STMicroelectronics LIS302ALB

Overview

LIS302ALB from STMicroelectronics is a miniaturized 3-axis analog-output MEMS accelerometer with ±2g full-scale range, ratiometric voltage outputs (Voutx/Vouty/Voutz), and integrated multiplexer for single-channel ADC interfacing. It operates from 3.0–3.6V, consumes ~0.65mA in active mode, supports self-test and power-down modes, and delivers 2.0kHz bandwidth - used in mobile terminal motion sensing, free-fall detection, and inertial navigation systems.

For engineers reviewing the LIS302ALB datasheet, LIS302ALB pinout, LIS302ALB application, or LIS302ALB equivalent, key selection criteria include its ratiometric analog output architecture, LGA-14 package footprint, ±2g measurement range, embedded self-test capability, and multiplexed output switching via S0/S1 control pins.

Technical Context

The LIS302ALB integrates a surface-micromachined capacitive sensing element with a fully differential CMOS interface featuring Correlated Double Sampling (CDS) to suppress offset and 1/f noise. Its analog outputs are ratiometric to Vdd, ensuring supply-independent zero-g level (Vdd/2 ±6%) and sensitivity (0.145×Vdd ±5% V/g).

It implements three independent sample-and-hold circuits per axis, plus an on-chip 2-bit multiplexer (S0/S1 controlled) that routes Voutx, Vouty, Voutz, or Aux_in to the shared Vout pin. Bandwidth is set externally via load capacitance (Cload ≥2.5nF) across the 32kΩ output impedance, enabling configurable low-pass filtering down to DC.

Key Specifications

Pinout & Package

Package: LGA-14 (3×5×0.9mm Thin Land Grid Array), RoHS-compliant ECOPACK®.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 3-axis analog-output accelerometer applications.

Compared with ADXL335 and LIS331DLH, the LIS302ALB uniquely combines factory-calibrated analog outputs, hardware multiplexing, and self-test in a 3×5mm LGA - making it optimal for cost-sensitive, analog-centric motion-sensing systems needing guaranteed out-of-box accuracy and minimal external components.

Availability

LIS302ALB is available at Aetrix Electronics and suitable for mobile terminal orientation sensing, gaming motion input, and free-fall data protection requiring stable component supply and long-lifecycle support.

Supply support for LIS302ALB 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 specializing in MEMS sensors, microcontrollers, and power management ICs, with manufacturing and R&D facilities across Europe, Asia, and the Americas.

The LIS302ALB belongs to ST's "piccolo" family of ultra-compact analog accelerometers - designed specifically for space-constrained portable electronics where low power, analog simplicity, and proven shock resilience are critical.

FAQ

What is the purpose of the Aux_in pin on the LIS302ALB?

The Aux_in pin serves as an auxiliary analog input that can be routed to the shared Vout pin when the S0 and S1 control bits are both high (11). This allows integration of a secondary analog sensor-such as a temperature or voltage monitor-without adding extra ADC channels. It is not internally conditioned or scaled; its signal passes directly through the multiplexer with the same 32kΩ output impedance as the accelerometer channels.

How does the ratiometric output affect ADC conversion accuracy?

Because the LIS302ALB's zero-g level and sensitivity scale linearly with Vdd (e.g., Voff = Vdd/2 ±6%, So = 0.145×Vdd V/g), using the same Vdd as the ADC reference eliminates supply-induced gain and offset errors. This ratiometric matching ensures that variations in supply voltage do not degrade measurement accuracy - a key advantage over fixed-reference analog sensors in battery-powered systems.

Can the LIS302ALB operate below 3.0V?

No - the absolute minimum supply voltage is 3.0V per Table 3, and the device is factory calibrated at 3.3V. Although the absolute maximum rating allows down to 2.16V, ST specifies guaranteed operation only within 3.0–3.6V. Operation below 3.0V may cause undefined behavior, reduced sensitivity, or failure to enter power-down mode reliably.

Why is a minimum 2.5nF capacitor required on each analog output?

The 2.5nF minimum load capacitance ensures stable operation of the internal 32kΩ output impedance driving circuitry. Lower capacitance risks oscillation or overshoot due to phase margin degradation. This capacitor also forms the dominant pole of the external RC filter, setting the anti-aliasing cutoff frequency - critical for accurate sampling at the intended bandwidth (e.g., 100nF yields ~50Hz cutoff).