Texas Instruments REF35409QDBVR

Overview

REF35409QDBVR from Texas Instruments is a nanopower, high-precision series voltage reference delivering 4.096V output with ±0.05% initial accuracy, 12ppm/°C max temperature coefficient (−40°C to +105°C), and 650nA typical quiescent current in a 6-pin SOT-23 package. It serves as a stable excitation source for precision 12–16-bit data converters and low-power sensor signal chains in industrial and medical instrumentation.

For engineers reviewing the REF35409QDBVR datasheet, REF35409QDBVR pinout, REF35409QDBVR application, or REF35409QDBVR equivalent, this page delivers verified electrical specifications, thermal performance data, noise characteristics, enable/shutdown behavior, and real-world implementation guidance for ultra-low-power, high-stability analog systems.

Technical Context

The REF35409QDBVR employs a proprietary bandgap core with curvature compensation to achieve low-drift operation across −55°C to +125°C. Its internal architecture integrates an EN pin for active-low shutdown (0.1µA typ) and an NR pin for external capacitor-based noise filtering-enabling <3.3ppm_P-P (0.1Hz–10Hz) output noise when configured per spec.

It operates as a series reference with 120mV dropout at 5mA load and supports bidirectional output current (±10mA sourcing/sinking). Input voltage range is V_REF + V_DO to 6V, with line regulation of 40–120ppm/V and load regulation of 20ppm/mA (source) / 40ppm/mA (sink) over full temperature range.

Key Specifications

Pinout & Package

REF35409QDBVR is housed in a 6-pin SOT-23 (DBV) package measuring 2.90mm × 1.60mm, optimized for space-constrained PCB layouts while maintaining thermal robustness (R_θJA = 164.4°C/W).

Key Features

Applications

Equivalent & Alternatives

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

Compared with REF35409QDBVR, REF3440QDBVR trades nanopower operation for simplified layout (no NR cap), while ADR3440ARJZ-R7 offers ADI's process heritage but lacks EN/NR features and exhibits higher drift-making REF35409QDBVR optimal for battery-powered, high-resolution, thermally demanding applications.

Availability

REF35409QDBVR is available at Aetrix Electronics and suitable for flow transmitter calibration, blood glucose meter production, servo drive control module design, and power quality analyzer development requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for REF35409QDBVR 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 expertise in precision voltage references and low-power signal chain solutions.

The REF35 family was engineered specifically for ultra-low-power, high-accuracy applications including portable medical devices, industrial IoT sensors, and battery-backed instrumentation-where nanoscale current consumption must not compromise ppm-level stability.

FAQ

What is the maximum operating temperature range for REF35409QDBVR?

The REF35409QDBVR is fully specified from −40°C to +105°C and remains functional across −55°C to +125°C. Its 12ppm/°C temperature coefficient is guaranteed only within the −40°C to +105°C range, making it suitable for under-hood automotive and industrial control environments where extended thermal margins are required. The device maintains 4.096V output stability throughout this range without derating.

How does the NR pin on REF35409QDBVR reduce output noise?

The NR (Noise Reduction) pin on REF35409QDBVR connects to an external capacitor that forms a low-pass filter with internal circuitry, suppressing 0.1Hz–10Hz 1/f noise. With a 1µF capacitor, REF35409QDBVR achieves 3.3ppm_P-P low-frequency noise-critical for DC-coupled applications like thermocouple amplifiers or precision weight scales. Leaving NR unconnected yields the same spec, but adding capacitance improves noise by up to 50% depending on value and layout.

Can REF35409QDBVR drive a 10µF output capacitor directly?

Yes, REF35409QDBVR is stable with output capacitors from 0.1µF to 10µF, provided ESR ≤400mΩ. This wide range allows direct connection to bulk decoupling caps used in ADC reference domains without requiring isolation resistors. The device's internal compensation ensures phase margin remains >60° across this capacitance range, preventing oscillation even under fast load transients such as those seen in multiplexed sensor arrays.

What is the dropout voltage specification for REF35409QDBVR at full load?

The dropout voltage for REF35409QDBVR is 120mV at 5mA load and 250mV at 10mA load, measured at TA = 25°C. This defines the minimum input-to-output headroom required for regulation. For reliable operation across temperature, VIN must be ≥4.216V (4.096V + 120mV) at 5mA, and ≥4.346V at 10mA. Below dropout, VREF collapses nonlinearly-so proper supply sequencing is essential in low-voltage systems.

Does REF35409QDBVR support bidirectional output current, and what are the limits?

Yes, REF35409QDBVR supports both sourcing and sinking: +10mA (source) and −5mA (sink) over full temperature range. This enables direct interfacing with op-amp reference inputs, DAC feedback nodes, or current-sense amplifier bias networks without external buffers. Load regulation is 20ppm/mA when sourcing and 40ppm/mA when sinking-ensuring <0.02% gain error at full sink load in precision current-source designs.