Texas Instruments LM4040B30IDBZT

Overview

LM4040B30IDBZT from Texas Instruments is a precision 3.0V shunt voltage reference in SOT-23-3 (DBZ) package, rated for industrial temperature range (–40°C to +85°C), with ±0.2% initial accuracy, 100ppm/°C temperature coefficient, 35μVRMS wideband noise, and stable operation down to 47μA cathode current. It serves as a compact, low-power reference in analog signal chains of data-acquisition systems and field transmitters.

For engineers reviewing the LM4040B30IDBZT datasheet, LM4040B30IDBZT pinout, LM4040B30IDBZT application, or LM4040B30IDBZT equivalent, key selection criteria include its guaranteed 3.0V output tolerance at 100μA test current, dynamic impedance ≤0.9Ω at 1mA, thermal hysteresis of 0.08%, long-term stability of 120ppm over 1000 hours, and compatibility with all capacitive loads without external compensation.

Technical Context

The LM4040B30IDBZT operates as a two-terminal shunt reference, sinking cathode current (IZ) to maintain a precise 3.0V reverse breakdown voltage across its terminals. Its Zener-zap trimmed silicon design ensures tight initial tolerance and low drift, with internal fuse-based calibration enabling grade-specific accuracy and temperature coefficient specifications.

It functions within a cathode current range of 47μA (min) to 15mA, delivering stable regulation despite load capacitance variations and exhibiting low dynamic impedance (≤0.9Ω) and low noise (35μVRMS, 10Hz–10kHz). The device requires no output capacitor and is characterized across –40°C to +85°C ambient conditions.

Key Specifications

Pinout & Package

SOT-23-3 (DBZ) package: 2.92mm × 1.30mm footprint, surface-mount, thermally efficient for space-constrained PCBs in portable and industrial modules.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM4040C30IDBZT, the LM4040B30IDBZT delivers twice the initial accuracy at identical cost and package; versus REF3030AIDBZR, it offers simpler two-terminal integration and capacitive-load immunity, though with slightly higher tempco and no sink/source flexibility.

Availability

LM4040B30IDBZT is available at Aetrix Electronics and suitable for industrial data acquisition, field transmitter calibration, and energy infrastructure monitoring requiring stable component supply with guaranteed long-term availability and consistent parametric performance.

Supply support for LM4040B30IDBZT 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 micropower operation and robust voltage reference stability - targeting industrial sensing, process control, and portable instrumentation markets.

FAQ

What is the guaranteed output voltage tolerance of LM4040B30IDBZT at 25°C?

The LM4040B30IDBZT guarantees ±0.2% initial output voltage tolerance at 25°C and I_Z = 100μA, corresponding to a 3.0V output ranging from 2.994V to 3.006V. This specification is verified per TI's production test flow and applies to every unit shipped, ensuring predictable system-level accuracy without post-manufacture trimming.

Can LM4040B30IDBZT operate with no output capacitor?

Yes, the LM4040B30IDBZT is explicitly designed to be stable with all capacitive loads and requires no output capacitor for regulation. Its internal architecture eliminates phase-margin concerns common in series references, allowing direct connection to ADC VREF pins or op-amp inputs without risk of oscillation - a key advantage in miniaturized layouts.

What is the minimum cathode current needed for regulation in LM4040B30IDBZT?

The LM4040B30IDBZT maintains regulation with a minimum cathode current of 47μA (typical) and 82μA (max) across –40°C to +85°C. At 25°C, regulation is assured down to 47μA, enabling use in ultra-low-power applications such as battery-operated field sensors and energy-harvesting nodes where current budgets are sub-100μA.

How does thermal hysteresis affect LM4040B30IDBZT performance in cyclic environments?

The LM4040B30IDBZT exhibits 0.08% thermal hysteresis - meaning voltage measured at 25°C after cycling to –40°C differs by ≤±2.4mV from voltage measured at 25°C after cycling to +125°C. This ensures repeatable calibration stability in equipment subjected to repeated thermal cycling, such as outdoor-mounted industrial controllers or automotive ECUs.

Is LM4040B30IDBZT compatible with high-EMI environments like motor drives or switch-mode power supplies?

Yes - TI recommends connecting the NC pin (Pin 3) to the anode in high-EMI environments, which reduces noise coupling into the reference node. Combined with its low 35μVRMS noise and inherent shunt topology immunity to supply ripple, the LM4040B30IDBZT maintains stable 3.0V regulation even when placed near transformers or high-frequency switching nodes.