AD688ARWZ

Overview

The AD688ARWZ is a high precision ±10 V tracking voltage reference manufactured by Analog Devices Inc. in a 16-lead wide body SOIC package. It provides absolute accuracy with an initial output error of ±4 mV and a temperature coefficient of 8 ppm/°C over the −40°C to +85°C range. The device features low noise performance, typically 6 μV p-p from 0.1 Hz to 10 Hz, and includes flexible Kelvin force and sense terminals for each output. Internal amplifiers deliver up to 10 mA output current while maintaining high impedance ground sensing.

Feature Summary

• Precision tracking outputs with integrated Kelvin connections for eliminating wire resistance errors
• Internal laser-trimmed buffer amplifiers providing full drive capability without external components
• Low output noise with dedicated pin for broadband filtering via external capacitor
• Calibration provisions through Gain Adjust and Balance Adjust pins for fine-tuning

Applications

• Precision measurement systems requiring 12-bit absolute accuracy
• Bipolar Wheatstone bridge driver circuits
• High-performance analog-to-digital and digital-to-analog converter references
• System calibration voltage sources replacing trimming potentiometers

Procurement Notes

Verify the specific suffix ARWZ corresponds to the 16-lead Wide Body SOIC package option RW-16. Confirm that the component grade meets the required initial error and drift specifications for the intended operating temperature range. Ensure ESD precautions are observed during handling due to the sensitivity of the internal buried Zener diode structure.

Selection Notes

Select this model when a monolithic solution offering both positive and negative tracking voltages is required. The wide body SOIC package facilitates surface mount assembly while maintaining robust thermal characteristics. Consider the available gain and balance adjustment pins if application requirements demand higher precision than the standard factory trim allows.

Part Context

The AD688 series utilizes a proprietary ion-implanted buried Zener diode combined with laser wafer drift trimming of high stability thin-film resistors. This architecture ensures outstanding long-term stability and low temperature drift compared to standard bandgap references. The device integrates the basic reference cell with three additional amplifiers configured to maintain accuracy under load.

Replacement Considerations

AD688AQ

FAQ

How does the AD688 handle unused buffer amplifiers?

If one amplifier is unused, its output force and sense pins should be connected together, and its input should be tied to ground to maintain circuit stability.

What is the effect of adding a capacitor to the Noise Reduction pin?

Connecting a capacitor to Pin 7 forms a low-pass filter with the internal resistor, reducing broadband noise but increasing the turn-on settling time.