Texas Instruments REF5025SHKJ

Overview

REF5025SHKJ from Texas Instruments is a low-noise, very-low-drift, precision 2.5 V voltage reference IC designed for high-accuracy data acquisition systems. It delivers ±7 mA output current, 40 ppm/°C max temperature drift over –55°C to +210°C, 3 μVPP/V noise, and initial accuracy of ±0.14% at 210°C - enabling use in aerospace-grade ATE and optical control systems requiring stable bias under extreme thermal stress.

For engineers reviewing the REF5025SHKJ datasheet, REF5025SHKJ pinout, REF5025SHKJ application, or REF5025SHKJ equivalent, this page provides verified technical context, validated pin functions, confirmed military-temperature operating limits, real-world load regulation behavior (20–75 ppm/mA), and two rigorously cross-checked alternative parts with documented functional trade-offs.

Technical Context

The REF5025SHKJ implements a proprietary bandgap core with buffered output stage capable of both sourcing and sinking up to ±7 mA while maintaining stability across 1–50 μF capacitive loads. Its TRIM/NR pin provides direct access to the internal bandgap node, enabling external RC filtering (e.g., 1 μF to ground) that reduces integrated 0.1–10 Hz noise by 50%.

Temperature monitoring is supported via the TEMP pin (575 mV @ 25°C, 2.64 mV/°C slope, ~60 kΩ output impedance), intended for analog compensation-not precision thermometry. The device operates from VIN = 3.25 V to 18 V with 0.8–1.5 mA quiescent current and achieves 5.7°C/W junction-to-case thermal resistance in the HKJ ceramic flatpack package.

Key Specifications

Pinout & Package

REF5025SHKJ is housed in an 8-pin CFP (Ceramic Flatpack) HKJ package (6.9 mm × 5.65 mm), rated for –55°C to +210°C operation. The package features ceramic body with metal lid and gold-plated leads for hermetic reliability in harsh environments.

Key Features

Applications

Equivalent & Alternatives

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

Compared with REF5025SHKJ, REF5025MDREP trades hermeticity and extended temperature for lower cost and SOIC compatibility, while ADR4525B offers better noise and drift at room temperature but lacks the military-grade thermal robustness, TEMP monitoring, and supply-chain traceability essential for REF5025SHKJ's target applications.

Availability

REF5025SHKJ is available at Aetrix Electronics and suitable for aerospace data acquisition, downhole instrumentation, and military test equipment requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for REF5025SHKJ 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

Texas Instruments is a global semiconductor leader specializing in analog and embedded processing technologies, with decades of heritage in precision analog design and space-grade component qualification.

The REF50xx family was engineered specifically for high-reliability, high-accuracy voltage reference needs in extreme-environment applications-including aerospace, defense, and energy exploration-where drift, noise, and long-term stability are non-negotiable.

FAQ

What is the maximum operating temperature of the REF5025SHKJ?

The REF5025SHKJ is fully specified and tested from –55°C to +210°C. Its electrical characteristics-including output voltage accuracy, drift, and noise-are guaranteed across this entire range per SBOS502F datasheet revision F. Operation beyond +210°C is not characterized and may compromise reliability or parametric performance. The REF5025SHKJ achieves this rating through specialized die design, ceramic packaging, and rigorous burn-in screening.

Does the REF5025SHKJ require an output capacitor, and what value is recommended?

Yes, the REF5025SHKJ requires an output capacitor between 1 μF and 50 μF for stability, with ESR between 1 Ω and 1.5 Ω. TI recommends tantalum or polymer capacitors within this range; ceramic capacitors with low ESR (<100 mΩ) can cause gain peaking and increased noise. The REF5025SHKJ's internal amplifier loop response is optimized for this capacitance window-deviating outside it risks oscillation or degraded transient response.

Can the REF5025SHKJ be used to generate a negative reference voltage?

Yes-the REF5025SHKJ can serve as the positive reference in a precision inverting amplifier configuration (e.g., with OPA735) to generate a matched negative reference. Figure 27 in the SBOS502F datasheet shows this exact implementation, using resistor matching to preserve temperature coefficient symmetry. The REF5025SHKJ's ability to sink ±7 mA and its low drift make it ideal for such split-supply reference designs where tracking matters.

What is the function of the TEMP pin on the REF5025SHKJ, and how should it be used?

The TEMP pin on the REF5025SHKJ outputs a voltage proportional to die temperature (575 mV at 25°C, +2.64 mV/°C), with ~60 kΩ source impedance. It is intended for coarse temperature monitoring or analog compensation-not precision measurement. To avoid loading error, the REF5025SHKJ's TEMP pin must be buffered with a low-drift op-amp like OPA333 before connection to an ADC or control circuit.

How does the TRIM/NR pin affect noise performance in the REF5025SHKJ?

The TRIM/NR pin on the REF5025SHKJ provides direct access to the internal bandgap node. Connecting a 1 μF capacitor from TRIM/NR to GND forms a low-pass filter (corner ~14 Hz) that attenuates broadband bandgap noise by −21 dB, reducing total 0.1–10 Hz output noise by approximately 50%. This is a verified design technique documented in Section 7.3.4 and Figure 26 of the REF5025SHKJ datasheet.