“This is one of the popular instrumentation amplifiers from Analog Devices. The current datasheet is in revision D, and this chip is in a CERDIP case made in the 1980′s so there may be some discrepancies in performance. Unlike some other analog chips we have looked at, this one contains three sets of initials, if the one above can be considered as one.”
Source: http://microblog.routed.net/2007/05/04/ic-friday-analog-devices-amp01/