Texas Instruments LM4040C20ILPE3

Overview

LM4040C20ILPE3 from Texas Instruments is a precision 2.048V shunt voltage reference in SOT-23-3 package, rated for industrial temperature range (–40°C to +85°C), with ±0.5% initial accuracy, 100ppm/°C temperature coefficient, 35μVRMS wideband noise, and stable operation down to 45μA cathode current. It serves as a compact, low-power voltage reference in analog-to-digital converter biasing and sensor signal conditioning circuits.

For engineers reviewing the LM4040C20ILPE3 datasheet, LM4040C20ILPE3 pinout, LM4040C20ILPE3 application, or LM4040C20ILPE3 equivalent, this page delivers verified electrical specifications, validated pin functions, confirmed thermal and noise performance, and real-world implementation guidance for high-accuracy data acquisition systems.

Technical Context

The LM4040C20ILPE3 operates as a two-terminal shunt reference, sinking cathode current (IZ) to maintain a stable 2.048V reverse breakdown voltage across its terminals. Its Zener-zap trimmed silicon design achieves tight initial tolerance without external components, and its low dynamic impedance (≤0.9Ω at 1mA) ensures minimal output variation under load transients.

It requires no output capacitor and remains stable with all capacitive loads-enabling direct integration into space-constrained PCB layouts. The device's thermal hysteresis is specified at 0.08%, and long-term stability is 120ppm over 1000 hours at 25°C, supporting reliable performance in field-deployed instrumentation.

Key Specifications

Pinout & Package

SOT-23-3 (DBZ) package: 2.92mm × 1.30mm footprint, surface-mount, lead-free, RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TL4050C20IDBZR and ADR3420ARJZ-R7, LM4040C20ILPE3 offers optimal balance of micropower operation (45μA), industry-standard SOT-23-3 footprint, and proven reliability in field-transmitter deployments-making it the preferred choice for cost-sensitive, space-constrained industrial analog signal chains.

Availability

LM4040C20ILPE3 is available at Aetrix Electronics and suitable for industrial analog input modules, portable data loggers, field transmitter signal conditioning, and energy infrastructure metering requiring stable component supply, long-lifecycle support, and consistent parametric performance across production batches.

Supply support for LM4040C20ILPE3 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 reference design and high-reliability industrial ICs.

The LM4040 series was developed specifically for high-accuracy, low-power shunt reference applications in data acquisition, sensor interfacing, and industrial automation-emphasizing ease of use, minimal external components, and robust thermal performance.

FAQ

What is the maximum operating temperature range for LM4040C20ILPE3?

The LM4040C20ILPE3 is characterized for operation from –40°C to +85°C (industrial temperature range). It is not rated for extended temperature operation up to 125°C-that specification applies only to the Q-grade variants such as LM4040C20Q. Using LM4040C20ILPE3 beyond +85°C may result in degraded accuracy and accelerated long-term drift.

Can LM4040C20ILPE3 be used without an output capacitor?

Yes, LM4040C20ILPE3 is explicitly designed to operate stably with all capacitive loads and requires no output capacitor. This is confirmed in the datasheet's "Features" and "Description" sections. Adding a capacitor is unnecessary and may introduce instability in certain high-frequency noise environments-TI recommends leaving the output unfiltered unless EMI testing indicates otherwise.

What is the minimum cathode current required for LM4040C20ILPE3 to regulate properly?

The LM4040C20ILPE3 requires a minimum cathode current of 45μA (typical) at 25°C to maintain regulation within specification. Over the full –40°C to +85°C range, the guaranteed minimum is 80μA. Operating below this threshold risks loss of regulation and increased output voltage error-designers must size the series resistor accordingly based on worst-case supply voltage and load conditions.

How does the 0.5% initial accuracy of LM4040C20ILPE3 impact 12-bit ADC performance?

With a 2.048V output, LM4040C20ILPE3's ±0.5% initial error equals ±10.24mV, which corresponds to ±20 LSBs in a 12-bit system (LSB = 0.5mV). This means the reference alone can introduce up to ±20 counts of full-scale error before gain/offset calibration. For high-fidelity measurements, system-level calibration is recommended-but the tight tolerance still enables single-point correction in most industrial applications.

Is LM4040C20ILPE3 pin-compatible with other LM4040 variants like LM4040A20ILPE3?

Yes, LM4040C20ILPE3 shares identical SOT-23-3 (DBZ) pinout and package dimensions with all LM4040x20I variants-including LM4040A20ILPE3 and LM4040B20ILPE3. Pin 1 is Cathode, Pin 2 is Anode, and Pin 3 is NC. However, accuracy grade differences mean direct substitution affects system-level tolerance; replacing C-grade with A-grade improves initial accuracy but does not alter pin function or layout.