Analog Devices Inc./Maxim Integrated LM4040AEX3-5.0+T

Overview

The LM4040AEX3-5.0+T from Maxim Integrated is a precision 5.000V 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 80µVRMS wideband noise (10Hz–10kHz). It serves as a stable reference in high-accuracy analog signal chains and power monitoring circuits.

For engineers reviewing the LM4040AEX3-5.0+T datasheet, LM4040AEX3-5.0+T pinout, LM4040AEX3-5.0+T application, or LM4040AEX3-5.0+T equivalent, key selection criteria include guaranteed A-grade accuracy at extended temperature, ultra-small SC70 footprint, no external capacitor requirement, and compatibility with capacitive loads in battery-powered and automotive systems.

Technical Context

The LM4040AEX3-5.0+T uses bandgap-based shunt regulation to maintain a precise 5.000V reverse breakdown voltage across its terminals when biased with 60μA–15mA cathode-to-anode current. Its internal laser-trimmed resistor network ensures tight initial tolerance without post-package trimming.

It operates stably with any output capacitance and exhibits low dynamic impedance (≤1.1Ω at 1mA), enabling robust performance under load transients and varying supply conditions. The device is qualified per AEC-Q100 for automotive applications and guarantees operation up to +125°C ambient.

Key Specifications

Pinout & Package

LM4040AEX3-5.0+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 NC and must be left unconnected 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 TLVH431AIDBZR and ADR3450ARJZ-R7, the LM4040AEX3-5.0+T delivers A-grade precision in the smallest footprint with zero external components, making it optimal for space-constrained, high-reliability shunt reference applications where fixed 5V and automotive qualification are mandatory.

Availability

LM4040AEX3-5.0+T is available at Aetrix Electronics and suitable for portable medical sensors, automotive engine control units, industrial process transmitters, and smart energy meters requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for LM4040AEX3-5.0+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 industrial, automotive, and communications markets, emphasizing high reliability and performance in harsh environments.

The LM4040 product line delivers micropower, high-accuracy shunt voltage references optimized for space-constrained, battery-operated, and automotive applications demanding guaranteed performance across –40°C to +125°C.

FAQ

What is the guaranteed operating temperature range for the LM4040AEX3-5.0+T?

The LM4040AEX3-5.0+T is specified for continuous operation from –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, and the device is AEC-Q100 qualified for automotive underhood use. Its performance parameters-including initial accuracy, temperature coefficient, and dynamic impedance-are guaranteed across this full range.

Does the LM4040AEX3-5.0+T require an external output capacitor for stability?

No, the LM4040AEX3-5.0+T does not require an external output capacitor. The datasheet explicitly states "No Output Capacitors Required" and confirms stability "for any output capacitance." This is validated by output impedance vs. frequency plots showing flat response up to 1MHz with and without 1µF load capacitance, eliminating design risk and BOM cost associated with capacitor selection and placement.

What is the minimum shunt current needed for proper regulation of the LM4040AEX3-5.0+T?

The LM4040AEX3-5.0+T requires a minimum shunt current of 60μA to maintain regulation, as specified in the Electrical Characteristics table for the 5.000V version. This value is guaranteed across the full –40°C to +125°C temperature range. Operating below 60μA may cause the output voltage to deviate outside its specified tolerance band, especially at temperature extremes.

How does the LM4040AEX3-5.0+T differ from the LM4040AIM3-5.0+T variant?

The LM4040AEX3-5.0+T uses a 3-pin SC70 package (1.8mm × 1.8mm) and is rated for –40°C to +125°C operation, while the LM4040AIM3-5.0+T uses a larger 3-pin SOT23 package and is rated only to +85°C. Both share identical electrical specifications-0.1% initial accuracy, ±100ppm/°C tempco, and 5.000V nominal output-but the X3 suffix denotes the smaller, higher-temperature SC70 variant optimized for space- and thermal-critical applications.

Is the LM4040AEX3-5.0+T pin-compatible with other LM4040 variants in SC70-3 packages?

Yes, all LM4040 variants in the SC70-3 package-including LM4040AEX3-5.0+T, LM4040BEX3-5.0+T, and LM4040CEX3-5.0+T-share identical pinout: pin 1 = cathode (+), pin 2 = anode (–), pin 3 = NC. The SC70-3 mechanical outline (21-0075) and land pattern (90-0208) are consistent across grades and output voltages, enabling PCB reuse across accuracy and voltage options within the same package family.