I am using the P9235A-RB-EVK and the P9222-R-EVK to evaluate a non-standard coil configuration that results in an overall efficiency of 62% after tuning. I have it working pretty well, but when the load increases to where the input power is 4.0W to 4.2W, the transmitter goes into the "Power Limit" state.
There is no information in the datasheet as to what exactly triggers the "Power Limit" state? So what does trigger this state? It doesn't seem to be Over Current or Over Temperature, since those have their dedicated error states. Also, it doesn't seem to be tied to a certain input power value, since I can get past this limit by increasing the input voltage from 5V to 12V.
Also, is there a way for the Application Processor on the receiver side to determine what a 'safe' power draw would be?
I put the original coils back on the SDKs. Same situation with those. The transmitter goes into "Power_Limit" at <=4.2W input power even though this is advertised to be a 5W solution.
I've still not found a datasheet, application note, or SDK documentation that explains what triggers this "Power_Limit" state.