OPA1602: OPA1602 offset drift with temperature

Hello Zhonghui,

Our Applications Engineer who covers the Precision Amplifiers SoundPlus op amps such as the OPA1602 is on holiday today. He will return next week and may be able to provide you a more qualified answer than I am able to provide at this time.

The SoundPlus operational amplifiers are designed to optimize the parameters which are most important for high performance audio applications. Precision dc parameters which are very important for measurement and industrial applications are secondary and usually non-critical ones in audio applications. Therefore, you will notice in the OPA1602 and other SoundPlus op amp datasheet electrical characteristics table that audio and noise specifications are listed first, and the a mix of dc and ac specifications follow them. Critical dc parameters come first in a precision op amp's electrical characteristics table.

If you look at the various SoundPlus datasheets all list the input offset voltage typical and maximum values, but may not list the input offset voltage drift. That is the case for the OPA1602. Since the OPA1602 uses a closely matched bipolar transistor pair and has specified maximum input voltage offset of ±1 mV (TA = +25°C) the input offset voltage drift is likely on the order of single digit microvolts/°C, and very likely under 10 μV/°C. 

When our Audio op amp products Applications Engineer returns next week he may be able to search and see if the OPA1602 input offset voltage drift (μV/°C) was captured and recorded when the product was originally characterized. Even if we do have that information and can provide it TI makes no assurances about what the OPA1602 input offset voltage drift can be because it is not a parameter listed in the datasheet.

Regards, Thomas

Precision Amplifiers Applications Engineering

Hi Thomas,

thank you for your reply.

I'll wait for your team's further reply.

thank a lot.