The data sheet for the ADXL193 describes the self test function: "Activating self-test causes a step function force to be applied to the sensor, while the capacitive coupling term is canceled. The ADXL193 has improved self-test functionality, including excellent transient response and high speed switching capability. Arbitrary force waveforms can be applied to the sensor by modulating the self-test input, such as test signals to measure the system frequency response, or even crash signals to verify algorithms within the limits of the self-test swing." Am I understanding this properly that a known input signal can be applied to the ST pin and the accelerometer's actual response that would be proportional to a real-world acceleration will be output? The existing circuit has this pin connected to a MPU port that is not used. I would like to inquiry our EEs to consider using the ST if operates in the mode I am interpreting. We are using the AD 22282 version. Thanks!
In self-test mode, the part does not respond to external acceleration. You could use this mode to obtain the sensing element's frequency response; that is essentially what the paragraph tries to say. Hope…
Thank you very much for the reply and assistance. Best regards, Brian