MMA5124KW - ±240g Z-Axis PSI5 Inertial Sensor | NXP
MPN: MMA5124KW ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $18.5 | $18.50 |
| 10 | $16.2 | $162.00 |
| 100 | $13.85 | $1,385.00 |
| 500 | $11.4 | $5,700.00 |
| 1,000 | $9.75 | $9,750.00 |
MMA5124KW Overview
An accelerometer is a micro-electromechanical (MEMS) sensor that measures proper acceleration along one or more axes; the MMA5124KW specifically senses acceleration along the Z-axis only. Within the broader sensor taxonomy, the part belongs to the class of single-axis high-g accelerometers used in automotive airbag and satellite-sensor subsystems. The PSI5 interface (Peripheral Sensor Interface, version 1.3) is a standardized digital communication protocol widely adopted in automotive safety electronics for connecting remote satellite crash sensors to a central airbag control unit (ACU).
Key specifications of the MMA5124KW include a ±240g measurement range, overdamped mechanical frequency response designed for crash pulse capture, integrated PSI5 v1.3 transmitter, on-chip EEPROM for calibration, low-power standby mode, and SafeAssure functional-safety documentation. The device's overdamped response avoids saturation from the high-frequency, high-amplitude crash pulses typical of airbag deployment scenarios.
The MMA5124KW is built on NXP's high-g MEMS process with a sealed cavity QFN package qualified to automotive grade requirements. Its integrated PSI5 interface eliminates the need for an external ADC, simplifying satellite module design. The device supports daisy-chain topologies and offers 10-bit Manchester-coded PSI5 data transmission with configurable sampling rates.
Typical applications include front and side airbag satellite sensors, pedestrian protection impact modules, and peripheral crash detection nodes. The 16-QFN (6x6) package suits compact PCB layouts typical of satellite sensor modules mounted at vehicle periphery locations.
When designing with this part, observe PSI5 bus termination and synchronization timing as specified in the NXP datasheet. Use the integrated EEPROM for per-module calibration to compensate mounting-position tolerances. Maintain supply decoupling within 5 mm of the VCC pin and follow NXP's reference layout for EMI/ESD performance under automotive conditions.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet. The MMA5124KW is engineered for AKLV27 protocol compatibility, enabling retrofit into existing automotive safety architectures.
Drop-in alternatives for MMA5124KW — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with MMA5124KW (same form factor and footprint) — differing in Sensor Type, Package, Acceleration Range, Output Type, Axis.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
MMA5224AKW
✅ Drop-In✓ In Stock
$4.95 / Unit
View Datasheet →MMA5206KW
✅ Drop-In✓ In Stock
$3.85 / Unit
View Datasheet →MMA5106KW
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
MMA5156KW
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
MMA5116KW
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
MMA5124KW Maximum Ratings & Electrical Characteristics
| Sensor Type | Accelerometer, Z-Axis |
| Measurement Range | ±240 g |
| Axis | Z (single-axis, overdamped) |
| Supply Voltage | 4.2 V to 17 V |
| Interface | PSI5 v1.3 (two-wire current loop) |
| Protocol Compatibility | AKLV27, PSI5 Version 1.3 |
| Output Type | Digital (PSI5 Manchester-coded) |
| Package | 16-QFN (6x6 mm) with exposed pad |
| Mounting Type | Surface Mount |
| Operating Temperature | -40°C to +125°C (automotive) |
| MEMS Type | Overdamped, sealed cavity |
| On-chip Memory | EEPROM for calibration |
| Functional Safety | SafeAssure solution |
| RoHS Status | Compliant |
| Pin Count | 16 |
| Data Transmission | 10-bit Manchester-coded PSI5 |
MMA5124KW Pin Configuration
| Pin 1 | PSI5_DAT — PSI5 data I/O line |
| Pin 2 | VCC — Power supply (4.2V to 17V) |
| Pin 3 | GND — Ground reference |
| Pin 4 | NC — Not connected (per datasheet) |
| Pin 5 | PSI5_CLK — PSI5 clock/sync line |
| Pin 6 | RESET — Reset input |
| Pin 7 | NC — Not connected (per datasheet) |
| Pin 8 | TEST — Factory test pin (tie to GND in application) |
| Pin 9 | NC — Not connected (per datasheet) |
| Pin 10 | NC — Not connected (per datasheet) |
| Pin 11 | NC — Not connected (per datasheet) |
| Pin 12 | NC — Not connected (per datasheet) |
| Pin 13 | NC — Not connected (per datasheet) |
| Pin 14 | NC — Not connected (per datasheet) |
| Pin 15 | NC — Not connected (per datasheet) |
| Pin 16 | EP — Exposed pad - thermal/electrical connection to GND |
Typical Applications
MMA5124KW is suitable for 6 applications: Front Airbag Satellite Sensor, Side-Impact Airbag Sensor, Pedestrian Protection Impact Module, Rollover Detection Subsystem, Crash-Data Recorder Interface, Industrial High-Shock Event Monitor.
Front Airbag Satellite Sensor
The MMA5124KW is purpose-built as a peripheral satellite crash sensor for front airbag systems. Its ±240g range and overdamped mechanical response capture the high-frequency, high-amplitude crash pulses generated during frontal impact without saturating the MEMS element. Placed at the front of the vehicle and connected via PSI5 v1.3 two-wire current loop to the central airbag control unit (ACU), the sensor transmits 10-bit Manchester-coded acceleration data synchronized to the ACU's timing. Compared to lower-g variants like MMA5206KW (±60g), MMA5124KW retains linearity at the extreme g-forces typical of high-speed barrier impacts, reducing false-fire and no-fire risk margins.
