ADIS16362

Rev. 0 | Page 12 of 20

CALIBRATION

Manual Bias Calibration

The bias offset registers in Table 15 and Table 16 provide a

manual adjustment function for the output of each sensor. For

example, if XGYRO_OFF = 0x1FF6 (DIN = 0x9B1F, 0x9AF6),

the XGYRO_OUT offset shifts by −10 LSBs, or −0.125°/sec.

Table 15. XGYRO_OFF, YGYRO_OFF, ZGYRO_OFF

Bit Descriptions

Bit

Description (Default = 0x0000)

[15:13]

Not used.

[12:0]

Data bits. Twos complement, 0.0125°/sec per LSB.

Typical adjustment range = ±50°/sec.

Table 16. XACCL_OFF, YACCL_OFF, ZACCL_OFF

Bit Descriptions

Bit

Description (Default = 0x0000)

[15:12]

Not used.

[11:0]

Data bits. Twos complement, 0.333 mg/LSB.

Typical adjustment range = ±0.3 g.

Gyroscope Automatic Bias Null Calibration

Set GLOB_CMD[0] = 1 (DIN = 0xBE01) to execute the auto-

matic bias null calibration function. This function measures all

three gyroscope output registers and then loads each gyroscope

offset register with the opposite value to provide a quick bias

calibration. All sensor data is then reset to 0, and the flash

memory is updated automatically within 50 ms (see Table 17).

Gyroscope Precision Automatic Bias Null Calibration

Set GLOB_CMD[4] = 1 (DIN = 0xBE10) to execute the precision

automatic bias null calibration function. This function takes the

sensor offline for 30 sec while it collects a set of data and calculates

more accurate bias correction factors for each gyroscope. After

this function is executed, the newly calculated correction factor

is loaded into the gyroscope offset registers, all sensor data is

reset to 0, and the flash memory is updated automatically within

50 ms (see Table 17).

Restoring Factory Calibration

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

calibration restore function. This function resets each user cali-

bration register to 0x0000 (see Table 15 and Table 16), resets all

sensor data to 0, and automatically updates the flash memory

within 50 ms (see Table 17).

Linear Acceleration Bias Compensation (Gyroscope)

Set MSC_CTRL[7] = 1 (DIN = 0xB486) to enable correction for

low frequency acceleration influences on gyroscope bias. Note

that the DIN sequence also preserves the factory default condi-

tion for the data ready function (see Table 22).

OPERATIONAL CONTROL

Global Commands

The GLOB_CMD register provides trigger bits for several use-

ful functions. Setting the assigned bit to 1 starts each operation,

which returns the bit to 0 after completion. For example, set

GLOB_CMD[7] = 1 (DIN = 0xBE80) to execute a software

reset, which stops the sensor operation and runs the device

through its start-up sequence. This sequence includes loading

the control registers with their respective flash memory locations

prior to producing new data. Reading the GLOB_CMD register

(DIN = 0x3E00) starts the burst read sequence.

Table 17. GLOB_CMD Bit Descriptions

Bit

Description

[15:8]

Not used

[7]

Software reset command

[6:5]

Not used

[4]

Precision autonull command

[3]

Flash update command

[2]

Auxiliary DAC data latch

[1]

Factory calibration restore command

[0]

Autonull command