Design of micro accelerometer (стр. 3 из 3)

and for tilt motion:

Discussion

Specifications of accelerometer made using MOSIS process were estimated. Some of features are presented in Table 3. Also, corresponding specifications of ADXL50 are presented for comparison.

As we can see some of characteristics, as device size, dynamic range and bandwidth, have similar range.

These two accelerometers use different readout principles. The ADXL50 uses a capacitive measurement method. Whereas accelerometer designed in this work uses piezoresistors to generate output signal. But still comparable characteristic can be obtained. Moreover, some of parameters of accelerometer made by MOSIS process are better. For example, it has higher sensitivity and lower noise.

In this work to find some parameters sometimes very rough estimations were applied. In order to find their values more precisely more accurate techniques are required. But made analysis is suitable to see performance of a device which can be achieved if we use MOSIS process to fabricate this device.

Specification	Value	ADXL50	Unit
Device size, approx.	1x1x-	9.4x9.4x24.2	mm
Seismic mass	3.6	-
Dynamic range	-100~100	-50~50	g
	-980~980	-490~490
Sensitivity
Resolution		-
	0.66	g
Noise
			g
Frequency range	Up to 15	Up to 10	kHz

Table 3. Accelerometer’s specifications and comparison with ADXL50