NXQ1TXH5 - Wireless Charger Transmitter

[carlosformigal]

Dear All,

How to reduce the heat dissipation on the NXQ1TXH5 Wireless Charger Transmitter ?

We have followed the Application Note 100% and played with the Smart Power Limiting - SPL and with the Smart Power Reduction - SPR, with no success in reducing the heat dissipation.

The heat dissipation needs to be reduced as the PCB will have to be housed in a head sensitive case.

Support will be highly appreciated.

Regards,

Carlos Formigal

[Luis_PPelayo21]

excuse me sir. Did you find any way to improve heat dissipation with this integrated?

[vicentegomez]

Hi

What do you mean with reduce the heat dissipation?

I believe that you want that the device will be cooler, if this is the case you need to check your design? how did you solder the gnd pin 33? do you follow the SOT617-3 document?

Maybe you need to add some gnd plane on your design to use it as thermal dissipation.

I hope this will help you.

Regards

Vicente Gomez

[carlosformigal]

Hi Pedro,

Thanks a lot for your support.

What I would like to have is a way to reduce the heat dissipation by reducing, for example, the current that goes from the Tx to the Rx. I have followed the NXQ1TXH5 application note and the recommendations for cooling the NXQ1TXH5 chip.

The Wireless Tx will be installed over some temperature sensors that will read the air temperature. When the Wireless Tx is delivering power it heats so much that the temperature sensors are detecting an increase of air temperature, which I want to avoid. I only need to deliver around 400 mA to my Wireless Rx and I was expecting by limiting the current in the Tx to have the NXQ1TXH5 not heating so much.

I know that the heat is the result of miss coupling between the Tx and Rx coils an that the power MOSFETs are inside the NXQ1TXH5 but, due to the mechanical design of our device we really need to avoid the air temperature disturbance caused by the Wireless Tx when charging.

Is there any alternative from NXP to the NXQ1TXH5 where I could have the MOSFET outside the chip and to have a cooler circuit ?

Thanks a lot once more.

With regards,

Carlos