Automotive-grade Z-axis shock sensing
The NXP MMA1725WR2 is a single-axis (Z) digital accelerometer from the automotive-qualified MMA series, rated for ±250g full-scale acceleration. This is a part designed for crash detection, impact monitoring, or high-G event logging in vehicle systems where AEC-Q100 grade qualification and PPAP documentation are non-negotiable.
Supply, interface, and filter flexibility
Supply voltage spans 4V to 20V, so it runs directly off an unregulated 12V automotive battery rail without an intermediate regulator. The output is available as PCM (a serial audio-style stream) or SPI — SPI is the standard for microcontroller integration, while PCM can feed a codec or DSP directly without a separate serial interface. A selectable low-pass filter lets the designer tailor the measurement bandwidth to the mechanical vibration profile of the target — useful for separating crash pulses from road noise or engine harmonics without external filtering. Sensitivity is 2.048 LSB/g, which gives a digital count of about 512 at 250g — enough resolution to distinguish a 0.5g change in a 250g event without a high-resolution external ADC.
Package and board integration
Housed in a 16-QFN with exposed pad (6x6 mm footprint), the MMA1725WR2 requires the thermal paddle to be soldered to a PCB ground plane — this provides both the thermal path for self-heating and the mechanical anchor for the MEMS sensing element. Surface-mount only; no through-hole option.