Analog Devices Inc./Maxim Integrated LM4040CEX3-5.0+T

Overview

LM4040CEX3-5.0+T from Maxim Integrated is a precision 5.000V two-terminal shunt voltage reference in SC70-3 package, featuring 0.5% initial accuracy, ±100ppm/°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-accuracy analog sensing and power-supply feedback in space-constrained industrial and automotive systems.

For engineers reviewing the LM4040CEX3-5.0+T datasheet, LM4040CEX3-5.0+T pinout, LM4040CEX3-5.0+T application, or LM4040CEX3-5.0+T equivalent, key selection criteria include its 5.000V fixed output, SC70-3 footprint compatibility, AEC-Q100-qualified extended temperature range, and no-output-capacitor-required stability under capacitive loads.

Technical Context

The LM4040CEX3-5.0+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 0.5% initial accuracy at +25°C, while thermal design guarantees ±100ppm/°C max drift over -40°C to +125°C.

It operates without external stabilization capacitance and tolerates any capacitive load, enabled by low dynamic impedance (≤1.1Ω at 1mA) and inherent frequency stability. The device exhibits 120ppm long-term stability after 1000 hours and supports forward conduction up to 10mA for bidirectional biasing flexibility.

Key Specifications

Pinout & Package

LM4040CEX3-5.0+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 unconnected (N.C.) and must remain floating or tied to pin 2 per datasheet requirement.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLVH431ACDBVR and MAX6008AEUR+T, LM4040CEX3-5.0+T offers optimal balance of fixed 5.000V accuracy, AEC-Q100 compliance, 15mA shunt capability, and SC70-3 footprint-making it preferred for automotive and industrial designs requiring drop-in reliability without resistor networks or derating for current headroom.

Availability

LM4040CEX3-5.0+T is available at Aetrix Electronics and suitable for portable battery monitoring, automotive engine control units, industrial sensor signal conditioning, and medical patient monitor analog front-ends requiring stable component supply across extended temperature ranges.

Supply support for LM4040CEX3-5.0+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 computing applications, emphasizing high accuracy, low power, and robust reliability.

The LM4040 product line delivers micropower shunt voltage references with fixed outputs from 2.048V to 5.000V, targeting space-constrained systems needing stable, capacitor-free voltage references across harsh thermal environments.

FAQ

What is the guaranteed operating temperature range for LM4040CEX3-5.0+T?

The LM4040CEX3-5.0+T is specified for continuous operation from -40°C to +125°C. This extended range is confirmed in the Ordering Information table and Absolute Maximum Ratings section of the Maxim datasheet, and aligns with its AEC-Q100 qualification for automotive under-hood use. Operation outside this range may cause parametric shift or permanent damage.

Does LM4040CEX3-5.0+T require an external output capacitor for stability?

No, LM4040CEX3-5.0+T does not require an external output capacitor. The datasheet explicitly states "No Output Capacitors Required" and confirms stability "with any capacitive load." This is enabled by its low dynamic impedance and internal compensation, eliminating layout dependencies and reducing BOM count in compact designs.

What is the minimum and maximum shunt current for reliable regulation of LM4040CEX3-5.0+T?

LM4040CEX3-5.0+T requires a minimum shunt current of 60μA and supports up to 15mA for stable 5.000V regulation. The datasheet specifies IRMIN = 54μA (min) / 80μA (max) at TA = +25°C for the C-grade 5.0V variant, with 60μA used as conservative design floor. Exceeding 20mA risks permanent damage per Absolute Maximum Ratings.

How does the pin configuration of LM4040CEX3-5.0+T differ from standard three-terminal references?

LM4040CEX3-5.0+T uses a two-terminal shunt architecture with three physical pins: pin 1 (+) is cathode, pin 2 (–) is anode, and pin 3 is N.C. (no connection). Unlike three-terminal references, it has no separate reference or adjust pin-voltage regulation occurs solely across pins 1 and 2, with pin 3 either left floating or tied to pin 2 as mandated in the Pin Configuration diagram.

Is LM4040CEX3-5.0+T qualified for automotive applications?

Yes, LM4040CEX3-5.0+T is AEC-Q100 qualified, as stated in the Benefits and Features section and reinforced in the Ordering Information table where "/V" suffix variants denote automotive qualification. Its -40°C to +125°C operating range, robust thermal performance, and stress-test validation meet AEC-Q100 Rev G requirements for automotive electronics.