Texas Instruments REF3440SQDBVRQ1

Overview

REF3440SQDBVRQ1 from Texas Instruments is a precision AEC-Q100 Grade 1 automotive voltage reference delivering 4.096 V output with ±0.05% initial accuracy, 6 ppm/°C max temperature coefficient, and ±10 mA output current capability in a 5-pin SOT-23 (DBV) package. It operates from −40°C to +125°C ambient, draws ≤95 μA quiescent current, and features an enable pin for shutdown mode (≤3 μA). It serves as a stable reference for high-resolution ADCs in battery management systems and traction inverters.

For engineers reviewing the REF3440SQDBVRQ1 datasheet, REF3440SQDBVRQ1 pinout, REF3440SQDBVRQ1 application, or REF3440SQDBVRQ1 equivalent, key selection criteria include its 4.096 V output matching common 12-bit DAC/ADC full-scale ranges, low 3.8 µVPP/V 0.1–10 Hz noise, 25 ppm/1000 hrs long-term stability, and AEC-Q100 qualification for under-hood automotive use.

Technical Context

The REF3440SQDBVRQ1 implements a precision CMOS bandgap core with force-sense architecture-separate OUT_F and OUT_S pins are not present in the 5-pin SOT-23 (REF3440S-Q1) variant, confirming it uses a single-output buffer without Kelvin sensing. Its low dropout (50 mV at 0 mA, 500 mV at 10 mA) enables operation with minimal headroom from supply rails.

It integrates an enable-controlled power gate that reduces quiescent current to ≤3 μA in shutdown while placing the output in high-impedance state. The device achieves 6 ppm/°C drift via box-method characterization across −40°C to +125°C and meets AEC-Q100 HBM ±2500 V / CDM ±1500 V ESD requirements.

Key Specifications

Pinout & Package

REF3440SQDBVRQ1 is packaged in a 5-pin SOT-23 (DBV) case measuring 2.90 mm × 1.60 mm, optimized for space-constrained automotive PCBs. It omits force/sense separation found in 6-pin variants, using a single buffered output.

Key Features

Applications

Equivalent & Alternatives

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

Compared with REF3440QDBVRQ1, REF3440SQDBVRQ1 trades Kelvin sensing for smaller footprint and lower cost-ideal for space-limited BMS slave boards. Against MAX6070BAUT41+T, it delivers tighter accuracy, lower drift, and full automotive qualification at higher quiescent current, making it the sole choice for safety-critical vehicle subsystems.

Availability

REF3440SQDBVRQ1 is available at Aetrix Electronics and suitable for battery management systems, traction inverters, and advanced driver assistance systems requiring stable component supply across extended automotive temperature ranges and long production lifecycles.

Supply support for REF3440SQDBVRQ1 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 automotive-grade precision analog ICs and broad manufacturing scale.

The REF34-Q1 product line was designed specifically for high-reliability automotive applications-including body electronics, powertrain, and ADAS-where precision, low drift, and AEC-Q100 compliance are mandatory.

FAQ

What is the maximum input voltage for REF3440SQDBVRQ1?

The absolute maximum input voltage for REF3440SQDBVRQ1 is 13 V, but the recommended operating range is up to 12 V. Exceeding 13 V risks permanent damage. For reliable operation, maintain VIN ≥ VOUT + VDO (50 mV min at no load, 500 mV at 10 mA), ensuring sufficient headroom across temperature and load conditions. REF3440SQDBVRQ1 must never be operated beyond its 13 V absolute maximum rating.

Does REF3440SQDBVRQ1 require an external capacitor on the output?

Yes, REF3440SQDBVRQ1 requires an output capacitor between 0.1 µF and 10 µF for stability, with 10 µF recommended for optimal noise and transient performance. Ceramic X7R or C0G types are preferred. Omitting the capacitor or using values outside this range may cause oscillation or degraded PSRR. The device is not unity-gain stable without proper output capacitance, and REF3440SQDBVRQ1's internal compensation relies on this external component.

How does the enable pin function on REF3440SQDBVRQ1?

The EN pin on REF3440SQDBVRQ1 controls active/shutdown modes: logic high (≥1.6 V) enables normal operation with ≤95 μA quiescent current; logic low (≤0.5 V) places REF3440SQDBVRQ1 in shutdown, reducing current to ≤3 μA and forcing the OUT pin into high-impedance state. EN must not exceed VIN, and no pull-up is required-the internal bias ensures defined state at power-up.

Is REF3440SQDBVRQ1 compatible with lead-free reflow processes?

Yes, REF3440SQDBVRQ1 is qualified for standard lead-free reflow profiles (peak ≤260°C), but solder heat shift must be considered: typical output voltage shift is <±0.01%, though distributions show up to ±0.02% possible. For highest accuracy systems, TI recommends post-reflow calibration or burn-in. REF3440SQDBVRQ1's DBV package exhibits well-characterized thermal stress behavior documented in SBAS901C Figure 8-21.

What is the short-circuit protection behavior of REF3440SQDBVRQ1?

REF3440SQDBVRQ1 includes internal short-circuit current limiting, clamping output current to 18–22 mA when VOUT is forced to 0 V at 25°C. This protects the device during fault conditions but does not guarantee safe indefinite short-circuit operation-power dissipation must remain within thermal limits. Under sustained short, junction temperature rise depends on RθJA (122.6°C/W) and ambient; REF3440SQDBVRQ1 must be derated per Section 9.4 to avoid exceeding 150°C max TJ.