Analog Devices Inc./Maxim Integrated LM4040AEX3-3.0+T

Overview

LM4040AEX3-3.0+T from Maxim Integrated is a precision 3.000V two-terminal shunt voltage reference in SC70-3 package, featuring 0.1% initial accuracy, ±100ppm/°C temperature coefficient over –40°C to +125°C, 60μA–15mA operating current range, and 28μVRMS wideband noise (10Hz–10kHz). It serves as a stable reference in battery-powered instrumentation and automotive sensor signal conditioning circuits.

For engineers reviewing the LM4040AEX3-3.0+T datasheet, LM4040AEX3-3.0+T pinout, LM4040AEX3-3.0+T application, or LM4040AEX3-3.0+T equivalent, key selection criteria include guaranteed extended-temperature operation, ultra-small SC70 footprint, no external capacitor requirement, and low dynamic impedance for high-accuracy analog front-end design.

Technical Context

The LM4040AEX3-3.0+T uses laser-trimmed bandgap circuitry to deliver precise reverse breakdown voltage regulation without requiring forward biasing. Its internal architecture maintains stable 3.000V output across 60μA–15mA shunt current while tolerating any capacitive load.

It operates over –40°C to +125°C with guaranteed 0.1% initial accuracy and ±100ppm/°C max temperature coefficient at 1mA test current. Reverse dynamic impedance is ≤0.8Ω at 120Hz, enabling minimal voltage drift under varying load conditions.

Key Specifications

Pinout & Package

The LM4040AEX3-3.0+T is housed in a RoHS-compliant 3-pin SC70 surface-mount package (1.8mm × 1.8mm), 50% smaller than SOT23 equivalents. Pin 3 is internally unconnected and 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 TLVH431ACDBVR and ADR3430ARJZ-R7, the LM4040AEX3-3.0+T delivers identical 0.1% accuracy in half the PCB area with no external components-making it optimal for miniaturized, capacitor-free shunt reference designs demanding extended-temperature reliability.

Availability

LM4040AEX3-3.0+T is available at Aetrix Electronics and suitable for portable medical sensors, automotive cabin controllers, industrial process transmitters, and smart energy meters requiring stable component supply across extended temperature ranges.

Supply support for LM4040AEX3-3.0+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 industrial, automotive, and communications applications, with emphasis on high-reliability, low-power solutions.

The LM4040 product line delivers improved precision micropower shunt voltage references optimized for space-constrained, battery-operated, and extended-temperature systems requiring stable, capacitor-free reference performance.

FAQ

What is the guaranteed operating temperature range for LM4040AEX3-3.0+T?

The LM4040AEX3-3.0+T is specified and guaranteed over –40°C to +125°C ambient temperature. This extended range is confirmed in the Ordering Information table and Absolute Maximum Ratings section of the datasheet, making it suitable for under-hood automotive and industrial control environments where thermal robustness is critical. The "E" suffix denotes the extended temperature grade.

Does LM4040AEX3-3.0+T require an external output capacitor for stability?

No, the LM4040AEX3-3.0+T does not require an external output capacitor. Its internal design ensures stability with any capacitive load, including direct connection to ADC reference inputs or op-amp feedback networks. This eliminates BOM cost, layout area, and potential phase-margin issues associated with capacitor selection-confirmed in both the General Description and Applications Information sections.

What is the minimum shunt current needed for LM4040AEX3-3.0+T to maintain regulation?

The LM4040AEX3-3.0+T requires a minimum shunt current of 60μA to maintain regulation across its full temperature range. This value is explicitly listed in the Electrical Characteristics tables for the 3.000V variant and applies to all grades (A/B/C/D) under –40°C to +125°C conditions. Operating below this threshold may result in loss of specified accuracy and increased output impedance.

How does the pinout of LM4040AEX3-3.0+T differ from standard zener diodes?

The LM4040AEX3-3.0+T uses a three-terminal SC70 package with pins labeled "+", "–", and "N.C." Pin 1 (+) is the anode (cathode-side terminal in shunt operation), pin 2 (–) is the cathode (anode-side terminal), and pin 3 is no-connect-unlike two-terminal zeners. This configuration allows explicit grounding of the cathode and simplifies PCB routing while maintaining true two-terminal functional behavior when pin 3 is left open or tied to pin 2.

Is LM4040AEX3-3.0+T AEC-Q100 qualified?

The LM4040AEX3-3.0+T itself is not explicitly AEC-Q100 qualified per the datasheet, but the automotive-grade variant LM4040AEX3-3.0/V+T is listed in the Ordering Information table and referenced in the Benefits and Features section as AEC-Q100 qualified. For automotive applications requiring formal qualification, the /V suffix version must be selected-LM4040AEX3-3.0+T remains suitable for industrial and commercial designs meeting extended-temperature requirements.