Texas Instruments LM4040C50ILPE3

Overview

LM4040C50ILPE3 from Texas Instruments is a precision micropower shunt voltage reference with 5.0V nominal output, ±0.5% initial accuracy (C 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 analog-to-digital converters and sensor signal conditioning circuits for industrial field transmitters.

For engineers reviewing the LM4040C50ILPE3 datasheet, LM4040C50ILPE3 pinout, LM4040C50ILPE3 application, or LM4040C50ILPE3 equivalent, key selection criteria include its guaranteed 5.0V output tolerance over –40°C to 85°C, no-output-capacitor requirement, SC-70-5 package footprint, and compatibility with high-EMI environments via optional pin-3 connection.

Technical Context

The LM4040C50ILPE3 operates as a two-terminal shunt reference, sinking cathode current (IZ) to maintain a precise 5.0V reverse breakdown voltage across its cathode-anode terminals. Its Zener-zap trimmed bandgap architecture delivers stable output under varying load currents and temperatures without external compensation.

It features low dynamic impedance (≤0.9Ω at 1mA), thermal hysteresis of 0.08%, and long-term stability of 120ppm after 1000 hours - enabling high-accuracy voltage scaling in portable and automotive-grade data acquisition systems where supply headroom is constrained.

Key Specifications

Pinout & Package

LM4040C50ILPE3 is packaged in a 5-pin SC-70 (DCK) package measuring 2.00mm × 1.25mm. Pin 1 = Anode (ground reference), Pin 2 = Cathode (output voltage node), Pins 4–5 = No Internal Connection (NC), Pin 3 = NC but recommended floating or tied to anode in high-EMI layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TL4050C50IDBZR, LM4040C50ILPE3 offers higher current capability and EMI-hardened pin-3 option; compared with ADR3450ARJZ-R7, it trades tighter initial accuracy for lower cost and proven robustness in industrial field deployments.

Availability

LM4040C50ILPE3 is available at Aetrix Electronics and suitable for industrial field transmitters, portable data loggers, and automotive cabin sensor interfaces requiring stable component supply with traceable lot history and extended lifecycle support.

Supply support for LM4040C50ILPE3 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 power management ICs, with decades of heritage in precision reference design.

The LM4040 series was developed to deliver cost-optimized, micropower shunt references for space- and power-constrained industrial and automotive signal chains - balancing accuracy, stability, and ease of use without external components.

FAQ

What is the maximum cathode current rating for LM4040C50ILPE3?

The absolute maximum cathode current for LM4040C50ILPE3 is 25mA per Absolute Maximum Ratings, but the recommended operating condition specifies up to 15mA for reliable performance across the full –40°C to +85°C temperature range. Exceeding 15mA may require thermal derating based on PCB copper area and ambient conditions. LM4040C50ILPE3 must be operated within this limit to maintain specified accuracy and long-term stability.

Does LM4040C50ILPE3 require an output capacitor?

No, LM4040C50ILPE3 is stable with all capacitive loads and does not require an output capacitor for operation - a key advantage over many series references. This simplifies layout, reduces component count, and eliminates capacitor-related aging or ESR effects. LM4040C50ILPE3 achieves this via internal compensation optimized for shunt topology and wide current range.

What is the purpose of Pin 3 on LM4040C50ILPE3?

Pin 3 on LM4040C50ILPE3 is a no-internal-connection (NC) terminal, but Texas Instruments recommends leaving it floating or connecting it to the anode (Pin 1) in high-EMI environments - such as near switching power supplies or motor drivers - to reduce noise coupling into the reference node. LM4040C50ILPE3's Pin 3 provides a deliberate shield path absent in 3-pin alternatives.

How does the temperature coefficient affect LM4040C50ILPE3 accuracy over its operating range?

With a maximum temperature coefficient of 100ppm/°C, LM4040C50ILPE3 contributes ≤±0.525% additional error over its –40°C to +85°C range beyond its ±0.5% initial tolerance. This yields a worst-case total output variation of ±1.025% (±51.25mV at 5.0V), verified in the LM4040C50I electrical characteristics table. LM4040C50ILPE3 maintains this spec without external trimming.

Is LM4040C50ILPE3 suitable for automotive applications?

LM4040C50ILPE3 is qualified for industrial temperature range (–40°C to +85°C), making it suitable for non-safety-critical automotive cabin applications like HVAC sensors and infotainment subsystems. It is not AEC-Q200 qualified; for under-hood or safety-critical use, TI's LM4040-Q1 variants (e.g., LM4040C50QDBZRQ1) with extended –40°C to +125°C rating and automotive qualification should be selected instead of LM4040C50ILPE3.