Texas Instruments LM4140CCM-1.2/NOPB

Overview

LM4140CCM-1.2/NOPB from Texas Instruments is a high-precision, low-noise, low-dropout series voltage reference with 1.25 V nominal output, 0.1% initial accuracy, 10 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 battery-powered instrumentation.

For engineers reviewing the LM4140CCM-1.2/NOPB datasheet, LM4140CCM-1.2/NOPB pinout, LM4140CCM-1.2/NOPB application, or LM4140CCM-1.2/NOPB equivalent, key selection considerations include its 1.25 V output voltage, SOIC-8 package, enable functionality, ultra-low 2.2 µV_PP (0.1–10 Hz) noise, and operation down to 1.8 V supply.

Technical Context

The LM4140CCM-1.2/NOPB uses EEPROM-trimmed CMOS DACs for curvature-corrected temperature compensation and output voltage trimming-enabling sub-bandgap 1.25 V output with 10 ppm/°C drift over 0°C to 70°C. Its P-channel pass transistor architecture supports low dropout and reverse current protection.

It operates in two functional modes: normal regulation (EN = VIN) and shutdown (EN = GND), achieving full output restoration in <200 µs. The device requires a mandatory 1 µF output capacitor for loop stability and transient response, with strict ESR constraints verified across tantalum, ceramic, and electrolytic types.

Key Specifications

Pinout & Package

LM4140CCM-1.2/NOPB is housed in an 8-pin SOIC (D) package (4.90 mm × 3.91 mm), with exposed pad not electrically connected. Ground pins (1, 4, 7, 8) must all be soldered to PCB ground plane for thermal and noise performance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with REF3012AIDBZR and ADR3412ARJZ-R7, the LM4140CCM-1.2/NOPB uniquely combines 1.25 V output, 0.1% accuracy, enable control, and sub-1 µA shutdown-making it the only option supporting precision, low-power, and dynamic power gating in compact portable designs.

Availability

LM4140CCM-1.2/NOPB is available at Aetrix Electronics and suitable for portable instrumentation, precision data acquisition, and battery-powered medical devices requiring stable component supply, long-lifecycle availability, and guaranteed traceable sourcing.

Supply support for LM4140CCM-1.2/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 company headquartered in Dallas, Texas, delivering analog and embedded processing solutions for industrial, automotive, and personal electronics markets.

The LM4140 product line was engineered to deliver sub-bandgap precision references with EEPROM-based trimming-targeting high-accuracy, low-power, and small-footprint applications in portable and battery-operated systems.

FAQ

What is the minimum input voltage required for stable operation of the LM4140CCM-1.2/NOPB?

The LM4140CCM-1.2/NOPB requires a minimum input voltage of 1.27 V (1.25 V output + 20 mV typical dropout) for stable regulation at 1 mA load. At higher loads or elevated temperatures, the dropout increases-up to 45 mV over 0°C to 70°C. Operation below 1.8 V supply is supported, making LM4140CCM-1.2/NOPB suitable for single-cell lithium or alkaline systems where headroom is constrained.

Does the LM4140CCM-1.2/NOPB require an output capacitor, and what type is recommended?

Yes, the LM4140CCM-1.2/NOPB mandates a 1 µF output capacitor between VREF (Pin 6) and GND (Pins 1/4/7/8) for loop stability and transient response. Solid tantalum capacitors (e.g., Kemet T491A105M010AS) are verified for optimal ESR range and stability. Ceramic capacitors may be used if ESR is ≥0.5 Ω and capacitance ≥0.2 µF; aluminum electrolytics are discouraged below 0°C due to ESR rise.

How does the enable pin function on the LM4140CCM-1.2/NOPB, and what happens during shutdown?

The EN pin (Pin 3) is active-high: driving it to ≥0.8×V_IN enables regulation; pulling it to GND disables output and reduces supply current to ≤1 µA. During shutdown, internal circuitry actively discharges the output capacitor to GND within microseconds-preventing floating reference states. The LM4140CCM-1.2/NOPB restores full 1.25 V output in <200 µs after enable assertion, with no startup overshoot.

What is the output noise specification of the LM4140CCM-1.2/NOPB, and how does it scale with output voltage?

The LM4140CCM-1.2/NOPB delivers 2.2 µV_PP (0.1–10 Hz) output noise for the 1.024 V version, and noise scales linearly with VREF. For the 1.25 V variant, noise is approximately 2.7 µV_PP. This ultra-low 1/f noise preserves effective resolution in high-precision applications such as 24-bit delta-sigma ADCs and laboratory-grade digital multimeters using LM4140CCM-1.2/NOPB as the reference source.

Is the LM4140CCM-1.2/NOPB pin-compatible with other members of the LM4140 family?

Yes, all LM4140 variants-including LM4140ACM-1.2/NOPB (A grade), LM4140BCM-1.2/NOPB (B grade), and LM4140CCM-1.2/NOPB (C grade)-share identical SOIC-8 pinout, electrical interface, and functional behavior. Only initial accuracy (0.1%) and temperature coefficient (10 ppm/°C for C grade) differ; no PCB layout changes are needed when upgrading or downgrading grades for cost or performance trade-offs.