AD ADIS16385BMLZ

FEATURES
Triaxis digital gyroscope with digital range scaling
±75°/sec, ±150°/sec, ±300°/sec settings
Orthogonal alignment: <0.05°
In-run bias stability: 6°/hour (yaw), 25°/hour (pitch/roll)
Triaxis digital accelerometer: ±5 g
Autonomous operation and data collection
No external configuration commands required
Startup time: 180 ms
Sleep mode recovery: 4 ms
Factory-calibrated sensitivity, bias, and axial alignment
Calibration temperature range: −40°C to +85°C
Single serial peripheral interface, SPI-compatible
Wide bandwidth: 330 Hz
Embedded temperature sensor
Programmable operation and control
Automatic and manual bias correction controls
Digital filters: Bartlett FIR, average/decimation
Digital I/O: data-ready, alarm indicator, general-purpose
Alarms for condition monitoring
Sleep mode for power management
DAC output voltage
Enable external sample clock input: up to 1.2 kHz
Single-supply operation: 4.85 V to 5.15 V
2000 g shock survivability
Operating temperature range: −40°C to +105°C
APPLICATIONS
Platform stabilization and control
Navigation
Robotics
FUNCTIONAL BLOCK DIAGRAM
AUX_ADC
AUX_DAC
TEMPERATURE
SENSOR
TRI-AXIS MEMS
ANGULAR RATE
SENSOR
CS
SIGNAL
CONDITIONING
AND
CONVERSION
CALIBRATION
AND
DIGITAL
PROCESSING
OUTPUT
REGISTERS
AND SPI
INTERFACE
SCLK
DIN
DOUT
TRI-AXIS MEMS
ACCELERATION
SENSOR
ALARMS
SELF-TEST
DIGITAL
CONTROL
POWER
MANAGEMENT
VCC
GND
ADIS16360/
ADIS16385
ADIS16365
RST DIO1 DIO2 DIO3 DIO4/CLKIN
07570-001
Preliminary Technical Data
Six Degrees of Freedom Inertial Sensor
ADIS16385
Figure 1.
GENERAL DESCRIPTION
The ADIS16385 iSensor® devices are complete inertial systems
that include a triaxis gyroscope and triaxis accelerometer. Each
sensor in the ADIS16385 combines industry-leading iMEMS®
technology with signal conditioning that optimizes dynamic
performance. The factory calibration characterizes each sensor
for sensitivity, bias, alignment, and linear acceleration (gyro bias).
As a result, each sensor has its own dynamic compensation formulas
that provide accurate sensor measurements. The yaw-axis gyroscope offers a 4× improvement in noise and in-run bias stability
for applications that have greater requirements on one axis.
The ADIS16385 provide a simple, cost-effective method for
integrating accurate, multiaxis inertial sensing into industrial
systems, especially when compared with the complexity and
investment associated with discrete designs. All necessary motion
testing and calibration are part of the production process at the
factory, greatly reducing system integration time. Tight orthogonal
alignment simplifies inertial frame alignment in navigation systems.
The SPI and register structure provide a simple interface for
data collection and configuration control.
The ADIS16385 has a compatible pinout for systems that currently
use ADIS1635x, ADIS1636x, and ADIS1640x IMU products.
It comes in a module that is approximately 36 mm × 47 mm ×
39 mm and has a standard connector interface.
Rev. PrA
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700
www.analog.com
Fax: 781.461.3113
©2010 Analog Devices, Inc. All rights reserved.
ADIS16385
Preliminary Technical Data
TABLE OF CONTENTS
Features .............................................................................................. 1
Power Management ................................................................... 12
Applications ....................................................................................... 1
Product Identification................................................................ 12
Functional Block Diagram .............................................................. 1
Memory Management ............................................................... 12
General Description ......................................................................... 1
Self-Test Function ...................................................................... 13
Specifications..................................................................................... 3
Status ............................................................................................ 13
Timing Specifications .................................................................. 5
Input/Output Configuration ......................................................... 14
Timing Diagrams.......................................................................... 5
Data-Ready I/O Indicator ......................................................... 14
Absolute Maximum Ratings............................................................ 6
General-Purpose I/O ................................................................. 14
ESD Caution .................................................................................. 6
Auxiliary DAC ............................................................................ 14
Pin Configuration and Function Descriptions ............................. 7
Digital Processing Configuration ................................................. 15
Typical Performance Characteristics ............................................. 8
Calibration ....................................................................................... 16
Basic Operation................................................................................. 9
Alarms .............................................................................................. 17
Reading Sensor Data .................................................................... 9
Applications Information .............................................................. 18
Output Data Registers ................................................................ 10
Prototype Interface Board ......................................................... 18
Device Configuration ................................................................ 10
Installation Tips .......................................................................... 18
User Registers .................................................................................. 11
Outline Dimensions ....................................................................... 19
System Functions ............................................................................ 12
Ordering Guide .......................................................................... 19
Global Commands ..................................................................... 12
Rev. PrA | Page 2 of 20
Preliminary Technical Data
ADIS16385
SPECIFICATIONS
TA = 25°C, VCC = 5.0 V, angular rate = 0°/sec, dynamic range = ±300°/sec ± 1 g, unless otherwise noted.
