Data Sheet

ADIS16445

Rev. F | Page 19 of 22

Accelerometer Bias Correction Factors

When the bias estimate is complete, multiply the estimate by

−1 to change its polarity, convert it to the digital format for the

offset correction registers (see Table 33, Table 34 or Table 35),

and write the correction factors to the correction registers. For

example, lower the x-axis bias by 12 LSB (3 mg) by setting

XACCL_OFF = 0xFFF4 (DIN = 0xA1FF, 0xA0F4).

Point of Percussion Alignment

Set MSC_CTRL[6] = 1 (DIN = 0xB446) to enable this feature

and maintain the factory default settings for DIO1. This feature

performs a point of percussion translation to the point identified

in Figure 21. See Table 24 for more information on MSC_CTRL.

ORIGIN ALIGNMENT

REFERENCE POINT

SEE MSC_CTRL[6].

Figure 21. Point of Percussion Physical Reference

FLASH UPDATES

When using the user calibration registers to optimize system

level accuracy, set GLOB_CMD[3] = 1 (DIN = 0xBE04) to save

these settings in nonvolatile flash memory. Be sure to consider

the endurance rating of the flash memory when determining how

often to update the user correction factors in the flash memory.

RESTORING FACTORY CALIBRATION

Set GLOB_CMD[1] = 1 (DIN = 0xBE02) to execute the factory

calibration restore function, which resets the gyroscope and accel-

erometer offset registers to 0x0000 and all sensor data to 0. Then, it

automatically updates the flash memory and restarts sampling and

processing data. See Table 19 for information on GLOB_CMD.