AD588*

The AD588 represents a major advance in the state-of-the-artn monolithic voltage references. Low initialerror and low tem-perature drift give the AD588 absolute accuracy performancepreviously not available in monolithic form. The AD588 uses aproprietary ion-implanted buried Zener diode, and laser-wafer-drift trimming of high stability thin-film resistors to provideoutstanding performance at low cost.

The AD588 includes the basic reference cell and three additionalamplifiers that provide pin programmable output ranges. Theamplifiers are laser-trimmed for low offset and low drift to main-ain the accuracy of the reference. The amplifiers are configuredo allow Kelvin connections to the load and/or boosters for driv-ng long lines or high current loads, delivering the full accuracyof the AD588 where it is required in theapplication circuit.

The low initial error allows the AD588 to be used as a systemreference in precision measurement applications requiring 12-bitabsolute accuracy. In such systems, the AD588 can provide aknown voltage for system calibration in software, and the lowdrift allows compensation for the drift of other components ina system. Manual system calibration and the cost of periodicrecalibration can therefore be eliminated. Furthermore, themechanical instability of a trimming potentiometer and thepotential for improper calibration can beeliminated by usingthe AD588 in conjunction with autocalibration software.

The AD588 is available in four versions. The AD588JQ andAD588KQ and grades are packaged in a 16-lead CERDIPandare specified for 0 to 70 operation. AD588AQ and BQgrades are packaged in a 16-lead CERDIP and are specified forthe 25 to +85 industrial temperature range.4