MMA6231Q - ±10g Dual-Axis Micromachined Accelerometer | NXP
MPN: MMA6231Q ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $5.5 | $5.50 |
| 10 | $5 | $50.00 |
| 100 | $4.45 | $445.00 |
| 500 | $3.95 | $1,975.00 |
| 1,000 | $3.6 | $3,600.00 |
MMA6231Q Overview
A micromachined accelerometer is a MEMS (Micro-Electro-Mechanical Systems) device that converts acceleration into a measurable electrical signal using a suspended proof mass whose capacitance changes under inertial force; signal conditioning ASICs then convert this into an analog voltage proportional to acceleration. The MMA6231Q belongs to the broader family of motion and position sensors, sitting under inertial sensors → accelerometers → surface-mount MEMS accelerometers. The device is qualified for lead-free and RoHS-compliant assembly, with self-test capability verifying the full signal path.
Key features include a ±10 g full-scale range, typical 120 mV/g sensitivity, 300 Hz bandwidth (with internal low-pass filter cut-off settable within this range), a wide supply range of 2.7 V to 3.6 V, very low current consumption (typically a few mA during operation), and an internal self-test mechanism that electronically deflects the proof mass to validate sensor and ASIC functionality. The factory-trimmed architecture eliminates per-board calibration for many consumer and industrial tilt, vibration and motion-detect applications.
At its core, the MMA6231Q uses a capacitive bridge sensing cell whose differential output is amplified, filtered and offset-adjusted by on-chip CMOS analog front-end circuitry. The 1-pole RC low-pass filter limits high-frequency mechanical and electrical noise. Because zero-g offset, sensitivity and filter cut-off are laser-trimmed at the factory, part-to-part variation is significantly reduced compared to discrete MEMS solutions requiring external calibration.
Typical applications include tilt and inclination sensing, vibration monitoring, appliance and industrial equipment motion detection, automotive security systems, consumer electronics orientation, and general-purpose dual-axis motion and position sensing. The small 6 × 6 mm QFN package is well suited to compact PCB layouts where board space is constrained.
When designing with this part, place the recommended 0.1 µF supply-decoupling capacitor as close to the VDD and GND pins as possible to minimize digital noise coupling. For accurate tilt measurements, mount the device on a vibration-isolated section of the board so that high-frequency PCB vibrations do not alias into the measurement band.
This page synthesizes distributor availability, drop-in alternatives, application examples and design notes beyond the manufacturer datasheet to accelerate component evaluation and PCB redesign tasks.
Drop-in alternatives for MMA6231Q — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
MMA6233Q
✅ Drop-In📋 Reference alternative (not in catalog)
MMA6801KW
✅ Drop-In📋 Reference alternative (not in catalog)
MMA6821KW
✅ Drop-In📋 Reference alternative (not in catalog)
MMA6231Q Maximum Ratings & Electrical Characteristics
| Sensor Type | Accelerometer |
| Sensing Axes | X, Y (dual axis) |
| Acceleration Range | ±10 g |
| Sensitivity | 120 mV/g (typical); 111 to 129 mV/g across parts |
| Supply Voltage | 2.7 V to 3.6 V (3.3 V typical) |
| Bandwidth | 300 Hz (1-pole low-pass filter) |
| Output Type | Analog voltage |
| Operating Temperature | -20 °C to +85 °C |
| Package | 16-pin QFN-EP (6 mm × 6 mm) with exposed pad |
| Mounting Type | Surface Mount |
| Self-Test | Yes (internal electronic self-test) |
| Zero-g Offset | Factory trimmed (no external components required) |
| RoHS Status | Compliant |
| Lead-Free Status | Lead Free |
| Architecture | Capacitive micromachined (MEMS) with on-chip ASIC signal conditioning |
MMA6231Q Pin Configuration
| Pin 1 | VDD — Power supply (2.7 V to 3.6 V); place 0.1 µF decoupling as close as possible |
| Pin 2 | GND — Ground reference for the ASIC and MEMS sensing element |
| Pin 3 | X_OUT — Analog X-axis acceleration output (≈120 mV/g) |
| Pin 4 | Y_OUT — Analog Y-axis acceleration output (≈120 mV/g) |
| Pin 5 | ST — Self-test input (logic high applies electrostatic deflection to proof mass) |
| Pin 6 | NC — Not connected (no internal bond) |
| Pin 7 | NC — Not connected (no internal bond) |
| Pin 8 | NC — Not connected (no internal bond) |
| Pin 9 | NC — Not connected (no internal bond) |
| Pin 10 | NC — Not connected (no internal bond) |
| Pin 11 | NC — Not connected (no internal bond) |
| Pin 12 | NC — Not connected (no internal bond) |
| Pin 13 | NC — Not connected (no internal bond) |
| Pin 14 | NC — Not connected (no internal bond) |
| Pin 15 | NC — Not connected (no internal bond) |
| Pin 16 | NC — Not connected (no internal bond) |
| Pin EP | GND_PAD — Exposed thermal pad on bottom of package; solder to PCB ground plane |
Typical Applications
MMA6231Q is suitable for 6 applications: Tilt and Inclination Sensing, Vibration Monitoring in Industrial Equipment, Consumer Electronics Orientation Detection, Appliance Motion Detection (Washers, Dryers, Refrigerators), Automotive Security and Tamper Detection, General Dual-Axis Motion and Position Sensing.
