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?
Have you made any progress on this? I hope our experts can soon share their ideas on this thread.
All the best!
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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.
Hello, any information/resolution on this topics?
Hello Fabien, for wireless charging, we're not actively promoting outside of our major consumer accounts right now. We don't have the right collateral / support structure to go beyond the major engagements , as every design requires a large degree of support due to the customisation needed . Thanks JE_REN
I did not get any more information on this. I am just planning to characterize the limit on a few samples and than stay within a safe range.
Thanks both of you for your answer. I am also using non standart coil and I am wondering if the device is saying power limit only because the receiver is asking for power while the transmetter is close to the lower frequency limit. But not sure!