This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

BQ51025 - destroyed during testing

Other Parts Discussed in Thread: BQ500215, BQ51025

Hello,


we have a trouble with BQ51025. We have our own design of the wireless power. We use BQ500215 as transmitter and BQ51025 as receiver. Component BQ51025 is destroyed during testing wireless power.
When we put receiver coil on the transmiter coil for the first time, it worked correctly. When the distance between transmiter's coil and receiver's coil was slowly increased, receiver BQ51025 stop to work. There are higher peaks at the receiver coils when are both coils slowly removed.

 Only green LED between RECT and /WPG at the BQ51025 pins is blinking after restart the Transmitter.

 Transmiter is powered to 12 VDC. Receiver has two posibilities output power 5V, 1A -> 5W or 10V, 1A -> 10W.
For three times we have destroyed BQ51025. Do you have any advice how fix it?

Your sincerely,

Tom

  • Are you saying once you increase the coil distance between RX and TX, the RX got damaged?

    Can you capture the waveform on VRECT, VOUT and AC1 of the RX.

    Thanks,

    Wenjia

  • Hello Wenjia,

    we connected the TX PCB to voltage and we put RX coil on the TX coil. LED 1 was turn on at RX PCB. There was output voltage 10V. Load was 100 ohm. Everything was ok. We have tried to test RX-1, during increasing coil distance between RX and TX we hear some noise from coils. After this LED1 on the RX PCB started blinking , there is 0V at the output. We restarted TX PCB and it was the same. We were not sure what happen. We have changed BQ51025 at the RX PCB and RX PCB worked correct. But changing distance of coils destroyed BQ51025 again.


    We made the second RX PCB. This second RX PCB worked well, we tested it with 1Kohm output load. We switch off TX PCB voltage and changed RX PCB load to 100ohm and connected TX PCB to voltage. Second RX PCB was broken, LED 1 was blinking. We changed BQ51025 load was 1 Kohm and it work until we increased distance RX and TX coils. LED1 at RX PCB is switched off.


    It looks unbelievable. Before we will made the third RX PCB we need to know where is mistake.
    TX coil is WURTH 760 308 141 10uH, RX coil is IWAS4832FEEB150J50 15uH

    www.vishay.com/.../iwas4832fe50.pdf
    katalog.we-online.de/.../760308141.pdf


    As a attachments are waveform VRECT blue, VOUT green, AC1 yelow and scheme RX PCB. The first thee pictures are RX-1 PCB the second three pictures are RX-2 PCB.

    scheme RX PCB (JP1, JP2 5W / 10W output)