ADR439BRZ-REEL7

Overview

The ADR439BRZ-REEL7 is a precision voltage reference from the ADR43x series, utilizing XFET technology to minimize temperature drift curvature. It provides a fixed output of 4.5 V with B Grade accuracy of ±2 mV and a maximum temperature coefficient of 3 ppm/°C over the -40°C to +125°C range. The device operates within an input voltage range of 6.5 V to 18 V, requiring only 2 V of headroom. It features low noise (7.5 µV p-p from 0.1 Hz to 10 Hz), high output drive capability (+30 mA source, -20 mA sink), and includes a trim terminal for voltage adjustment.

Feature Summary

• XFET technology ensures exceptionally low noise and minimized thermal hysteresis without external capacitors.
• High current drive capability allows sourcing up to 30 mA and sinking up to 20 mA.
• Integrated trim terminal enables output voltage adjustment over a 0.5% range.
• Low supply current consumption of 800 µA typical with minimal voltage headroom requirements.

Applications

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

Procurement Notes

Verify the specific package type against the datasheet, as the ADR439B grade is available in both MSOP and SOIC packages. Confirm that the REEL7 suffix corresponds to the required tape and reel quantity for manufacturing integration. Ensure the input voltage supply meets the minimum 6.5 V requirement for proper regulation.

Selection Notes

Select this component when a 4.5 V reference is required with ultra-low noise performance. The B Grade specification is suitable for applications demanding tight initial accuracy and low temperature drift. Consider the trim pin if system-level calibration is necessary to compensate for board-level errors or temperature variations.

Part Context

This part belongs to the ADR43x family of XFET voltage references, which are designed to outperform traditional buried Zener references in noise and power efficiency. The family covers various output voltages, with the ADR439 specifically providing a 4.5 V nominal output. These devices are engineered for high-precision analog signal chains where stability and low drift are critical.

Replacement Considerations

ADR439ARMZ

FAQ

Does the ADR439 require an external bypass capacitor?

No external capacitor is required for basic operation, though a 0.1 µF capacitor at the output can help improve noise suppression.

How can high-frequency noise be reduced when driving large capacitive loads?

An external RC network (e.g., 82 kΩ resistor and 10 nF capacitor) can be connected between the COMP pin and the output to eliminate noise peaking caused by large capacitive loading.