Texas Instruments LM4128DMFX-4.1/NOPB

Overview

LM4128DMFX-4.1/NOPB from Texas Instruments is a precision micropower series voltage reference in 5-pin SOT-23 package, delivering 4.096 V output with ±0.5% initial accuracy (C-grade), 100 ppm/°C temperature coefficient, and 60 µA supply current. It features an enable pin for 3 µA shutdown mode and supports up to 20 mA output current, making it suitable for high-resolution ADC/DAC biasing in portable instrumentation.

For engineers reviewing the LM4128DMFX-4.1/NOPB datasheet, LM4128DMFX-4.1/NOPB pinout, LM4128DMFX-4.1/NOPB application, or LM4128DMFX-4.1/NOPB equivalent, key selection criteria include dropout voltage (≤400 mV at 10 mA), load regulation (25–120 ppm/mA), 0.1–10 Hz noise (350 µV_PP), and stability with capacitive loads up to 10 µF without external compensation.

Technical Context

The LM4128DMFX-4.1/NOPB implements a band-gap-derived series reference architecture with internal enable control logic and thermal compensation circuitry. Its design eliminates need for external stabilization capacitors while maintaining stability across –40°C to +125°C junction temperature range and with output capacitance up to 10 µF.

It operates with input voltage as low as V_REF + 400 mV (i.e., ≥4.496 V at 10 mA load) and delivers 4.096 V output with guaranteed long-term stability of 50 ppm over 1000 hours. The enable pin accepts logic-level inputs (V_IL ≤35% V_IN, V_IH ≥65% V_IN) and transitions the device between active (60 µA I_Q) and shutdown (3–7 µA I_{Q_SD}) states.

Key Specifications

Pinout & Package

LM4128DMFX-4.1/NOPB uses the 5-pin SOT-23 (DBV) package - compact (2.9 mm × 1.6 mm × 1.15 mm), surface-mount, RoHS-compliant, and rated for –40°C to +125°C junction temperature. Pin 1 is NC (no connect), requiring no PCB trace or solder connection.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM4128DMFX-4.1/NOPB, REF3040AIDBZR offers tighter accuracy and lower drift but sacrifices integrated enable functionality, while MAX6029AEUR+T achieves lower power consumption at the expense of junction temperature range - making LM4128DMFX-4.1/NOPB optimal for industrial and automotive applications demanding both precision and wide-temperature enable control.

Availability

LM4128DMFX-4.1/NOPB is available at Aetrix Electronics and suitable for portable instrumentation, industrial sensor transmitters, medical analog front-ends, and automotive cabin modules requiring stable component supply with guaranteed long-term availability.

Supply support for LM4128DMFX-4.1/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 and embedded processing technologies, with decades of expertise in precision analog ICs and industrial-grade reliability.

The LM4128 product line delivers micropower, low-drift series voltage references optimized for space-constrained, battery-operated, and high-accuracy measurement systems across industrial, medical, and automotive domains.

FAQ

What is the output voltage tolerance and grade designation for LM4128DMFX-4.1/NOPB?

The LM4128DMFX-4.1/NOPB is a C-grade device with ±0.5% initial output voltage accuracy at 25°C, corresponding to a 4.096 V nominal output with ±20.5 mV absolute tolerance. This grade is confirmed in the Electrical Characteristics table for LM4128-4.1 under "LM4128C-4.1" row, and applies across the full –40°C to +125°C operating temperature range per TI SNVS475E datasheet revision April 2013.

Does LM4128DMFX-4.1/NOPB require an input capacitor, and what is the minimum value?

Yes, LM4128DMFX-4.1/NOPB requires an input capacitor (C_IN). When no output capacitor is used, C_IN must be ≥0.1 µF ceramic (X5R/X7R). If an output capacitor (C_OUT) is present, C_IN must be ≥C_OUT. This requirement is explicitly stated in the APPLICATION INFORMATION section of the TI SNVS475E datasheet and is mandatory for stable operation and noise suppression.

What is the maximum load current and dropout voltage specification for LM4128DMFX-4.1/NOPB?

The LM4128DMFX-4.1/NOPB supports up to 20 mA output current. Its dropout voltage is specified as ≤400 mV at 10 mA load current, meaning VIN must be ≥4.496 V to maintain regulation. This value is confirmed in the Electrical Characteristics table for LM4128-4.1 under "VIN – VREF" parameter, with test condition I_LOAD = 10 mA.

How does the enable pin function on LM4128DMFX-4.1/NOPB, and what are its voltage thresholds?

The enable pin (Pin 3) of LM4128DMFX-4.1/NOPB is active-high with logic thresholds referenced to VIN: V_IL ≤35% VIN disables the output (entering 3–7 µA shutdown), and V_IH ≥65% VIN enables regulation. The internal pull-up current is ~2 µA, allowing direct connection to VIN if always-on operation is desired. These values are defined in the Electrical Characteristics table under "VIL" and "VIH" parameters.

Is LM4128DMFX-4.1/NOPB qualified for automotive applications?

No - LM4128DMFX-4.1/NOPB is the commercial-grade version. Automotive-qualified variants are designated LM4128xQ (e.g., LM4128CQMF-4.1/NOPB), which are AEC-Q100 Grade 1 qualified and manufactured on an automotive-grade flow. The "D" in LM4128DMFX-4.1/NOPB indicates C-grade performance (±0.5%), not automotive qualification; this distinction is clearly documented in TI's PACKAGE OPTION ADDENDUM and datasheet feature list.