NXP Semiconductors MMA6281QT

Overview

MMA6281QT from Freescale Semiconductor is a two-axis (X/Z) capacitive micromachined accelerometer with factory-trimmed ±2.5g/±3.3g/±6.7g/±10g selectable full-scale range, 500 μA typical supply current, and integrated signal conditioning with 1-pole switched-capacitor low-pass filter. It operates from 2.2 V to 3.6 V and delivers ratiometric analog voltage outputs for motion sensing in battery-powered portable electronics.

For engineers reviewing the MMA6281QT datasheet, MMA6281QT pinout, MMA6281QT application, or MMA6281QT equivalent, this device supports tilt compensation in e-compass systems, impact event recording in black-box applications, and motion-triggered text scrolling in PDAs - all while enabling ultra-low-power operation via Sleep Mode (3 μA).

Technical Context

The MMA6281QT integrates dual surface-micromachined g-cells with an ASIC performing capacitance-to-voltage conversion, temperature-compensated gain scaling, and digital control of sensitivity via g-Select logic pins. Its internal 11 kHz sampling clock drives a switched-capacitor filter whose cutoff frequency is set by g-range selection (e.g., 350 Hz in 2.5g mode).

Signal path includes factory-trimmed zero-g offset (1.65 V at 25°C, VDD = 3.3 V), ±1.0% FSO nonlinearity, and cross-axis sensitivity ≤5.0%. The device uses ratiometric output architecture - both offset and sensitivity scale linearly with VDD - enabling robust interfacing with microcontroller ADCs without external reference voltage.

Key Specifications

Pinout & Package

Package: 16-lead QFN (6 mm × 6 mm × 1.45 mm), Case No. 1622-02, tray packaging. Exposed thermal pad (flag) is internally connected to VSS but not recommended for soldering in consumer applications.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MMA8451Q and ADXL322, the MMA6281QT uniquely balances ultra-low active and sleep current, four factory-calibrated g-ranges via simple logic inputs, and ratiometric analog outputs - making it optimal for cost-sensitive, battery-constrained portable devices requiring flexible motion sensing without digital interface overhead.

Availability

MMA6281QT is available at Aetrix Electronics and suitable for portable tilt monitoring, impact event logging, and motion-triggered user interfaces requiring stable component supply across industrial temperature grades and long production lifecycles.

Supply support for MMA6281QT 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

Freescale Semiconductor (now part of NXP Semiconductors) was a leading designer of embedded processors and sensors, known for high-reliability automotive and industrial-grade analog/mixed-signal ICs.

The MMA6281QT belongs to Freescale's micromachined accelerometer product line, engineered specifically for low-cost, low-power motion sensing in battery-operated consumer and industrial portable equipment.

FAQ

What is the operating voltage range for the MMA6281QT?

The MMA6281QT operates from 2.2 V to 3.6 V. Within this range, it functions as a fully calibrated linear accelerometer; operation outside these limits may yield linear output but without guaranteed calibration accuracy. The device's ratiometric architecture ensures that both zero-g offset and sensitivity scale proportionally with VDD, simplifying integration with microcontrollers sharing the same supply rail.

How does the g-Select feature work on the MMA6281QT?

The g-Select feature on the MMA6281QT uses two logic inputs (pins 1 and 2) to select among four full-scale ranges: ±2.5g, ±3.3g, ±6.7g, or ±10g. The mapping is defined in Table 3 of the datasheet (e.g., g-Select1=0, g-Select2=0 selects 2.5g). If left unconnected, g-Select1 defaults low via internal pull-down, fixing the MMA6281QT in 2.5g mode (480 mV/g sensitivity) without external components.

What is the Sleep Mode current consumption of the MMA6281QT?

The MMA6281QT draws 3 μA typical current in Sleep Mode, activated by applying a logic low to pin 12 (Sleep Mode). In this state, analog outputs are disabled and internal circuitry enters ultra-low-power standby. Recovery to full operation takes less than 2 ms, supporting motion-triggered wake-up architectures in battery-powered devices using the MMA6281QT.

Does the MMA6281QT require external components for filtering or biasing?

No, the MMA6281QT requires no external components for basic operation. Its onboard switched-capacitor filter sets bandwidth per g-range (e.g., 350 Hz in 2.5g mode), and zero-g offset is factory-trimmed. A 0.1 µF ceramic capacitor on VDD is recommended for decoupling, and 1 kΩ + 0.1 µF RC filters on XOUT/ZOUT suppress clock feedthrough - but neither is mandatory for functional operation of the MMA6281QT.

What is the package type and thermal pad configuration of the MMA6281QT?

The MMA6281QT uses a 16-pin QFN package (6 mm × 6 mm × 1.45 mm, Case 1622-02) with an exposed die pad (flag) internally connected to VSS. Freescale explicitly recommends *not* soldering down the flag or the four corner ground pads for consumer applications to avoid mechanical stress-induced reliability issues - a critical layout constraint for successful MMA6281QT integration.