The INA330 datahseet specifies the maximum variation across -40 to +85 degrees C of the current conveyor offset, which is the dominant source of instability. I would like to know what the temperature coefficient of this error is. Is it likely the variation is linear across the -40 to +85 range? My applications will only ever expose the INA330 to a narrow range around room temperature in a well controlled lab, but requires the best possible stability.
Thanks, Jochen
Hello Jochen,
Sorry we have been slow to answer; there has been a lot going on.
The INA330 datasheet only assures that the Current Offset Error Change Over Temperature from +25°C to +85°C, or +25°C to –40°C, will be no greater than ±40 nA. It doesn't provide specific limits for the parameter's stability, or temperature coefficient, and it must be assumed to be able to drift in either direction.
The "CURRENT CONVEYOR OFFSET ERROR CHANGE OVER TEMPERATURE PRODUCTION DISTRIBUTION" graph on datasheet page 5 indicates that over a wide temperature range the offset error can be positive, or negative; however, the distribution is weighted to the positive. Likely, in a relatively temperature stable environment any error in the current due to a temperature change will be a very small fraction of the change observed over the +25°C to +85°C, or +25°C to –40°C, temperature ranges.
Regards, Thomas
Precision Amplifiers Applications Engineering
