ADIS16407/PCBZ Analog Devices Inc, ADIS16407/PCBZ Datasheet - Page 19
![no-image](/images/manufacturer_photos/0/0/57/analog_devices_inc_sml.jpg)
ADIS16407/PCBZ
Manufacturer Part Number
ADIS16407/PCBZ
Description
ADIS16407/PCB EVAL. BD.
Manufacturer
Analog Devices Inc
Series
iMEMS®, iSensor™r
Specifications of ADIS16407/PCBZ
Sensor Type
Accelerometer, Gyroscope, Magnetometer, 3 Axis
Sensing Range
±18g, ±75°/sec, ±150°/sec, ±300°/sec, ±2.5gauss
Interface
SPI Serial
Sensitivity
3.33mg/LSB, 0.0125 ~ 0.05°/sec/LSB, 0.5mgauss/LSB
Voltage - Supply
4.75 V ~ 5.25 V
Embedded
No
Utilized Ic / Part
ADIS16407
Kit Application Type
Sensing - Motion / Vibration / Shock
Application Sub Type
Shock Sensor
Silicon Manufacturer
Analog Devices
Silicon Core Number
ADIS16407
Kit Contents
Board, Manual
Lead Free Status / Rohs Status
Lead free / RoHS Compliant
CALIBRATION
The mechanical structure and assembly process of the ADIS16407
provide excellent position and alignment stability for each sensor,
even after subjected to temperature cycles, shock, vibration, and
other environmental conditions. The factory calibration includes a
dynamic characterization of each gyroscope and accelerometer over
temperature and generates sensor specific correction formulas.
Table 48 provides a list of registers that can help optimize system
performance after installation. Figure 20 illustrates the summing
function for the offset correction register of each sensor.
Table 48. Registers for User Calibration
Register
XGYRO_OFF
YGYRO_OFF
ZGYRO_OFF
XACCL_OFF
YACCL_OFF
ZACCL_OFF
XMAGN_HIC
YMAGN_HIC
ZMAGN_HIC
XMAGN_SIC
YMAGN_SIC
ZMAGN_SIC
MSC_CTRL
GLOB_CMD
GYROSCOPES
The XGYRO_OFF (Table 49), YGYRO_ OFF (Table 50), and
ZGYRO_ OFF (Table 51) registers provide user-programmable
bias adjustment function for the x-, y-, and z-axis gyroscopes,
respectively. Figure 20 illustrates that they contain bias correction
factors that adjust to the sensor data immediately before it loads
into the output register.
Gyroscope Bias Error Estimation
Any system level calibration function must start with an estimate
of the bias errors, which typically comes from a sample of gyro-
scope output data, when the device is not in motion. The sample
size of data depends on the accuracy goals. Figure 7 provides a
trade-off relationship between averaging time and the expected
accuracy of a bias measurement. Vibration, thermal gradients,
and power supply instability can influence the accuracy of this
process.
X-AXIS
MEMS
GYRO
Figure 20. User Calibration, XGYRO_OFF Example
Address
0x1E
0x20
0x22
0x24
0x26
0x28
0x2A
0x2C
0x2E
0x30
0x32
0x34
0x38
0x42
ADC
CALIBRATION
FILTERING
FACTORY
Gyroscope bias, x-axis
Gyroscope bias, y-axis
Gyroscope bias, z-axis
Accelerometer bias, x-axis
Accelerometer bias, y-axis
Accelerometer bias, z-axis
Soft iron correction, x-axis
Soft iron correction, y-axis
Soft iron correction, z-axis
Miscellaneous calibration
Automatic calibration
Description
Hard iron correction, x-axis
Hard iron correction, y-axis
Hard iron correction, z-axis
AND
XGYRO_OFF
XGYRO_OUT
Rev. B | Page 19 of 24
Table 49. XGYRO_OFF (Base Address = 0x1E), Read/Write
Bits
[15:14]
[13:0]
Table 50. YGYRO_OFF (Base Address = 0x20), Read/Write
Bits
[15:14]
[13:0]
Table 51. ZGYRO_OFF (Base Address = 0x22), Read/Write
Bits
[15:14]
[13:0]
Gyroscope Bias Correction Factors
When the bias estimate is complete, multiply the estimate by −1
to change its polarity, convert it into digital format for the offset
correction registers (Table 49), and write the correction factors
to the correction registers. For example, lower the x-axis bias by
10 LSB (0.125°/sec) by setting XGYRO_OFF = 0x1FF6 (DIN =
0x9F1F, 0x9EF6).
Single Command Bias Correction
GLOB_CMD[0] (Table 32) loads the xGYRO_OFF registers
with the values that are the opposite of the values that are in
xGYRO_OUT, at the time of initiation. Use this command,
together with the decimation filter (SMPL_PRD[12:8], Table 46),
to automatically average the gyroscope data and improve the
accuracy of this function, as follows:
1.
2.
3.
4.
Set SENS_AVG[10:8] = 001 (DIN = 0xBD01) to optimize
the xGYRO_OUT sensitivity to 0.0125°/sec/LSB.
Set SMPL_PRD[12:8] = 0x10 (DIN = 0xBB10) to set the
decimation rate to 65,536 (2
time of 80 seconds (65,536 ÷ 819.2 SPS).
Wait for 80 seconds while keeping the device motionless.
Set GLOB_CMD[0] = 1 (DIN = 0xC201) and wait for the
time it takes to perform the flash memory backup (~75 ms).
Description (Default = 0x0000)
Not used
X-axis, gyroscope offset correction factor,
twos complement, 0.0125°/sec per LSB
Description (Default = 0x0000)
Not used
Y-axis, gyroscope offset correction factor,
twos complement, 0.0125°/sec per LSB
Description (Default = 0x0000)
Not used
Z-axis, gyroscope offset correction factor,
twos complement, 0.0125°/sec per LSB
16
), which provides an averaging
ADIS16407