Analog Devices Inc./Maxim Integrated LM4040BIX3-5.0+T

Overview

LM4040BIX3-5.0+T from Maxim Integrated is a precision 5.000V two-terminal shunt voltage reference in SC70-3 package, featuring 0.2% initial accuracy, ±100ppm/°C temperature coefficient, and stable operation from -40°C to +85°C. It delivers low 80µVRMS wideband noise (10Hz–10kHz) and maintains regulation across 60μA–15mA shunt current, ideal for high-accuracy analog sensing in portable battery-powered systems.

For engineers reviewing the LM4040BIX3-5.0+T datasheet, LM4040BIX3-5.0+T pinout, LM4040BIX3-5.0+T application, or LM4040BIX3-5.0+T equivalent, key selection criteria include guaranteed reverse breakdown voltage tolerance (±10mV at +25°C), no-output-capacitor stability, ultra-small 1.8mm × 1.8mm footprint, and compatibility with capacitive loads in space-constrained industrial and automotive subsystems.

Technical Context

The LM4040BIX3-5.0+T uses bandgap-based shunt architecture to maintain a precise 5.000V reverse breakdown voltage without requiring external stabilization components. Its laser-trimmed internal resistors ensure tight initial tolerance, while dynamic impedance remains ≤1.1Ω at 1mA, enabling stable reference performance under varying load and temperature conditions.

Designed for direct replacement of Zener diodes in precision biasing circuits, it operates over 60μA–15mA shunt current with no minimum output capacitance requirement and tolerates arbitrary capacitive loading-eliminating stability concerns common in traditional shunt references.

Key Specifications

Pinout & Package

The LM4040BIX3-5.0+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 guidance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLVH431ACDBVR and ADR3450ARJZ-R7, the LM4040BIX3-5.0+T offers optimal balance of fixed 5V accuracy, ultra-small SC70 size, zero external component requirements, and proven stability in shunt configurations-making it the preferred choice for space-constrained, low-power, fixed-voltage reference applications.

Availability

LM4040BIX3-5.0+T is available at Aetrix Electronics and suitable for portable medical sensors, notebook system monitoring, automotive cabin control modules, and industrial process transmitters requiring stable component supply with guaranteed long-term availability.

Supply support for LM4040BIX3-5.0+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 high-performance analog and mixed-signal semiconductor solutions for industrial, communications, computing, and consumer markets.

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

FAQ

What is the guaranteed reverse breakdown voltage tolerance for LM4040BIX3-5.0+T at +25°C?

The LM4040BIX3-5.0+T has a guaranteed reverse breakdown voltage of 5.000V ±10mV at +25°C, corresponding to its 0.2% initial accuracy grade. This tolerance is laser-trimmed and specified in the Electrical Characteristics table for the 5.000V variant under IR = 100μA condition. The device maintains this precision across its full operating temperature range of -40°C to +85°C.

Does LM4040BIX3-5.0+T require an external output capacitor for stability?

No, the LM4040BIX3-5.0+T does not require an external output capacitor for stability. Its internal design ensures unconditional stability with any capacitive load, including large bulk capacitance or long PCB traces. This eliminates BOM cost, reduces layout complexity, and avoids ESR-related oscillation risks common in other shunt references - a key advantage confirmed in the Applications Information section of the datasheet.

What is the minimum operating shunt current for LM4040BIX3-5.0+T, and why is it important?

The LM4040BIX3-5.0+T requires a minimum shunt current of 60μA to maintain regulation and specified accuracy. Below this threshold, the device exits its active reverse-breakdown region, causing output voltage collapse and loss of reference integrity. This value is critical for micropower designs - for example, in battery-backed sensors where sleep-mode current budgets are tight - and must be verified against worst-case conditions including temperature extremes and supply variations.

How does the SC70-3 package of LM4040BIX3-5.0+T compare in size to SOT23-3 alternatives?

The LM4040BIX3-5.0+T uses a 3-pin SC70 package measuring 1.8mm × 1.8mm, which is 50% smaller in board area than standard SOT23-3 packages (typically 2.9mm × 1.6mm). This compact footprint enables placement in ultra-dense layouts such as wearable electronics and miniaturized industrial modules, while maintaining identical pinout functionality and thermal performance characteristics validated per JEDEC JESD51-7 testing.

Can LM4040BIX3-5.0+T be used in automotive applications?

The LM4040BIX3-5.0+T itself is rated for -40°C to +85°C operation and is not AEC-Q100 qualified. However, Maxim offers automotive-grade variants (e.g., LM4040BEX3-5.0+T) with extended -40°C to +125°C operation and formal AEC-Q100 qualification. For non-safety-critical cabin modules operating within commercial temperature limits, LM4040BIX3-5.0+T may be deployed - but mission-critical automotive systems require the /E or /V suffix versions explicitly certified to AEC-Q100 standards.