Analog Devices Inc./Maxim Integrated LM4040DEX3-5.0+T

Overview

LM4040DEX3-5.0+T from Maxim Integrated is a precision 5.000V, two-terminal shunt voltage reference in SC70-3 package, featuring ±1.0% initial accuracy, ±150ppm/°C temperature coefficient, and guaranteed operation from –40°C to +125°C. It delivers stable reverse-breakdown voltage with 60μA–15mA shunt current capability and low 80μVRMS wideband noise (10Hz–10kHz), ideal for high-reliability analog sensing and power-supply feedback in automotive and industrial systems.

For engineers reviewing the LM4040DEX3-5.0+T datasheet, LM4040DEX3-5.0+T pinout, LM4040DEX3-5.0+T application, or LM4040DEX3-5.0+T equivalent, this page provides verified electrical specifications, thermal performance data, SC70-3 terminal mapping, AEC-Q100-relevant qualification status, and real-world design constraints for shunt reference biasing and load-transient stability.

Technical Context

The LM4040DEX3-5.0+T uses bandgap-based shunt regulation to maintain a fixed 5.000V reverse breakdown voltage across its anode and cathode terminals. Its internal architecture eliminates need for external stabilization capacitors while tolerating any capacitive load - a key differentiator from series references.

It operates over 60μA–15mA shunt current range with dynamic impedance ≤1.5Ω at 1mA, enabling stable regulation under varying supply and load conditions. The D-grade variant trades tighter initial tolerance for extended temperature coefficient (±150ppm/°C) and wider operating range (–40°C to +125°C), targeting cost-sensitive automotive and industrial applications where absolute precision is secondary to robustness.

Key Specifications

Pinout & Package

SC70-3 surface-mount package (Outline 21-0075, Land Pattern 90-0208), RoHS-compliant, with 3 terminals: Pin 1 (+) = cathode, Pin 2 (–) = anode, Pin 3 = no-connect (must be left floating or tied to Pin 2).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TL431ACDBVR and MAX6008AEUR+T, LM4040DEX3-5.0+T uniquely combines two-terminal simplicity, SC70-3 miniaturization, and guaranteed high-temperature operation - making it optimal for retrofitting legacy shunt designs and new automotive ECU layouts where board area and thermal resilience are prioritized over sub-0.5% accuracy.

Availability

LM4040DEX3-5.0+T is available at Aetrix Electronics and suitable for automotive engine control units, industrial sensor interfaces, portable medical devices, and smart energy meters requiring stable component supply with full traceability and long-lifecycle support.

Supply support for LM4040DEX3-5.0+T 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

Maxim Integrated (now part of Analog Devices) designs precision analog and mixed-signal ICs for demanding industrial, automotive, and communications applications, with emphasis on reliability, miniaturization, and low-power operation.

The LM4040 product line delivers micropower shunt voltage references optimized for space-constrained, high-temperature systems where two-terminal simplicity and robust thermal performance outweigh the need for adjustable output or ultra-high initial accuracy.

FAQ

What is the maximum shunt current the LM4040DEX3-5.0+T can safely handle?

The LM4040DEX3-5.0+T is rated for continuous shunt current up to 15mA under normal operation, with absolute maximum reverse current limited to 20mA. Exceeding 20mA risks permanent damage. At 15mA and 5.000V, power dissipation reaches 75mW - within the SC70-3 package's 235mW limit at +70°C, but thermal derating must be applied above that ambient temperature to avoid exceeding +150°C junction temperature.

Does the LM4040DEX3-5.0+T require an external capacitor for stability?

No, the LM4040DEX3-5.0+T does not require an external output capacitor and remains stable with any capacitive load - including 0pF to 10µF - due to its inherent shunt architecture and internal compensation. This eliminates capacitor-related BOM cost, layout complexity, and aging-induced drift concerns present in series references.

How does the LM4040DEX3-5.0+T differ from the A-grade or B-grade versions of the same voltage?

The LM4040DEX3-5.0+T is the D-grade variant: it offers ±1.0% initial accuracy and ±150ppm/°C temperature coefficient, versus ±0.1% / ±100ppm/°C for A-grade. This trade-off reduces cost while maintaining full –40°C to +125°C operation - making LM4040DEX3-5.0+T optimal for automotive and industrial applications where thermal robustness matters more than lab-grade precision.

Can the LM4040DEX3-5.0+T be used in AEC-Q100 qualified designs?

The LM4040DEX3-5.0+T itself is not marked with /V suffix and therefore not formally AEC-Q100 qualified per the ordering table. However, its SC70-3 package, –40°C to +125°C rating, and identical process/test flow to /V variants (e.g., LM4040BEX3-5.0/V+T) support qualification readiness. For production automotive use, specify the /V version; for prototyping or non-safety-critical systems, LM4040DEX3-5.0+T provides compatible performance.

What is the purpose of Pin 3 (N.C.) on the LM4040DEX3-5.0+T?

Pin 3 on the LM4040DEX3-5.0+T is a no-connect terminal - internally unconnected and electrically isolated. Per Maxim's datasheet, it must either be left floating or tied directly to Pin 2 (anode). Connecting Pin 3 to any other net introduces parasitic coupling paths that may degrade noise performance or cause instability, especially in high-frequency or high-EMI environments like automotive ECUs.