question is this:
I used the exact same circuit given in the official datasheet. Followed the layout guidelines.
The issue I'm having is that the board powers on, green LED flashes for a second, then the red LED starts flashing at 4 Hz indicating a fault.
I tried getting the status register value via i2c bus and it seems like it's indicating a "over temperature fault". The problem is I kept getting different values while trying to read the status register via i2c. But the number "6" kept coming up which might indicate the temperature fault according to the datasheet.
Upon further investigation, I also found the Q6 FET to be insanely hot to the touch. I replaced the FET, and yet the new FET continued to be super hot to the touch. I checked for shorts but couldn't find any. The Q6 FET is indicated in the picture below.
Any help would be appreciated! Am I missing something?
Hello avimurali! How's it going? Have you identified the other parts of the circuit that are also heating up? I do hope you could wait for others who are experts on this to give you a definite answer. You might want to interact with the poster from this thread: http://renesasrulz.com/general/f/general---forum/15690/wireless-charger
All the best! Sai RenesasRulz Forum Moderator https://renesasrulz.com/ https://academy.renesas.com/ en-us.knowledgebase.renesas.com/
we are experiencing similar problems with our boards. Once the IC is detecting over-temperature, the Q_DRV1 transistor is swichting on and stays that way indefinitely.
How did you manage to solve this problem? Any advice?
Hi Cwern, Can we see your schematics, layout and BOM?
please see the attached files. We know there is a layout error concerning the measurement of VBRG_IN, which we corrected on the board. The rest is designed according to your reference board.
Hi Cwren, after fixing VBRG_IN did issue persist?
Hi, yes the issue persists.