Texas Instruments LM4040B41IDBZT

Overview

LM4040B41IDBZT from Texas Instruments is a precision micropower shunt voltage reference with 4.096 V nominal output, ±0.2% initial accuracy (B 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 voltage reference in high-resolution ADC biasing and industrial sensor signal conditioning circuits.

For engineers reviewing the LM4040B41IDBZT datasheet, LM4040B41IDBZT pinout, LM4040B41IDBZT application, or LM4040B41IDBZT equivalent, key selection criteria include output tolerance over –40°C to +85°C, dynamic impedance under 0.9 Ω at 1 mA, thermal hysteresis ≤0.08%, long-term stability of 120 ppm, and compatibility with all capacitive loads without external compensation.

Technical Context

The LM4040B41IDBZT operates as a two-terminal shunt reference, sinking cathode current (I_Z) to maintain a precise reverse breakdown voltage (V_Z = 4.096 V) across its terminals. Its Zener-zap trimmed silicon junction delivers tight initial tolerance and low drift via fused wafer-level calibration.

It requires no output capacitor and remains stable with any capacitive load due to inherently low dynamic impedance (≤0.9 Ω) and minimal voltage change vs. cathode current (≤6 mV over 1–15 mA). Thermal hysteresis is specified at 0.08% after cycling between –40°C and +125°C.

Key Specifications

Pinout & Package

LM4040B41IDBZT is packaged in a 3-pin SOT-23 (DBZ) surface-mount package measuring 2.92 mm × 1.30 mm. The device uses a two-terminal shunt topology with an optional third terminal for EMI mitigation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM4040C41IDBZT, the LM4040B41IDBZT provides tighter initial tolerance for uncalibrated systems; compared with REF4340, it offers simpler two-terminal integration and micropower operation but trades off absolute drift performance.

Availability

LM4040B41IDBZT is available at Aetrix Electronics and suitable for industrial sensor signal chains, portable data loggers, and energy metering systems requiring stable component supply with guaranteed long-term availability and traceable sourcing.

Supply support for LM4040B41IDBZT 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 ICs and industrial-grade components.

The LM4040 series was designed specifically for high-accuracy, low-power shunt reference applications in data acquisition, sensor interfaces, and portable instrumentation where size, stability, and simplicity are critical.

FAQ

What is the maximum cathode current rating for LM4040B41IDBZT?

The absolute maximum cathode current for LM4040B41IDBZT is 25 mA, but the recommended operating range is 45 μA to 15 mA. Operating above 15 mA increases self-heating and may degrade long-term stability and tempco performance. The device's 206°C/W junction-to-ambient thermal resistance means sustained 15 mA dissipation at 4.096 V (61.4 mW) raises junction temperature by ~12.7°C above ambient.

Does LM4040B41IDBZT require an output capacitor for stability?

No, LM4040B41IDBZT is explicitly designed to be stable with all capacitive loads and does not require an output capacitor. Its low dynamic impedance (<0.9 Ω) and inherent phase margin eliminate oscillation risk even with 10 μF ceramic or tantalum capacitors directly at the cathode. This simplifies layout and improves reliability in high-vibration environments.

Can LM4040B41IDBZT operate across the full industrial temperature range?

Yes, LM4040B41IDBZT is characterized for operation from –40°C to +85°C (industrial grade, denoted by "I" suffix). Its electrical specifications-including ±0.2% initial accuracy, 100 ppm/°C tempco, and 35 μV_RMS noise-are guaranteed across this full range. The "Q" variant (e.g., LM4040B41IQDBZR) extends to +125°C for automotive under-hood use.

How does thermal hysteresis affect LM4040B41IDBZT in cyclic temperature environments?

LM4040B41IDBZT exhibits ≤0.08% thermal hysteresis-defined as the voltage difference measured at 25°C after cycling to –40°C versus after cycling to +125°C. In practice, this translates to ≤±3.3 mV hysteresis error in a 4.096 V reference, which remains within the ±0.2% initial tolerance band and is negligible for most 16-bit systems.

Is LM4040B41IDBZT compatible with lead-free reflow profiles?

Yes, LM4040B41IDBZT in the SOT-23 (DBZ) package is rated for standard lead-free reflow per JEDEC J-STD-020, with a peak temperature of 260°C. Its moisture sensitivity level (MSL) is 1, meaning it can be stored indefinitely at ≤30°C/85% RH without baking prior to assembly.