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TMP112: I2C Failure at Low Temp (-40C)

Part Number: TMP112

Hello team,

My customer is having an issue with the TMP112 not responding on I2C at low temperatures. 

"When running the card at cold (-40C) @400Khz, we are having issues with the I2C lines talking to the temp sensor. We have faults that are generated when we are unable to access the temp sensor. We try to read the temp sensor after boot up of the device (~ 2 – 15 mins) after we let it soak in cold, while device powered off (-40C) for 15 mins. Usually a power cycle resolves the issue, but then it can repeat itself  on subsequent cold boots.  This issue has only been observed at cold temperatures.

Running at 400Khz, the issue is more prominent. However, slowing the speed to 100Khz, reduces issue replication significantly. 

However, trying to hook up wires / probes to capture the failure on the scope, issue does not replicate. Below is a scope grab using lecroy probes, when the failure cannot be replicated (500MHz; 10pF; 10MΩ)

The TMP112 has approximately 1.3” trace length (calculated approximately ~24pf capacitance) and using pull up resistors of 2K. We also have signal integrity series resistance of 40 ohms on the SCL and SDA lines."

Any thoughts on what could be causing this issue?

Thanks,

Austin Allen