STMicroelectronics LIS3MDLTR

Overview

LIS3MDLTR from STMicroelectronics is an ultralow-power, high-performance 3-axis digital magnetometer IC with user-selectable full-scale ranges of ±4/±8/±12/±16 gauss, 16-bit output resolution, I²C/SPI dual-interface support, and integrated self-test functionality. It operates from 1.9 V to 3.6 V supply voltage with independent 1.8 V I/O rail and delivers RMS noise as low as 3.2 mgauss in ultrahigh-performance mode - enabling precision electronic compassing in handheld navigation devices.

For engineers reviewing the LIS3MDLTR datasheet, LIS3MDLTR pinout, LIS3MDLTR application, or LIS3MDLTR equivalent, key selection criteria include magnetic sensitivity (6842 LSB/gauss at ±4 G), zero-gauss offset stability (±1 gauss), interrupt-driven field detection, low-power operation (40 µA in LP mode), and LGA-12L package compatibility with space-constrained PCB layouts.

Technical Context

The LIS3MDLTR integrates a triaxial anisotropic magnetoresistive (AMR) sensing element with on-chip signal conditioning, 16-bit sigma-delta ADC, and programmable gain amplifier. Its factory-trimmed sensitivity and zero-gauss offset are stored in nonvolatile memory and auto-loaded at power-up, eliminating need for system-level calibration.

It supports two serial interfaces via shared pins: I²C (100 kHz / 400 kHz) with configurable slave address (0x38/0x3C or 0x39/0x3D), and SPI in 3-wire or 4-wire mode controlled by CS and SIM bit. Interrupt generation (INT) and data-ready (DRDY) signals enable event-driven firmware architectures without polling overhead.

Key Specifications

Pinout & Package

The LIS3MDLTR is housed in a 2 mm × 2 mm × 0.7 mm LGA-12L (land grid array) package with exposed pad for thermal and electrical grounding. Pin numbering follows top-view orientation per DS9463 Rev 7.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 3-axis magnetometer applications.

Compared with AK09918C and BMM150, the LIS3MDLTR uniquely combines factory-trimmed calibration retention, dual-interface flexibility, and sub-4 mgauss noise performance - making it optimal for automotive-qualified compass modules and industrial position sensors requiring long-term stability without recalibration.

Availability

LIS3MDLTR is available at Aetrix Electronics and suitable for smartphone electronic compasses, industrial current sensing systems, and wearable fitness trackers requiring stable component supply across multi-year production cycles.

Supply support for LIS3MDLTR 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, Switzerland, designing and manufacturing microcontrollers, sensors, power ICs, and analog components for industrial, automotive, and consumer markets.

The LIS3MDL product line targets high-accuracy magnetic sensing applications including electronic compassing, current detection, and position feedback - emphasizing ultralow power, factory calibration, and robust EMC performance in compact LGA packages.

FAQ

What is the function of the C1 pin (Pin 4) on the LIS3MDLTR?

Pin 4 (C1) connects to a mandatory 100 nF capacitor to ground, which stabilizes the internal bias circuitry of the magnetic sensor. This capacitor directly reduces zero-gauss offset drift and improves measurement repeatability over temperature and time. Omitting or undersizing C1 causes increased noise and calibration instability, as confirmed in DS9463 Section 4.1.

How does the LIS3MDLTR handle I/O voltage mismatch between core and interface logic?

The LIS3MDLTR uses separate Vdd (1.9–3.6 V) and Vdd_IO (1.71–1.8 V) supplies, allowing independent powering of analog sensing and digital I/O circuits. This decoupling prevents digital switching noise from modulating the magnetic measurement path and enables direct interfacing with 1.8 V microcontrollers even when the core runs at 3.3 V - a feature verified in Table 4 of DS9463.

Can the LIS3MDLTR operate in SPI 3-wire mode without external pull-up resistors?

Yes - in SPI 3-wire mode (enabled by setting SIM=1 in CTRL_REG3), the SDO/SA1 pin becomes dedicated output and does not require pull-up resistors. However, SCL/SPC and SDA/SDI/SDO lines still need appropriate termination: SCL/SPC requires no pull-up in SPI (master-driven), but SDA/SDI/SDO must be pulled up only if shared with I²C; otherwise, they remain actively driven.

What is the impact of exceeding the 50 gauss magnetic disturbance field specification?

Exposure to fields >50 gauss degrades zero-gauss offset accuracy beyond ±1 gauss, causing permanent residual offset shifts that persist after field removal. This effect is documented in Table 2 (DF parameter) and verified in application note AN4602 - making mechanical shielding and layout separation from motors/speakers essential in compass-grade designs.