AD688AQ

Overview

The AD688AQ is a high precision ±10 V tracking voltage reference manufactured by Analog Devices Inc. It utilizes a proprietary ion-implanted buried Zener diode and laser-trimmed thin-film resistors to deliver absolute accuracy without external adjustments. The device features low initial error of 5 mV, low tracking error of 3 mV, and temperature drift of 3 ppm/°C over the −40°C to +85°C range. It includes three internal amplifiers for Kelvin connections and flexible output configurations in a 16-lead CERDIP package.

Feature Summary

• Provides precision ±10 V tracking outputs with integrated Kelvin force and sense connections to eliminate wire resistance errors.
• Delivers high absolute accuracy through laser wafer drift trimming of high stability thin-film resistors and a buried Zener reference cell.
• Includes three internal buffer amplifiers configured for ground sensing and full Kelvin output capability.

Applications

• Precision measurement systems requiring 12-bit absolute accuracy
• System calibration references eliminating periodic recalibration needs
• Bipolar Wheatstone bridge driver circuits

Procurement Notes

Verify the specific ordering suffix 'Q' corresponds to the 16-lead CERDIP package option when sourcing. Confirm that the component meets the required environmental specifications for the −40°C to +85°C operating range. Ensure compatibility with ±13.5 V to ±18 V supply voltages during integration planning.

Selection Notes

Select the AD688AQ when applications demand high precision tracking between positive and negative rails without external components. This model is suitable for designs requiring low initial error and minimal temperature drift. Consider the available fine-trim pins if higher symmetry or exact magnitude adjustment is necessary beyond factory settings.

Part Context

The AD688 series represents a family of high precision monolithic voltage references designed for demanding analog applications. The AD688AQ specifically denotes the commercial grade version housed in a ceramic dual in-line package. It shares architectural similarities with other ADI precision references but distinguishes itself through integrated buffering and tracking capabilities.

Replacement Considerations

Cross-reference with AD688BQ for lower initial error specifications within the same package type. Evaluate AD688ARWZ for surface mount requirements using the wide body SOIC package. Verify pinout and electrical parameter compatibility before substituting.