Analog Devices AN625 Application Notes

9106

www.analog.com

range of

ADXRS150 a

5A

4A

7B

7C

1B

3F

1E

3A

7D 4F 5F 1C

7E 6G 2G 1D

ADXRS150ABG

Alternatively, a resistor could be placed between the

ADXRS150, the modi ed dynamic range is roughly

where

is the external resistor between CMID and

is the external resistor between CMID and

has a

value that varies

this technique will have to adjust the external resistor

value somewhat for each part in order to arrive at an

sensitivity value.

A low tempco resistor is recommended because the

the scale factor of a given part by a factor of approxi-

that since the internal resistor (R

formance of the gyro (by as much as 2°/s over the

–40°C to +85°C range).

RANGE R R

NEW EXT EXT

= ¥ + +

( )

( )

( )

75 1 2 2 18

SCALE R R

NEW EXT EXT

= + +

( )

[ ]

¥(1 ) / 12.58 2 9

–2

–

tered trademarks are the property of their respective companies.

Table I. Scale Factor for Various Values of R

ADXRS150

ADXRS300

the gyro’s resonator must be attenuated. This is done by

factor. Table II shows some experimental results using

this technique with the ADXRS150.

Table II. Scale Factor for Various Values of V

V

will cause a change in the scale factor. Since even small

variances in CP5 voltage result in large changes in scale

factor, the user must calibrate both the null and sensitiv-

and

theoretically be achieved. Such extreme measures must

to ensure suitable operation in the application.

that the user requires. In general, adding external pas-

requires that the user recalibrate

the null and sensitivity.