Analog Devices Inc./Maxim Integrated LM4040AIX3-3.0+T

Overview

LM4040AIX3-3.0+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 max temperature coefficient, and 60μA–15mA operating current range. It delivers stable reverse-breakdown voltage for analog-to-digital converter (ADC) reference, portable battery-powered instrumentation, and industrial sensor signal conditioning.

For engineers reviewing the LM4040AIX3-3.0+T datasheet, LM4040AIX3-3.0+T pinout, LM4040AIX3-3.0+T application, or LM4040AIX3-3.0+T equivalent, key selection criteria include guaranteed -40°C to +85°C operation, no external capacitor requirement, low 45µVRMS wideband noise (10Hz–10kHz), and SC70 footprint compatibility with space-constrained PCB layouts.

Technical Context

The LM4040AIX3-3.0+T uses laser-trimmed bandgap circuitry to maintain precise 3.000V reverse breakdown across its cathode-anode terminals. Its internal architecture eliminates need for output capacitance while tolerating arbitrary capacitive loads - a critical advantage over series references in high-EMI environments.

It operates as a two-terminal shunt device: reverse current (60μA–15mA) flows from cathode to anode to regulate voltage, with dynamic impedance as low as 0.3Ω at 1mA. The SC70-3 package enables thermal resistance of 340.4°C/W (four-layer board), supporting stable performance up to +85°C ambient without derating.

Key Specifications

Pinout & Package

LM4040AIX3-3.0+T is housed in a RoHS-compliant 3-pin SC70 surface-mount package (1.8mm × 1.8mm), 50% smaller than SOT23 alternatives. 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 REF3030AIDBZR, the LM4040AIX3-3.0+T offers superior initial accuracy (0.1% vs. 0.5%/0.2%), eliminates external components, and fits tighter footprints - making it optimal for space- and precision-critical shunt reference roles.

Availability

LM4040AIX3-3.0+T is available at Aetrix Electronics and suitable for portable medical sensors, industrial data loggers, automotive cabin controllers, and test & measurement front ends requiring stable component supply, consistent parametric performance, and long-term production continuity.

Supply support for LM4040AIX3-3.0+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 designs precision analog and mixed-signal ICs for industrial, medical, and automotive applications, emphasizing low power, high accuracy, and small form factor.

The LM4040 product line delivers micropower shunt voltage references optimized for space-constrained, battery-operated, and high-reliability systems where fixed-output stability and minimal external components are essential.

FAQ

What is the guaranteed operating temperature range for LM4040AIX3-3.0+T?

The LM4040AIX3-3.0+T is specified for operation from -40°C to +85°C. This range is confirmed in the Ordering Information table and Absolute Maximum Ratings section of the datasheet. It does not carry the extended -40°C to +125°C rating found on /E suffix variants like LM4040AEX3-3.0+T. Thermal derating begins above +70°C per the SC70 package's 2.90mW/°C specification.

Can LM4040AIX3-3.0+T be used without an external capacitor?

Yes, LM4040AIX3-3.0+T requires no external output capacitor and remains stable with any capacitive load. This is explicitly stated in the General Description and Applications Information sections. Unlike series references, its shunt architecture inherently provides phase margin across all load conditions, eliminating capacitor-related layout constraints and BOM cost.

What is the minimum shunt current needed for regulation in LM4040AIX3-3.0+T?

The LM4040AIX3-3.0+T requires a minimum shunt current of 60μA to maintain regulation, as specified in the Electrical Characteristics table for the A-grade 3.000V variant. This value is measured at TA = TMIN to TMAX and ensures the device stays within its specified voltage tolerance and dynamic impedance performance across temperature.

How does the noise performance of LM4040AIX3-3.0+T compare to other shunt references?

LM4040AIX3-3.0+T delivers 45µVRMS wideband noise (10Hz–10kHz), measured at 100μA operating current. This is lower than standard 3.0V shunt references such as TL431 (typically >100µVRMS) and matches high-precision alternatives like REF3030 (25µVRMS) only when considering bandwidth-limited cases. Its noise profile supports 16-bit ADC applications without additional filtering.

Is pin 3 of LM4040AIX3-3.0+T functional or should it be left unconnected?

Pin 3 of LM4040AIX3-3.0+T is designated N.C. (No Connection) and must be left unconnected or tied to pin 2 (anode). The Pin Configuration diagram and Pin Description section explicitly state that pin 3 is not internally bonded. Connecting it to any other net may compromise regulation accuracy or cause undefined behavior.