Texas Instruments LM4040B50IDBZR

Overview

LM4040B50IDBZR from Texas Instruments is a precision micropower shunt voltage reference with 5.0V nominal output, ±0.2% initial accuracy (B grade), 100ppm/°C temperature coefficient, 35μVRMS wideband noise, and stable operation from 45μA to 15mA cathode current - used in high-accuracy analog input modules and data-acquisition systems requiring low-drift, low-noise references.

For engineers reviewing the LM4040B50IDBZR datasheet, LM4040B50IDBZR pinout, LM4040B50IDBZR application, or LM4040B50IDBZR equivalent, this page delivers verified specifications, package mapping, functional pin roles, real-world use cases, and validated alternative options for industrial and automotive-grade voltage reference selection.

Technical Context

The LM4040B50IDBZR operates as a two-terminal shunt reference, sinking cathode current (IZ) to regulate a stable 5.0V across its terminals. Its Zener-based architecture uses wafer-level fuse and Zener-zap trimming to achieve tight initial tolerance and low thermal drift over –40°C to 85°C.

It requires no external capacitor, maintains low dynamic impedance (<0.9Ω at 1mA), and delivers consistent performance across capacitive loads - enabling direct integration into ADC bias networks, sensor excitation circuits, and precision DAC reference paths without stability concerns.

Key Specifications

Pinout & Package

SOT-23-3 (DBZ) package: compact 2.92mm × 1.30mm footprint with gull-wing leads, optimized for space-constrained PCB layouts and automated assembly.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM4040B50IDBZR, LM4040C50IDBZR trades 0.3% accuracy for lower cost in fixed-shunt topologies, while REF3050AIDBZR offers better TC but demands different circuit architecture and introduces higher noise - making LM4040B50IDBZR optimal for low-complexity, low-noise shunt reference needs.

Availability

LM4040B50IDBZR is available at Aetrix Electronics and suitable for industrial analog input modules, energy infrastructure metering, and automotive cabin sensor hubs requiring stable component supply with guaranteed long-term sourcing.

Supply support for LM4040B50IDBZR 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

Texas Instruments is a global semiconductor leader specializing in analog and embedded processing technologies, with decades of expertise in precision reference design and high-reliability manufacturing.

The LM4040 series was engineered for cost-sensitive, high-accuracy voltage reference applications in industrial, automotive, and portable systems - emphasizing micropower operation, robust thermal performance, and ease of use in shunt configurations.

FAQ

What is the operating temperature range for LM4040B50IDBZR?

The LM4040B50IDBZR is characterized for operation from –40°C to +85°C ambient temperature, matching the industrial temperature grade (denoted by the "I" suffix in the part number). It maintains specified accuracy, noise, and dynamic impedance across this full range without derating.

Does LM4040B50IDBZR require an external output capacitor?

No - the LM4040B50IDBZR is inherently stable with all capacitive loads and does not require an external output capacitor for regulation. This simplifies layout and eliminates capacitor-related drift or ESR-induced instability in precision analog circuits.

How does the pinout of LM4040B50IDBZR differ from LM4040B50IDCKR?

The LM4040B50IDBZR uses the 3-pin SOT-23 (DBZ) package with Cathode–Anode–NC pinout, while LM4040B50IDCKR uses the 5-pin SC-70 (DCK) package where Pins 4 and 5 are NC and Pin 3 is the NC terminal. Both share identical electrical behavior but differ mechanically and in pin count.

What is the minimum cathode current needed for LM4040B50IDBZR to regulate properly?

The LM4040B50IDBZR requires a minimum cathode current of 45μA (typical) to maintain regulation within specification. At currents below this threshold, output voltage may deviate beyond the ±0.2% initial accuracy band - critical for ultra-low-power sensor interface designs.

Can LM4040B50IDBZR be used in place of LM4040A50IDBZR?

Yes, LM4040B50IDBZR can replace LM4040A50IDBZR in most applications, though with reduced initial accuracy (±0.2% vs. ±0.1%). The B-grade part retains identical temperature coefficient, noise, and operating current range - making it suitable where 0.1% tolerance is not mandatory.