Q
1. ADXL203 Accelerometer itself is marked 33878203xlI382, Is the accelerometer
supposed to have a zero G bias of 0V or 2.5V?
2. At zero G upon measurement with an oscilloscope my accelerometer produces 1V
and the self test feature produces an increase in output of approximately 200mv
instead of the datasheet quoted value of 750mv. Is this correct or am I missing
something here?
3. Is there a voltage follower circuit to take the voltage down to 0 that ADI
have recommended?
A
1. The 0g output of ADXL203 is Vs/2, so if the Vs=5V, the 0g output is 2.5V.
2. If you power ADXL203 with 5V supply, ADXL203 is stable on table or say no
external acceleration influence, the tested axis is in 0g field, this is
incorrect.
But lower supply, external acceleration influence can also cause what you saw.
3. Attached is a CN for ADXL203. You can also use the subtractor circuit to
reject the common-mode voltage. Attached paper could be used as a reference.