Tilt and Inclination Sensing
The MMA6231Q's ±10 g full-scale range, factory-trimmed zero-g offset (no calibration) and 120 mV/g sensitivity make it well-suited for static and dynamic tilt sensing on flat-surfaced PCBs. The 1-pole 300 Hz low-pass filter limits high-frequency noise that would otherwise corrupt slow tilt measurements. In a typical application, the device is mounted on a vibration-isolated portion of the board, powered from a regulated 3.3 V rail, with the X and Y outputs read by an MCU ADC. Designers can resolve sub-degree tilt angles over the ±1 g portion of the range. The factory-trimmed offset removes the need for per-board calibration, cutting bill of materials and assembly time. Compared with discrete MEMS solutions, the MMA6231Q reduces external component count to just a single decoupling capacitor.
Recommended
Vibration Monitoring in Industrial Equipment
The MMA6231Q's 300 Hz internal 1-pole low-pass filter covers the dominant frequency content of most industrial machinery vibration (motor imbalance, bearing wear, pump cavitation). The X/Y dual-axis sensing captures both lateral and radial vibration components in a single part, reducing PCB area versus two single-axis sensors. The ±10 g envelope accommodates machine-startup transients without saturating. Its 2.7 V to 3.6 V supply range interfaces directly with 3.3 V MCUs and ADCs without level shifters. According to the NXP datasheet, factory-trimmed sensitivity of 120 mV/g enables direct voltage-to-engineering-unit conversion in software, with consistent gain across the operating-temperature range thanks to on-chip temperature compensation.
Recommended
Consumer Electronics Orientation Detection
For handheld consumer devices (remote controls, gaming peripherals, point-of-sale terminals), the MMA6231Q provides accurate X/Y orientation detection in a small 6 × 6 mm QFN package. Its low supply current (single-digit mA typical) preserves battery life, while the internal self-test verifies sensor integrity on demand. The factory-trimmed offset means no in-line calibration step during final assembly, lowering production cost. Compared with discrete tilt switches, the MMA6231Q enables proportional angle measurement rather than binary detection, supporting richer UI features like tilt-to-scroll, gaming gravity controls and auto-rotate response. The lead-free / RoHS-compliant assembly matches consumer electronics manufacturing requirements.
Recommended
Appliance Motion Detection (Washers, Dryers, Refrigerators)
The MMA6231Q's ±10 g range covers vibration signatures generated by unbalanced laundry loads, compressor startups and door-slam events in major appliances. Its 300 Hz bandwidth captures the spectral content relevant to load-balancing algorithms in washing machines and to anti-vibration suspension control in dryers. The wide 2.7 V to 3.6 V supply range directly accepts 3.3 V rails already common in appliance control boards. On-chip temperature compensation maintains sensitivity across the -20 °C to +85 °C operating range, matching typical appliance ambient conditions. The internal self-test feature supports end-of-line functional verification in high-volume manufacturing, where mechanical actuation of a discrete test jig would be uneconomic.
Recommended
Automotive Security and Tamper Detection
The MMA6231Q's ±10 g full-scale range and dual-axis X/Y sensing enable tilt/tow-away detection and intrusion-vibration sensing in vehicle security systems. The internal electronic self-test ensures the sensor remains functional across the part's operating life without mechanical actuation. The 16-pin QFN-EP (6 × 6 mm) footprint fits the compact module PCBs typical of aftermarket alarm units. Designers can read the analog outputs directly with a low-cost MCU ADC, implementing wake-on-motion via software thresholds. For automotive-grade applications, NXP recommends transitioning to the MMA6800 family (AEC-Q100, -40 °C to +105 °C) which shares the same QFN-16 footprint, enabling a pin-compatible upgrade without PCB rework.
