Texas Instruments REF5040MDREP

Overview

REF5040MDREP from Texas Instruments is a military-grade, low-noise, very low-drift precision voltage reference delivering 4.096 V output with ±0.05% initial accuracy, 3 ppm/°C max temperature drift, and 12 µV_PP (0.1–10 Hz) output noise. It sources/sinks ±10 mA, operates from –55°C to +125°C, and is used as the stable reference for 16-bit ADCs such as ADS8326 in high-reliability data acquisition systems.

For engineers reviewing the REF5040MDREP datasheet, REF5040MDREP pinout, REF5040MDREP application, or REF5040MDREP equivalent, key selection criteria include its extended temperature range, TRIM/NR pin for noise reduction and output adjustment, TEMP pin for on-die temperature monitoring, and SOIC-8 package compatibility with high-precision analog signal chains requiring long-term stability and low thermal hysteresis.

Technical Context

The REF5040MDREP implements a proprietary bandgap core with buffered output amplifier, enabling bidirectional current drive (±10 mA) and robust line/load regulation (≤1 ppm/V and ≤30 ppm/mA). Its internal TRIM/NR pin provides direct access to the bandgap node, allowing external capacitor-based low-pass filtering to reduce 0.1–10 Hz noise by up to 50%.

The TEMP pin delivers a ratiometric 575 mV ±15 mV baseline at 25°C with 2.64 mV/°C slope and ~60 kΩ output impedance-intended for system-level temperature compensation, not direct sensing. The device requires 1–50 µF output capacitance (ESR 1–1.5 Ω) and 1–10 µF input bypassing for stability across its full military temperature range.

Key Specifications

Pinout & Package

REF5040MDREP is housed in an 8-pin SOIC package (4.90 mm × 3.91 mm body), with exposed pad option not specified. Pin functions are validated per TI SBOS471B Rev B.

Key Features

Applications

Equivalent & Alternatives

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

Compared with REF5040MDREP, REF5040IDR offers identical performance at lower cost but without military qualification, while ADR4540BRTZ-REEL7 trades package size and feature set (no TEMP/TRIM) for compactness-making REF5040MDREP the sole choice for ruggedized, feature-rich, high-accuracy reference needs.

Availability

REF5040MDREP is available at Aetrix Electronics and suitable for 16-bit data acquisition systems, ATE equipment, and industrial process control applications requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for REF5040MDREP 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 company specializing in analog and embedded processing technologies, with leadership in precision analog ICs and high-reliability components.

The REF50xx family-including REF5040MDREP-is designed for high-precision data acquisition systems demanding ultra-low drift, low noise, and extended temperature operation in aerospace, defense, and industrial environments.

FAQ

What is the operating temperature range of the REF5040MDREP?

The REF5040MDREP is rated for continuous operation from –55°C to +125°C and is qualified per MIL-PRF-38535 Class V. This extended range ensures reliability in harsh environments such as avionics bays, downhole oil/gas tools, and military vehicle electronics where ambient temperatures exceed commercial limits. The REF5040MDREP maintains its 3 ppm/°C max drift specification across this full range.

How does the TRIM/NR pin on the REF5040MDREP function?

The TRIM/NR pin (Pin 5) on the REF5040MDREP provides dual functionality: it allows ±15 mV output adjustment via external resistors or reduces 0.1–10 Hz output noise by 50% when a 1 µF capacitor is connected to GND. This pin accesses the internal bandgap node directly, so capacitor selection affects both noise performance and turn-on settling time. The REF5040MDREP datasheet specifies exact resistor values for trimming and capacitor ESR limits for stability.

Can the REF5040MDREP drive an ADS8326 ADC reference input directly?

Yes, the REF5040MDREP can directly drive the REFIN input of the ADS8326 SAR ADC. Its ±10 mA output capability exceeds the ADS8326's 1.5 mA peak reference current demand, and its 4.096 V output matches the ADC's ideal full-scale range. When paired with a 1 µF NR capacitor and proper 1–50 µF output decoupling (ESR 1–1.5 Ω), the REF5040MDREP maintains the low-noise performance needed for 16-bit accuracy in the ADS8326 system.

What is the purpose of the TEMP pin on the REF5040MDREP?

The TEMP pin (Pin 3) on the REF5040MDREP outputs a temperature-proportional voltage (575 mV at 25°C, +2.64 mV/°C) with ~60 kΩ source impedance. It is intended for system-level thermal compensation-not direct temperature measurement-and must be buffered (e.g., with OPA333) before connection to ADCs or control logic. The REF5040MDREP's TEMP pin enables real-time correction of gain/offset drift in downstream amplifiers or sensors without adding discrete temperature sensors.

Does the REF5040MDREP require an input bypass capacitor?

Yes, the REF5040MDREP requires a 1–10 µF ceramic bypass capacitor between VIN (Pin 2) and GND (Pin 4), placed as close as possible to the pins. This capacitor suppresses supply noise and ensures >80 dB PSRR above 10 kHz, which is essential for maintaining reference accuracy in noisy mixed-signal environments. The REF5040MDREP datasheet specifies minimum capacitance and maximum ESR to prevent instability or degraded transient response.