Texas Instruments LM4040B82IDBZTG4

Overview

LM4040B82IDBZTG4 from Texas Instruments is a precision micropower shunt voltage reference with 8.192V nominal output, ±0.2% initial accuracy (B grade), 100ppm/°C temperature coefficient, 35μVRMS wideband noise, and stable operation from 45μA to 15mA cathode current. It serves as a compact, low-drift reference in high-resolution ADC biasing and sensor signal conditioning circuits.

For engineers reviewing the LM4040B82IDBZTG4 datasheet, LM4040B82IDBZTG4 pinout, LM4040B82IDBZTG4 application, or LM4040B82IDBZTG4 equivalent, key selection criteria include guaranteed 8.192V output tolerance over –40°C to 85°C, no-output-capacitor stability, SC-70/SOT-23 package compatibility, and low dynamic impedance for precision analog front-ends.

Technical Context

The LM4040B82IDBZTG4 operates as a two-terminal shunt reference, sinking cathode current (IZ) to maintain a precise 8.192V reverse breakdown voltage across its terminals. Its Zener-zap trimmed silicon design delivers tight initial tolerance and low thermal drift without external compensation.

It functions within a 45μA–15mA operating current range and exhibits 0.3Ω typical dynamic impedance at 1mA, enabling stable regulation under varying load conditions. The device is characterized for industrial temperature operation (–40°C to +85°C) and requires no output capacitor-remaining stable with all capacitive loads.

Key Specifications

Pinout & Package

LM4040B82IDBZTG4 is packaged in a 3-pin SOT-23 (DBZ) surface-mount package measuring 2.92mm × 1.30mm. Pin 1 is Cathode, Pin 2 is Anode, and Pin 3 is the NC (No Connect) terminal-intended to float or connect to Anode in high-EMI environments per TI recommendation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM4040C82IDBZT, the LM4040B82IDBZTG4 offers twice the initial accuracy for critical calibration points; versus REF3030AIDBZR, it provides exact 8.192V output without divider error or additional components-but trades higher tempco and noise.

Availability

LM4040B82IDBZTG4 is available at Aetrix Electronics and suitable for data-acquisition systems, energy infrastructure monitoring, and analog input modules requiring stable component supply, long-term calibration integrity, and industrial-temperature reliability.

Supply support for LM4040B82IDBZTG4 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 portable instrumentation, sensor interfaces, and industrial control systems where size, stability, and simplicity are critical.

FAQ

What is the output voltage tolerance of LM4040B82IDBZTG4 over temperature?

The LM4040B82IDBZTG4 has ±0.2% initial accuracy at 25°C and a maximum temperature coefficient of 100ppm/°C. Over the full industrial range (–40°C to +85°C), its total output variation is bounded by ±0.85% - calculated as ±0.2% ± (100ppm/°C × 65°C × 8.192V) - equating to ±69.6mV maximum deviation from nominal 8.192V. This value is confirmed in Section 6.19 of the TI datasheet.

Does LM4040B82IDBZTG4 require an output capacitor?

No, LM4040B82IDBZTG4 does not require an output capacitor. Its internal design ensures stability with all capacitive loads, including direct connection to ADC reference inputs or op-amp feedback nodes. This eliminates capacitor-related drift, aging, and board space - a key advantage over series references. The datasheet explicitly states "stable with all capacitive loads; no output capacitor required" in Section 1 Features.

What is the minimum cathode current needed for LM4040B82IDBZTG4 to regulate properly?

The LM4040B82IDBZTG4 requires a minimum cathode current (IZ,min) of 45μA at 25°C to maintain regulation within specification. At full temperature range (–40°C to +85°C), this increases to 80μA. Below this threshold, output voltage may deviate beyond tolerance limits. This parameter is specified in Table 6.19 (Electrical Characteristics for LM4040B82I) and applies directly to the LM4040B82IDBZTG4 variant.

How does the NC pin (Pin 3) function on LM4040B82IDBZTG4?

Pin 3 of LM4040B82IDBZTG4 is a No-Connect (NC) terminal with no internal connection. TI recommends leaving it floating under normal conditions, but connecting it to the Anode (Pin 2) in high-EMI environments - such as near transformers or switching regulators - to reduce noise coupling into the reference node. This guidance appears in Table 5-1 (Pin Functions) and Figure 5-1 of the official datasheet.

Is LM4040B82IDBZTG4 RoHS compliant and lead-free?

Yes, LM4040B82IDBZTG4 is RoHS compliant and lead-free. The "G4" suffix in the part number denotes TI's green packaging standard, which meets JEDEC JS-001 (HBM ±2000V) and RoHS Directive 2011/65/EU requirements. Full compliance documentation, including material declarations and test reports, is available through TI's Quality & Environmental section for orderable part LM4040B82IDBZTG4.