Texas Instruments LM4040C41IDBZTG4

Overview

LM4040C41IDBZTG4 from Texas Instruments is a precision micropower shunt voltage reference with 4.096 V nominal output, ±0.5% initial accuracy (C grade), 100 ppm/°C temperature coefficient, 35 μV_RMS wideband noise, and stable operation from 45 μA to 15 mA cathode current. It serves as a compact, low-drift reference in analog-to-digital converter biasing and sensor signal conditioning circuits.

For engineers reviewing the LM4040C41IDBZTG4 datasheet, LM4040C41IDBZTG4 pinout, LM4040C41IDBZTG4 application, or LM4040C41IDBZTG4 equivalent, key selection criteria include its SOT-23-3 package, industrial temperature range (–40°C to +85°C), no-output-capacitor-required stability, and compatibility with high-precision data-acquisition front-ends requiring tight voltage tolerance over temperature.

Technical Context

The LM4040C41IDBZTG4 operates as a two-terminal shunt reference: cathode accepts input current while anode connects to system ground, establishing a precise 4.096 V reverse breakdown voltage across the device. Its Zener-zap trimmed silicon design achieves ±0.5% initial accuracy at 25°C and maintains 100 ppm/°C max drift over –40°C to +85°C.

It delivers low dynamic impedance (<0.9 Ω at 1 mA), supports all capacitive loads without oscillation, and exhibits 35 μV_RMS noise (10 Hz–10 kHz) - enabling direct use in 12-bit to 14-bit ADC reference paths without external filtering.

Key Specifications

Pinout & Package

LM4040C41IDBZTG4 is packaged in a 3-pin SOT-23 (DBZ) case measuring 2.92 mm × 1.30 mm, optimized for space-constrained PCB layouts in portable and modular industrial electronics.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TL4050C41IDBZR and REF3040AIDBZR, LM4040C41IDBZTG4 offers the lowest minimum operating current and simplest two-terminal interface - ideal for space- and power-constrained shunt-reference applications where moderate tempco is acceptable.

Availability

LM4040C41IDBZTG4 is available at Aetrix Electronics and suitable for data-acquisition systems, energy infrastructure monitoring, and field transmitter designs requiring stable component supply with guaranteed long-term manufacturability.

Supply support for LM4040C41IDBZTG4 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, space-constrained applications demanding stable voltage references without external components - targeting industrial automation, test equipment, and portable instrumentation.

FAQ

What is the maximum cathode current rating for LM4040C41IDBZTG4?

The absolute maximum cathode current for LM4040C41IDBZTG4 is 25 mA, per TI's Absolute Maximum Ratings table. However, the recommended operating range is 45 μA to 15 mA. Exceeding 15 mA may increase self-heating and degrade long-term stability; sustained operation above 25 mA risks permanent damage. LM4040C41IDBZTG4 must be used with appropriate series resistance to limit current under worst-case supply conditions.

Does LM4040C41IDBZTG4 require an output capacitor for stability?

No, LM4040C41IDBZTG4 is inherently stable with all capacitive loads and does not require an output capacitor - a key differentiator from many series references. This simplifies layout, reduces BOM count, and improves reliability in harsh environments. TI explicitly confirms unconditional stability across the full 0–10 μF range, making LM4040C41IDBZTG4 ideal for applications where board space or capacitor derating is a concern.

What is the thermal hysteresis specification for LM4040C41IDBZTG4?

LM4040C41IDBZTG4 has a maximum thermal hysteresis of 0.08%, defined as the voltage difference measured at 25°C after cycling to –40°C versus after cycling to +125°C. This low hysteresis ensures repeatable reference performance in systems subject to repeated thermal cycling, such as outdoor energy meters or automotive cabin sensors. The value is consistent across all LM4040 grades and package variants, including LM4040C41IDBZTG4.

Can LM4040C41IDBZTG4 be used in extended temperature applications up to +125°C?

No - LM4040C41IDBZTG4 is rated for the industrial temperature range of –40°C to +85°C only. For +125°C operation, TI offers the Q-grade variant LM4040C41QDBZR (or LM4040C41QDBZT), which shares the same 4.096 V output and ±0.5% accuracy but is characterized across –40°C to +125°C. Using LM4040C41IDBZTG4 beyond +85°C violates its specified operating conditions and may cause parametric shift or accelerated aging.

How does the pin configuration of LM4040C41IDBZTG4 differ from SC-70 packaged variants?

LM4040C41IDBZTG4 uses the SOT-23-3 (DBZ) package with Pin 1 = Cathode, Pin 2 = Anode, Pin 3 = NC. In contrast, SC-70 (DCK) variants like LM4040C41IDCKR use a 5-pin body where Pins 4 and 5 are NC, and the active terminals occupy Pins 1 (Anode) and 3 (Cathode). The DBZ layout places cathode and anode on adjacent edges - simplifying routing in dense layouts - whereas DCK spreads terminals farther apart. LM4040C41IDBZTG4's pinout is not interchangeable with SC-70 versions without PCB redesign.