Texas Instruments LM4040C25QDBZRG4

Overview

LM4040C25QDBZRG4 from Texas Instruments is a precision 2.5V shunt voltage reference in SOT-23-3 (DBZ) package, rated for –40°C to 125°C operation, with ±12mV (0.5%) initial tolerance at 25°C, 100ppm/°C temperature coefficient, 35μVRMS wideband noise, and stable operation down to 45μA cathode current. It serves as a stable reference in high-accuracy analog signal chains for industrial sensing and automotive control modules.

For engineers reviewing the LM4040C25QDBZRG4 datasheet, LM4040C25QDBZRG4 pinout, LM4040C25QDBZRG4 application, or LM4040C25QDBZRG4 equivalent, key selection criteria include extended-temperature-grade accuracy, low-noise performance at microamp bias, no-output-capacitor stability, and compatibility with space-constrained PCB layouts using the 2.92mm × 1.30mm SOT-23 footprint.

Technical Context

The LM4040C25QDBZRG4 operates as a two-terminal shunt reference, sinking cathode current (IZ) to maintain a precise 2.5V reverse breakdown voltage across its terminals. Its Zener-zap trimmed bandgap core delivers 0.5% initial accuracy and 100ppm/°C drift over –40°C to 125°C, with dynamic impedance under 0.9Ω at 1mA.

It requires no external capacitor for stability and supports all capacitive loads - including direct connection to ADC reference inputs or op-amp feedback networks - while maintaining low 35μVRMS noise across 10Hz–10kHz and long-term stability of 120ppm after 1000 hours.

Key Specifications

Pinout & Package

SOT-23-3 (DBZ) package: 2.92mm × 1.30mm footprint, surface-mount, thermally enhanced plastic body with gull-wing leads.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM4040C25IDBZR, LM4040C25QDBZRG4 adds 125°C operation and tighter thermal hysteresis - critical for automotive and energy infrastructure. Versus REF3025AIDBZR, it trades lower noise for zero-capacitor simplicity and micropower operation, favoring space- and energy-constrained designs.

Availability

LM4040C25QDBZRG4 is available at Aetrix Electronics and suitable for industrial analog input modules, automotive field transmitters, energy infrastructure metering, and precision audio level detection requiring stable component supply across extended temperature ranges.

Supply support for LM4040C25QDBZRG4 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 company specializing in analog and embedded processing technologies, with leadership in precision analog, power management, and signal chain solutions.

The LM4040 family is designed for high-accuracy, low-power shunt voltage reference applications in industrial, automotive, and energy infrastructure systems where stability, small size, and temperature resilience are essential.

FAQ

What is the operating temperature range for LM4040C25QDBZRG4?

The LM4040C25QDBZRG4 is characterized for operation from –40°C to +125°C ambient temperature, making it suitable for under-hood automotive, industrial control, and outdoor energy infrastructure applications where extended thermal performance is required. This rating is confirmed in Section 6.10 of the official TI datasheet (SLOS456Q), which specifies electrical characteristics across the full –40°C to 125°C range for the LM4040C25Q variant.

Does LM4040C25QDBZRG4 require an output capacitor?

No, LM4040C25QDBZRG4 is stable with all capacitive loads and does not require an external output capacitor - a key design advantage over many series references. This feature simplifies PCB layout, reduces BOM count, and improves reliability in space-constrained applications such as portable instrumentation and modular sensor nodes. The datasheet explicitly states this capability in Section 3 (Description) and Section 8.2 (Typical Applications).

What is the initial voltage tolerance of LM4040C25QDBZRG4 at 25°C?

The LM4040C25QDBZRG4 has a maximum initial reverse breakdown voltage tolerance of ±12mV (0.5%) at 25°C, as specified in Table 6.10 of the TI datasheet for the C-grade 2.5V Q-temperature variant. This tolerance applies under test condition I_Z = 100μA and defines the guaranteed voltage deviation before temperature or long-term drift effects are considered.

How much current does LM4040C25QDBZRG4 need to operate correctly?

The LM4040C25QDBZRG4 requires a minimum cathode current (I_Z,min) of 45μA typical and 80μA maximum across temperature to maintain regulation. It operates stably up to 15mA cathode current. This ultra-low minimum current enables use in micropower systems such as battery-backed sensors and energy-harvesting nodes, as verified in Section 6.10 Electrical Characteristics of the TI datasheet.

Is LM4040C25QDBZRG4 pin-compatible with other LM4040 variants in SOT-23-3?

Yes, LM4040C25QDBZRG4 uses the standard 3-pin SOT-23 (DBZ) package with identical pinout (Cathode–Anode–NC) as all other LM4040x25x DBZ variants, including LM4040A25QDBZRG4 and LM4040C25IDBZR. Pin compatibility is confirmed in Figure 5-1 and Table 5-1 of the TI datasheet, enabling drop-in replacement within the same grade and package - though temperature rating and tolerance must be validated per application.