Other Parts Discussed in Thread: LM76, LM77
We are experiencing massive Temp Sensor errors at -40degC using LM92. So far it is happening on two boards out of two and we are at a very urgent stage of our project.
The temp data is polled often and when it goes wrong around -40degC it looks like the following:
-36.01, -36.01, -36.01, -36.01, -12.01, -76.01, -76.01, -76.01, -226.89, -38.12
Does this look like an I2C communications problem? How far can I2C be used over a ribbon cable, ours is 17 inches? should pull up or pull down resistors be used? Are there any things we can do to improve digital error margin?
Are there pin compatible devices which might work better at -40degC? or have better I2C operation? Can we change the I2C data rate? (I am not a digital designer)
Why does the datasheet only give data down to -25degC? Are we exceeding the range?
Thanks,
Chris