ADR431BR

Overview

The ADR431BR is a precision XFET voltage reference from Analog Devices featuring a fixed 2.500 V output with B grade initial accuracy of ±1 mV (±0.04%) and a maximum temperature coefficient of 3 ppm/°C over the −40°C to +125°C range. It operates within a supply voltage range of 4.5 V to 18 V, drawing a typical quiescent current of 800 µA. The device provides high output drive capability, sourcing up to 30 mA and sinking up to −20 mA, while maintaining ultralow noise performance of 3.5 µV p-p in the 0.1 Hz to 10 Hz band without requiring external capacitors.

Feature Summary

• Utilizes patented XFET technology for minimized voltage change versus temperature nonlinearity
• Provides high output current capacity with both sourcing and sinking capabilities
• Features an integrated trim terminal for adjusting output voltage without compromising performance

Applications

• Precision data acquisition systems
• High resolution data converters
• Medical instruments
• Industrial process control systems

Procurement Notes

Verify the specific package variant required, as the base model number does not indicate surface mount type. Confirm that the B grade specifications meet the design requirements for initial accuracy and temperature drift. Ensure the input voltage remains above the minimum headroom requirement relative to the output voltage during operation.

Selection Notes

Select this component when low noise and high accuracy are critical for signal integrity. The B grade offers tighter tolerance than the A grade but requires verification against system budget constraints. Consider the thermal resistance values for heat dissipation if operating near maximum load currents or elevated temperatures.

Part Context

This part belongs to the ADR43x series of ultralow noise XFET voltage references. The family includes variants with different fixed output voltages such as 2.048 V, 3.000 V, 4.096 V, and 5.000 V. All members share similar architectural features including low quiescent current and wide operating temperature ranges.

Replacement Considerations

Direct substitutes include other parts within the ADR43x family such as the ADR430BR or ADR433BR, provided the output voltage matches the application needs. Cross-family replacements require careful evaluation of noise density and temperature coefficient specifications.