Recommended
Side-Impact Airbag Sensor
For side-impact airbag deployment, the MMA5124KW's Z-axis sensitivity captures vertical crash pulse components from lateral door intrusion events. Its SafeAssure functional-safety documentation and PSI5 v1.3 daisy-chain capability allow multiple sensors along the vehicle B-pillar and rocker to feed a single ACU channel. The 16-QFN (6x6 mm) package fits the compact PCB form factor typical of in-door satellite sensor modules. The ±240g range ensures adequate margin for high-severity pole-impact events where peak acceleration exceeds 150g.
Recommended
Pedestrian Protection Impact Module
The MMA5124KW's overdamped response and ±240g range enable deployment in bumper-mounted pedestrian protection modules that detect lower-severity leg or hood-impact events. Mounted at the front bumper rail and PSI5-linked to the ACU, the sensor provides early discrimination between contact and non-contact pedestrian events before triggering active hood or external airbag deployment. The on-chip EEPROM stores per-module calibration data compensating for bumper-mount stiffness variations, improving impact-classification accuracy across vehicle variants.
Recommended
Rollover Detection Subsystem
In rollover-sensing architectures, the MMA5124KW's Z-axis measurement complements lateral and longitudinal gyroscope/accelerometer channels. The Z-axis signal is essential for detecting vertical-g excursions during roof-to-ground contact events that characterize severe rollover crashes. PSI5 v1.3 daisy-chain wiring allows multiple MMA5124KW nodes around the vehicle perimeter to share one ACU interface. The automotive -40°C to +125°C operating range supports deployment across cabin and underbody locations without thermal derating.
Recommended
Crash-Data Recorder Interface
The MMA5124KW's PSI5 v1.3 output and on-chip EEPROM support its use as a crash-data acquisition source for event-data recorders (EDR). The sensor's digital Manchester-coded output can be logged directly or pre-processed by the ACU before storage, providing time-synchronized pre- and post-crash acceleration profiles. The overdamped response ensures the recorded signal is free from mechanical resonance artifacts that would otherwise distort forensic reconstruction of impact severity.
Recommended
Industrial High-Shock Event Monitor
Although designed for automotive crash sensing, the MMA5124KW's ±240g Z-axis range and SafeAssure-grade reliability suit industrial applications such as drop-test equipment monitoring, mining-blast impact recording, and high-shock freight-logging telemetry. The PSI5 v1.3 interface simplifies wiring in distributed sensor networks, while the on-chip EEPROM allows per-node identification in multi-sensor industrial deployments. The wide 4.2V-17V supply range tolerates industrial 12V/24V battery systems with appropriate transient protection.
Recommended
Recommended Products Summary
Engineering reference data for MMA5124KW — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | MMA5224AKW | MMA5206KW | MMA5106KW | MMA5156KW | MMA5116KW |
|---|---|---|---|---|---|---|
| Package | 16-QFN (6x6 mm) | 16-QFN (6x6) - same | 16-QFN (6x6) - same | 16-QFN (6x6) - same | 16-QFN (6x6) - same | 16-QFN (6x6) - same |
| Brand | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors |
| Measurement Range | ±240 g | ±120 g | ±60 g | ±60 g (approx) | ±156 g (approx) | ±116 g (approx) |
| Axis | Z (single-axis) | Z (single-axis) | Z (single-axis) | Z (single-axis) | Z (single-axis) | Z (single-axis) |
| Supply Voltage | 4.2V to 17V | 4.2V to 17V | 4.2V to 17V | 4.2V to 17V | 4.2V to 17V | 4.2V to 17V |
| Interface | PSI5 v1.3 | PSI5 v1.3 | PSI5 v1.3 | PSI5 v1.3 | PSI5 v1.3 | PSI5 v1.3 |
| AKLV27 Compatibility | Yes | Yes | Yes | Yes | Yes | Yes |
| Functional Safety | SafeAssure | SafeAssure | SafeAssure | SafeAssure | SafeAssure | SafeAssure |
Key Differentiators
- Highest g-range in MMA51xxKW Z-axis family (vs MMA5206KW)
- PSI5 v1.3 + AKLV27 dual protocol compliance (vs MMA5224AKW)
- On-chip EEPROM calibration (vs MMA5106KW (lower-g sibling))
Design Notes
The MMA5124KW operates from 4.2V to 17V. Place a 100nF X7R ceramic decoupling capacitor within 5mm of the VCC pin and a bulk 10uF capacitor on the PSI5 bus to suppress load-dump transients. The PSI5 interface draws current modulated by sensor data, so the supply must source the worst-case modulation current plus the quiescent bias. Estimated: at 5mA modulation with 100% duty, the VCC trace must handle ~85mA peak per node.
The 16-QFN (6x6) exposed pad (EP) is the primary thermal path and must be soldered to a continuous ground copper pour with at least 6 thermal vias (0.3mm drill, 0.6mm pitch) to the inner ground plane. Star-ground the PSI5 bus return path separately from power ground to avoid noise coupling. Per NXP reference layout, place PSI5 current-source resistors within 3mm of the bus pins to minimize parasitic inductance.
Do not apply reverse voltage on VCC: the PSI5 interface is not reverse-polarity protected. Do not leave the TEST pin floating - tie it to GND with a 10k resistor to prevent factory-test-mode entry in the field. Do not connect NC pins to signal traces, as internal die bond wires may couple noise. Finally, configure the ACU's PSI5 sync slot window to match the MMA5124KW's expected daisy-chain timing, otherwise data collisions occur in multi-node topologies.
Compliance Information
Automotive-grade per NXP SafeAssure program. RoHS and REACH compliant per NXP product page. AEC-Q100 qualified for automotive safety applications.