Texas Instruments LM4140BCMX-1.0/NOPB

Overview

LM4140BCMX-1.0/NOPB from Texas Instruments is a high-precision, low-noise, low-dropout series voltage reference with 1.024 V nominal output, 0.1% initial accuracy, 3 ppm/°C temperature coefficient (C grade), 20 mV typical dropout at 1 mA, and enable-controlled shutdown consuming ≤1 µA. It serves as a stable reference for precision ADCs, DACs, and portable instrumentation where ultra-low noise (2.2 µV_PP, 0.1–10 Hz) and sub-bandgap voltage operation are critical.

For engineers reviewing the LM4140BCMX-1.0/NOPB datasheet, LM4140BCMX-1.0/NOPB pinout, LM4140BCMX-1.0/NOPB application, or LM4140BCMX-1.0/NOPB equivalent, key selection considerations include its 1.024 V output compatibility with 12-bit systems, EEPROM-trimmed curvature correction for superior long-term stability (60 ppm over 1000 hours), and SOIC-8 package suitability for space-constrained industrial and medical PCB layouts.

Technical Context

The LM4140BCMX-1.0/NOPB employs a P-channel series pass transistor with internal EEPROM and CMOS DACs for real-time temperature coefficient curvature correction and output voltage trimming-enabling 3 ppm/°C drift performance without external components. Its architecture supports operation down to 1.8 V input (V_REF + 400 mV), making it suitable for single-cell Li-ion and coin-cell powered systems.

It features active output discharge during disable mode, fast turn-on (<200 µs), and robust load regulation (≤20 ppm/mA at 25°C). The device requires a mandatory 1 µF output capacitor for loop stability and transient response, with ESR constraints validated for tantalum, ceramic, and aluminum electrolytic types per TI's application guidance.

Key Specifications

Pinout & Package

LM4140BCMX-1.0/NOPB is housed in an 8-pin SOIC package (4.90 mm × 3.91 mm body size) with exposed pad not present. Pin functions are validated per TI SNVS053F Rev F datasheet.

Key Features

Applications

Equivalent & Alternatives

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

Compared with REF3012AIDBZR and ADR3410ARJZ-R7, the LM4140BCMX-1.0/NOPB delivers superior 3 ppm/°C stability and 2.2 µV_PP noise while maintaining ultra-low shutdown current-making it uniquely suited for portable, high-resolution measurement systems where both accuracy and energy efficiency are non-negotiable.

Availability

LM4140BCMX-1.0/NOPB is available at Aetrix Electronics and suitable for portable instrumentation, medical diagnostics, and industrial process control requiring stable component supply, long-lifecycle availability, and traceable sourcing.

Supply support for LM4140BCMX-1.0/NOPB 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, embedded processing, and connectivity technologies with over 90 years of innovation in precision analog design.

The LM4140 series was developed to deliver sub-bandgap voltage references with EEPROM-based trimming-targeting high-accuracy, low-power applications in portable test equipment, medical devices, and industrial sensors.

FAQ

What is the minimum input voltage required for stable operation of the LM4140BCMX-1.0/NOPB?

The LM4140BCMX-1.0/NOPB operates with a minimum input voltage of 1.8 V-just 760 mV above its 1.024 V output. This low dropout capability (20 mV typical at 1 mA) allows reliable regulation even as battery voltage declines in single-cell Li-ion or alkaline systems, ensuring uninterrupted reference stability throughout the discharge cycle of the LM4140BCMX-1.0/NOPB.

Does the LM4140BCMX-1.0/NOPB require an output capacitor, and if so, what type and value?

Yes-the LM4140BCMX-1.0/NOPB mandates a 1 µF output capacitor for loop stability and transient response. TI validates solid tantalum (e.g., Kemet T491A105M010AS), multilayer ceramic (e.g., Murata GRM42-6Y5V225Z16), and aluminum electrolytic types, provided ESR falls within specified ranges. Omitting or undersizing this capacitor risks oscillation and degraded noise performance in the LM4140BCMX-1.0/NOPB.

How does the enable pin function on the LM4140BCMX-1.0/NOPB, and what happens during shutdown?

The enable pin (Pin 3) controls LM4140BCMX-1.0/NOPB operation: driven high (≥0.8×V_IN) for normal mode, grounded for shutdown. In shutdown, output voltage drops to zero within microseconds, supply current falls to ≤1 µA, and internal circuitry actively discharges the output capacitor to ground-preventing residual voltage that could interfere with system reset sequences in the LM4140BCMX-1.0/NOPB.

What is the significance of the "C grade" designation in LM4140BCMX-1.0/NOPB?

The "C" in LM4140BCMX-1.0/NOPB denotes the highest accuracy grade: 0.1% initial output tolerance and 3 ppm/°C temperature coefficient over 0–70°C. This grade uses enhanced EEPROM/DAC trimming during final test to achieve tighter parametric distribution than A (10 ppm/°C) or B (6 ppm/°C) grades-making the LM4140BCMX-1.0/NOPB ideal for metrology-grade applications demanding minimal calibration overhead.

Can the LM4140BCMX-1.0/NOPB drive a 10 kΩ load directly, and what is its maximum output current?

Yes-the LM4140BCMX-1.0/NOPB can directly drive a 10 kΩ load (102.4 µA at 1.024 V) with negligible error, as its load regulation is specified at ≤20 ppm/mA. Its absolute maximum continuous output current is ±8 mA, verified across temperature. For heavier loads (e.g., >1 mA), TI recommends verifying dropout margin and thermal rise-especially in compact SOIC layouts where the LM4140BCMX-1.0/NOPB's 119.3°C/W R_θJA may limit sustained output.