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Electronics => Repair => Topic started by: bateau020 on February 09, 2022, 06:56:14 am

Title: identify chip marking C721
Post by: bateau020 on February 09, 2022, 06:56:14 am
Been asked by a client to reverse engineer, or at least bring back to life, a device from a provider of theirs that just went bust, and disappeared without any willingness to collaborate. The device is a GPS tracker. The client has a fair amount of these in the field, but since the devices report to the cloud solution from the company that went bust, they now suddenly are paperweights. Hence the request for my involvement. The device is really simple: a Cypres ARM0 SOC with a GSM + GPS module from SIMCOM and some small stuff around it, but there is one chip that puzzles me. See the picture, it is the one in the middle, marked C721, a holographic sticker on it, 10-Lead QFN (2mm × 2mm).
Anyone having an idea? Am afraid it is a cryptographic device.
Title: Re: identify chip marking C721
Post by: fzabkar on February 09, 2022, 11:26:01 am
It looks similar to this one:

https://www.eevblog.com/forum/repair/help-identifying-a-sensor-(i-think)/msg3669799/#msg3669799 (https://www.eevblog.com/forum/repair/help-identifying-a-sensor-(i-think)/msg3669799/#msg3669799)
Title: Re: identify chip marking C721
Post by: bateau020 on February 09, 2022, 11:50:20 am
wow, looks like an I2C pressure sensor. No idea why they put that in there. It being next to the eeprom led me astray. Thanks for the hint.