The ADXL212 series 2-axis PWM Output Accelerometer with high precision, low power, signal conditioned and duty cycle modulated outputs, all on a single monolithic IC. The ADXL212 measures both dynamic acceleration (such as vibration) and static acceleration (such as gravity). The outputs are digital signals whose duty cycles (ratio of pulse width to period) are proportional to acceleration (12.5%/g) in each of the two sensitive axes. The duty cycle outputs can be directly measured by a microcontroller without an analog-to-digital converter (ADC) or glue logic. The output period is adjustable from 0.5 to 10ms via a single resistor (RSET). The typical noise floor is 500µg/√Hz, allowing signals below 5mg (0.3° of inclination) to be resolved in tilt sensing applications using narrow bandwidths (<60Hz). The user selects the bandwidth of the accelerometer using Capacitors CX and CY at the XFILT and YFILT pins. Bandwidths of 0.5to 500Hz can be selected to suit the application.