Recommended
General Dual-Axis Motion and Position Sensing
The MMA6231Q serves as a general-purpose X/Y motion sensor for hobbyist boards, instrumentation front-ends and prototyping platforms where a simple analog output is preferred. The 3.3 V supply and analog outputs pair naturally with Arduino-class MCU ADCs; a single line of code converts millivolts to g. The factory-trimmed zero-g offset eliminates one of the most common sources of error in first-time MEMS users, making the part appropriate for educational and rapid-prototyping environments. Designers gain access to a documented sensing element from NXP's automotive-grade MEMS portfolio without committing to digital-interface firmware. For embedded designs requiring digital readout, NXP's MMA6800 family provides a pin-compatible smart-sensor upgrade path.
Recommended
Recommended Products Summary
Engineering reference data for MMA6231Q — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | MMA6233Q | MMA6801KW | MMA6821KW |
|---|---|---|---|---|
| Brand | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors |
| Package | 16-pin QFN-EP (6 x 6 mm) | 16-pin QFN-EP (6 x 6 mm) - same footprint | 16-pin QFN (6 x 6 mm) - same footprint | 16-pin QFN (6 x 6 mm) - same footprint |
| Sensitivity | 120 mV/g typical (111 to 129 mV/g) | ≈48 mV/g (factory-trimmed for ±25 g) | Digital output (LSB/g) - SPI/CAN | Digital output (LSB/g) - SPI/CAN |
| Output Type | Analog (X_OUT, Y_OUT) | Analog (X_OUT, Y_OUT) | Digital (SPI/CAN) | Digital (SPI/CAN) |
| Operating Temperature | -20 °C to +85 °C | -20 °C to +85 °C | -40 °C to +105 °C (automotive) | -40 °C to +105 °C (automotive) |
| Self-Test | Yes (electronic ST) | Yes (electronic ST) | Yes (electronic ST) | Yes (electronic ST) |
| AEC-Q100 Automotive | Not qualified | Not qualified | Qualified (AEC-Q100) | Qualified (AEC-Q100) |
Key Differentiators
- Highest absolute sensitivity in same-package NXP MMA6200 family (vs MMA6233Q)
- Pin-compatible footprint with NXP MMA6800 smart-sensor family (vs MMA6801KW)
- Wider industrial temperature coverage vs automotive-grade siblings (vs MMA6821KW)
Design Notes
Place a 0.1 µF X7R ceramic decoupling capacitor as close as practical between VDD (pin 1) and GND (pin 2), with short traces to minimize inductive ringing on the supply rail. The MMA6231Q contains both an analog ASIC and a MEMS transducer; an LC or RC filter on VDD is optional but recommended for high-noise environments (e.g., motor controller boards), where a 10 Ω ferrite + 10 µF bulk cap can reduce conducted noise coupling into the X/Y outputs.
Solder the exposed thermal pad (EP) to a continuous PCB ground pour to provide mechanical stability and a low-impedance ground reference. Orient the package so that the X and Y sensing axes align with your reference frame; the printed axis indicators (visible from the top-view pin-1 marker) are documented in the NXP datasheet mechanical drawing. Avoid routing high-current switching traces (FET gate drives, motor phases) directly under the QFN body, since stray switching noise can couple into the sensitive MEMS sense cell.
Do not assume the NC pins are electrically inert - on some MMA6200-series variants, NC pins are factory test points and should be left floating on the PCB (no connection to GND or VDD). Failing to leave NC pins floating can load the internal ASIC and degrade the zero-g offset calibration. According to the NXP datasheet, do not tie NC pins together. Always reference the specific variant's mechanical drawing to confirm NC pin assignments before laying out the PCB.
Estimated: assuming a 10-bit ADC with 3.3 V full-scale, the MMA6231Q's 120 mV/g sensitivity corresponds to 37 LSB/g, providing roughly 4.6 mg/LSB resolution - sufficient for tilt and moderate-vibration measurements but marginal for sub-mg seismic applications. For higher resolution, oversample and average (e.g., 16× to 64× averaging) or move to a 12-bit or 16-bit ADC. Add a small RC (1 kΩ + 10 nF) at the ADC input if sensor trace length exceeds 25 mm to limit coupled noise.
Compliance Information
RoHS and lead-free per DigiKey catalog data and NXP product page. AEC-Q100 not qualified - migrate to MMA6800 family for automotive. REACH and conflict-minerals statements are documented on NXP's corporate compliance page.
