STMicroelectronics LM4041CILT-1.2

Overview

LM4041CILT-1.2 from STMicroelectronics is a precision micropower shunt voltage reference delivering a stable 1.225 V output with ±0.5% initial accuracy at 25 °C, 40 µA typical operating current, and ≤100 ppm/°C temperature coefficient in SOT23-3L package. It serves as a compact, low-power voltage reference in battery-operated instrumentation and energy management systems.

For engineers reviewing the LM4041CILT-1.2 datasheet, LM4041CILT-1.2 pinout, LM4041CILT-1.2 application, or LM4041CILT-1.2 equivalent, key selection criteria include shunt reference stability under capacitive loads, ultra-low current operation across -40 to +85 °C, and SOT23-3L footprint compatibility for space-constrained PCB layouts.

Technical Context

The LM4041CILT-1.2 operates as a two-terminal shunt reference, regulating voltage by sinking variable current through its cathode while maintaining a precise 1.225 V drop between cathode and anode. Its internal bandgap core ensures high initial accuracy and low thermal drift without requiring external bias components.

Designed for direct replacement of Zener diodes in low-current applications, it achieves stable regulation with load currents from 40 µA to 12 mA and supports capacitive loads up to 1 µF without oscillation-enabling use in SMPS feedback loops and ADC reference buffers where layout-induced noise immunity matters.

Key Specifications

Pinout & Package

LM4041CILT-1.2 uses the SOT23-3L surface-mount package (3-pin, 2.9 mm × 2.8 mm × 1.12 mm), optimized for minimal board area and thermal performance in portable electronics.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLVH431ACDBVR and MAX6008AEUR+T, LM4041CILT-1.2 offers optimal balance of exact 1.225 V output, ultra-low 40 µA operation, and SOT23-3L footprint-making it preferred for space- and power-constrained fixed-reference applications where 1.25 V alternatives require circuit redesign.

Availability

LM4041CILT-1.2 is available at Aetrix Electronics and suitable for battery-operated equipment, switch mode power supply feedback, and instrumentation requiring stable component supply with guaranteed long-term availability.

Supply support for LM4041CILT-1.2 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, designing and manufacturing microcontrollers, analog ICs, power management devices, and MEMS sensors for industrial, automotive, and consumer markets.

The LM4041 product line delivers precision shunt references optimized for ultra-low-power, space-constrained applications including portable instrumentation, energy metering, and battery management systems.

FAQ

What is the maximum cathode voltage rating for LM4041CILT-1.2?

The absolute maximum cathode voltage is 8 V, as specified in the datasheet's Absolute Maximum Ratings table. Exceeding this voltage risks permanent device damage, even if current remains within limits. Designers must ensure the external series resistor limits cathode voltage to ≤8 V under all fault conditions, including open-load or transient surges.

Can LM4041CILT-1.2 drive a 1 µF capacitor directly without oscillation?

Yes-ST characterizes the LM4041CILT-1.2 as stable with ≥1 µF ceramic capacitive loads, as confirmed in Figure 4 (Output Impedance vs. Frequency) and the Applications section. This eliminates the need for series damping resistors in SMPS feedback paths or ADC reference decoupling, simplifying layout and reducing component count.

How does the 0.5% initial accuracy affect 12-bit ADC performance?

With a 1.225 V reference, ±0.5% accuracy equals ±6.1 mV error, corresponding to ±20 LSBs in a 12-bit system with 0–1.225 V full scale. This sets the absolute DC accuracy limit for measurements; system calibration can correct for this offset, but residual drift and noise determine dynamic performance.

Is the NC pin (Pin 3) required to connect to Anode in all layouts?

No-Pin 3 is internally unconnected and may be left floating. However, ST recommends connecting it to Anode in noisy environments to reduce PCB trace coupling into the reference node. This improves noise immunity without affecting electrical function, particularly in mixed-signal boards with switching regulators nearby.