Texas Instruments LM4040C25MDBZTEP

Overview

LM4040C25MDBZTEP from Texas Instruments is a precision 2.5 V shunt voltage reference in SOT-23-3 (DBZ) package, featuring ±0.65% initial accuracy, 100 ppm/°C temperature coefficient, 35 μVRMS typical noise, and operation from –55°C to 125°C. It delivers stable reference voltage for high-accuracy analog signal chains in aerospace-grade power-supply monitors and data-acquisition systems.

For engineers reviewing the LM4040C25MDBZTEP datasheet, LM4040C25MDBZTEP pinout, LM4040C25MDBZTEP application, or LM4040C25MDBZTEP equivalent, key selection criteria include guaranteed military-temperature performance, no-output-capacitor stability, low dynamic impedance (0.3 Ω typ at 1 mA), and compatibility with capacitive loads up to 100 µF without oscillation.

Technical Context

The LM4040C25MDBZTEP implements a Zener-based shunt reference architecture trimmed via Zener-zap during wafer sort, achieving 0.65% initial tolerance. Its two-terminal topology requires only an external series resistor for biasing and operates across cathode current from 45 µA to 15 mA.

It exhibits low thermal hysteresis (0.08%), tight long-term stability (120 ppm over 1000 h), and maintains stable regulation without output capacitance-enabling use in space-constrained, battery-powered systems where board area and BOM count are critical.

Key Specifications

Pinout & Package

SOT-23-3 (DBZ) package: 3-pin surface-mount, 1.12 mm max height, JEDEC TO-236 compliant, RoHS-compliant NIPDAU finish, MSL Level-1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with REF3025AIDBZR and LM4040C25QDBZRQ1, the LM4040C25MDBZTEP uniquely combines extended military temperature range, zero-output-capacitor stability, and full defense/aerospace traceability-making it the sole option for DO-254-compliant avionics and radiation-hardened subsystems requiring –55°C startup capability.

Availability

LM4040C25MDBZTEP is available at Aetrix Electronics and suitable for aerospace power-supply monitors, defense-grade data-acquisition systems, and medical instrumentation requiring stable component supply across extended temperature and long lifecycle demands.

Supply support for LM4040C25MDBZTEP 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 headquartered in Dallas, Texas, delivering analog and embedded processing solutions for industrial, automotive, and aerospace markets since 1930.

The LM4040-EP product line was engineered specifically for high-reliability applications demanding extended temperature operation, controlled manufacturing baselines, and full traceability-targeting defense electronics, satellite subsystems, and certified medical devices.

FAQ

What is the maximum cathode current rating for LM4040C25MDBZTEP?

The LM4040C25MDBZTEP has a maximum continuous cathode current (IZ) rating of 15 mA, as specified in its Absolute Maximum Ratings table. Exceeding this value risks permanent damage. In practice, design should maintain IZ within 45 µA to 15 mA for proper regulation, with thermal derating applied above 85°C ambient per the device's θJA = 320.8°C/W specification. The LM4040C25MDBZTEP must be operated within this current window to ensure stable 2.5 V output and long-term reliability.

Can LM4040C25MDBZTEP operate without an output capacitor?

Yes, the LM4040C25MDBZTEP is explicitly designed to be stable with no output capacitor-its two-terminal shunt architecture eliminates phase-margin concerns inherent in series regulators. TI's datasheet confirms stability across all capacitive loads (0–100 µF), including ceramic, tantalum, and electrolytic types. This feature simplifies layout, reduces BOM count, and improves reliability in LM4040C25MDBZTEP-based designs where board space or capacitor aging is a concern.

What is the function of Pin 3 on LM4040C25MDBZTEP?

Pin 3 of the LM4040C25MDBZTEP is internally connected to the silicon substrate and serves no active circuit function. Per TI's datasheet, it must either be left electrically floating or tied directly to Pin 2 (Anode). Connecting Pin 3 to any other node-including logic signals or voltage rails-may cause malfunction or damage due to parasitic diode conduction between Pins 2 and 3. This constraint is critical in LM4040C25MDBZTEP layout verification.

Is LM4040C25MDBZTEP suitable for automotive applications?

The LM4040C25MDBZTEP is not AEC-Q100 qualified and is not recommended for mainstream automotive ECUs. While it operates from –55°C to 125°C-exceeding standard automotive grade-it lacks automotive-specific qualification testing (e.g., HTOL, ESD, vibration). For automotive use, TI recommends the LM4040C25QDBZRQ1 variant instead. The LM4040C25MDBZTEP is intended for defense, aerospace, and medical applications where extended temperature and traceability supersede AEC-Q100 compliance.

How does the LM4040C25MDBZTEP achieve its 0.65% initial accuracy?

The LM4040C25MDBZTEP achieves ±0.65% initial accuracy through laser-trimmed Zener-zap reverse breakdown voltage adjustment performed during wafer sort. This process fine-tunes the Zener voltage post-fabrication, compensating for process variations across wafers. Accuracy is verified at 25°C with 100 µA cathode current and remains valid across the full –55°C to 125°C range with defined temperature coefficient. This trimming method is integral to the LM4040C25MDBZTEP's controlled baseline and military-grade consistency.