Analog Devices Inc. AD587KR

Overview

AD587KR from Analog Devices is a precision 10 V monolithic voltage reference IC using a buried Zener diode architecture, laser-trimmed for ±5 mV initial accuracy and 10 ppm/°C max temperature coefficient over 0°C to 70°C. It delivers 4 μV p-p (0.1–10 Hz) output noise, supports 0–10 mA sourcing/sinking load regulation, and features dedicated TRIM and NOISE REDUCTION pins for system-level calibration and filtering. It serves as a high-stability external reference for 12-bit to 16-bit DACs and ADCs in test equipment and data acquisition systems.

For engineers reviewing the AD587KR datasheet, AD587KR pinout, AD587KR application, or AD587KR equivalent, key selection criteria include its SOIC_N (R-8) package compatibility, fine-trim capability for system calibration, low-drift performance across industrial temperature range, and noise-reduction capacitor interface for sub-μV noise-critical signal chains.

Technical Context

The AD587KR implements a proprietary ion-implanted buried Zener diode combined with laser-trimmed thin-film resistors to achieve superior long-term stability (±15 ppm/1000 hr) and low thermal hysteresis. Its internal buffer amplifier provides fast turn-on settling (60 μs to 0.01%) and robust dynamic load regulation under transient 0–10 mA loads.

It operates from +13.5 V to +36 V input, draws ≤4 mA quiescent current, and integrates dedicated circuitry for optional output trimming (±3% gain adjustment) and external RC-based noise filtering via Pin 8. The device is not a bandgap reference - its Zener-based topology ensures lower drift and lower 1/f noise than competing solutions.

Key Specifications

Pinout & Package

AD587KR is housed in an 8-lead SOIC_N (R-8) package per JEDEC MS-012-AA, with 1.27 mm lead pitch, 5.00 mm × 4.00 mm body, and 1.75 mm max height. Pins 1, 3, and 7 are unconnected internal test points and must remain floating.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar precision voltage reference applications.

Compared with REF5010AIDR and ADR441BRZ, the AD587KR offers unique combination of industry-standard SOIC-8 pinout, integrated trim and noise-reduction interfaces, and proven Zener-based stability at mid-tier cost - making it the preferred upgrade path for legacy 10 V reference designs.

Availability

AD587KR is available at Aetrix Electronics and suitable for high-accuracy data acquisition, portable calibration equipment, and industrial PLC analog output modules requiring stable component supply with guaranteed long-term availability.

Supply support for AD587KR includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Analog Devices is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, headquartered in Norwood, MA, with design centers worldwide and ISO 9001-certified manufacturing.

The AD587 belongs to Analog Devices' precision voltage reference product line, engineered specifically for applications demanding low drift, low noise, and high initial accuracy in industrial, instrumentation, and test equipment environments.

FAQ

What is the maximum input voltage rating for the AD587KR?

The AD587KR has an absolute maximum +VIN-to-ground rating of 36 V. Operation above this voltage risks permanent damage. For reliable long-term performance, Analog Devices specifies recommended operating conditions of +13.5 V to +36 V, with typical use at +15 V. Exceeding 36 V, even momentarily, may degrade the buried Zener junction or internal protection structures. Always include input overvoltage clamping if supply rails are unstable.

Can the AD587KR generate a negative reference voltage?

Yes, the AD587KR can be configured as a −10.000 V reference by grounding the VOUT pin (Pin 6), connecting +VIN (Pin 2) to a positive supply ≥+3.5 V, and routing the GND pin (Pin 4) through a resistor (RS <1 kΩ) to a negative rail (e.g., −15 V). The −10 V output is then taken from Pin 4. This configuration maintains the same temperature coefficient and long-term stability as the standard +10 V mode, provided net current through the device stays within 2.5–10 mA.

Does the AD587KR require external capacitors for stability?

The AD587KR does not require external capacitors for basic stability - it functions correctly with only a 0.1 μF ceramic bypass capacitor from +VIN to GND. However, a 1 μF capacitor on the NOISE REDUCTION pin (Pin 8) is required to achieve the specified 160 μV p-p broadband noise performance. Omitting this capacitor increases noise to ~200 μV p-p. No output capacitor is needed, and adding one may degrade transient response.

How does the TRIM pin (Pin 5) affect the AD587KR's temperature coefficient?

The TRIM pin (Pin 5) adjusts output voltage via an external potentiometer but does not alter the AD587KR's inherent temperature coefficient. Laser trimming ensures the 10 ppm/°C max drift specification holds across the full ±3% trim range. Measured drift remains bounded within the original grade spec - e.g., a unit trimmed to 10.24 V still exhibits ≤10 ppm/°C variation from 0°C to 70°C. This preserves accuracy in thermally varying environments after system calibration.

Is the AD587KR RoHS compliant?

Yes, the AD587KR is RoHS compliant. Per Analog Devices' ordering guide, the "Z" suffix denotes RoHS compliance, and AD587KR is functionally identical to AD587KRZ variants. Both meet EU Directive 2011/65/EU and associated exemptions, with lead-free matte tin finish on leads and halogen-free molding compound. Full compliance documentation is available in Analog Devices' official product change notices.