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USB2240 chip heating

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2017/09/04 12:03:20 (permalink)

USB2240 chip heating

I have working on USB2240 - SD to USB bridge, I have incorporated all the required components which is required to run the chip (seen from the USB2240 Evaluation board) on to my PCB, all the parts on the PCB is assembled by PCB manufacturer (No hand soldering is done) I can connect USB2240 controller to my computer and i can see SD card in my computer as mass storage device , i can Read/Write data from the SD card for few seconds, after some time the controller heats up! and shut down it self.
I am supplying 3.3V from a regulator continuously at this time it's not at all heating up, It's heating only when i connect controller to my computer..

I am attaching my schematics along with this thread, please find my mistake.

Note : R46 is not populated on my PCB.
Note 2 : I have also tried connecting CRD_PWR pin to SD card but no use.

Please help
Thank you

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Re: USB2240 chip heating 2017/09/27 10:56:56 (permalink)
Darn it. I had asked if you could post a link to a PDF file to I could read it.
I use Assistive Technology on my computer, so it is difficult to read the jpg file. I never found resistor our 46.Sigh I had not sent message.
CDR_PWR has to be used with a SD Card to put it into a known state.
The SD_CD and SD_WE both need to be connected to ground for normal operation.
I would expect the system to enumerate the card, see nothing is attached, then power back down.
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