Table 1.
Parameter
GYROSCOPES
Dynamic Range
Initial Sensitivity
Sensitivity Temperature Coefficient
Misalignment
Nonlinearity
Initial Bias Error
In-Run Bias Stability
Angular Random Walk
Bias Temperature Coefficient
Linear Acceleration Effect on Bias
Bias Voltage Sensitivity
Output Noise
Rate Noise Density
3 dB Bandwidth
Sensor Resonant Frequency
Self-Test Change in Output Response
ACCELEROMETERS
Dynamic Range
Initial Sensitivity
Sensitivity Temperature Coefficient
Misalignment
Nonlinearity
Initial Bias Error
In-Run Bias Stability
Velocity Random Walk
Bias Temperature Coefficient
Bias Voltage Sensitivity
Output Noise
Noise Density
3 dB Bandwidth
Sensor Resonant Frequency
Self-Test Change in Output Response
TEMPERATURE SENSOR
Scale Factor
Test Conditions/Comments
Dynamic range = ±300°/sec
Dynamic range = ±150°/sec
Dynamic range = ±75°/sec
−40°C ≤ TA ≤ +85°C
Reference to z-axis accelerometer
Axis-to-frame (package)
Best fit straight line
±1 σ
1σ, +25°C, Z-axis
1σ, +25°C, X-axis, Y-axis
Z-axis, 1 σ, +25°C
X-axis, Y-axis, 1 σ, +25°C
Z-axis, −40°C ≤ TA ≤ +85°C
X, Y-axes, −40°C ≤ TA ≤ +85°C
Z-axis, 1 σ (MSC_CTRL[7] = 1)
X, Y-axes, 1 σ (MSC_CTRL[7] = 1)
Z-axis, VCC = +4.85 V to +5.15V
X, Y-axes, VCC = +4.85 V to +5.15V
Z-axis, ±300°/sec range, no filtering
X, Y-axes, ±300°/sec range, no filtering
Z-axis, f = 25 Hz, ±300°/sec range
X, Y-axes, f = 25 Hz, ±300°/sec range
±300°/sec range setting
Each axis
Min
Typ
±300
0.012375
±350
0.0125
0.00625
0.003125
±40
±0.05
±0.5
±0.1
±3
<0.002
0.007
<1.0
1.9
<0.01
±0.01
<0.05
0.1
TBD
±0.3
0.25
0.8
0.013
0.044
330
14.5
±1400
±696
±5
0.2475
−40°C ≤ TA ≤ +85°C
Axis-to-axis, Δ = 90° ideal
Axis-to-frame (package)
Best fit straight line
±1 σ
1σ
1σ
−40°C ≤ TA ≤ +85°C
VCC = +4.85 V to +5.15V
No filtering
No filtering
X-axis and y-axis
0.25
±50
0.2
±0.5
0.1
±8
40
0.2
±0.3
2.5
9
0.5
330
5.5
59
Output = 0x0000 at 25°C (±5°C)
Rev. PrA | Page 3 of 20
Max
0.12625
±2449
0.2525
151
0.0678
Unit
°/sec
°/sec/LSB
°/sec/LSB
°/sec/LSB
ppm/°C
Degrees
Degrees
% of FS
°/sec
°/sec
°/sec
°/√hr
°/√hr
°/sec/°C
°/sec/°C
°/sec/g
°/sec/g
°/sec/V
°/sec/V
°/sec rms
°/sec rms
°/sec/√Hz rms
°/sec/√Hz rms
Hz
kHz
LSB
g
mg/LSB
ppm/°C
Degrees
Degrees
% of FS
mg
μg
m/sec/√hr
mg/°C
mg/V
mg rms
mg/√Hz rms
Hz
kHz
LSB
°C/LSB
ADIS16385
Parameter
ADC INPUT
Resolution
Integral Nonlinearity
Differential Nonlinearity
Offset Error
Gain Error
Input Range
Input Capacitance
DAC OUTPUT
Resolution
Relative Accuracy
Differential Nonlinearity
Offset Error
Gain Error
Output Range
Output Impedance
Output Settling Time
LOGIC INPUTS1
Input High Voltage, VIH
Input Low Voltage, VIL
Preliminary Technical Data
Test Conditions/Comments
Min
Typ
12
±2
±1
±4
±2
0
During acquisition
5 kΩ/100 pF to GND
3.3
20
12
±4
±1
±5
±0.5
101 LSB ≤ input code ≤ 4095 LSB
0
3.3
2
10
2.0
0.8
0.55
CS signal to wake up from sleep mode
CS Wake-Up Pulse Width
Logic 1 Input Current, IIH
Logic 0 Input Current, IIL
All Pins Except RST
RST Pin
Input Capacitance, CIN
DIGITAL OUTPUTS1
Output High Voltage, VOH
Output Low Voltage, VOL
FLASH MEMORY
Data Retention3
FUNCTIONAL TIMES4
Power-On Startup Time
Reset Recovery Time
Sleep Mode Recovery Time
Flash Memory Test Time
Automatic Self-Test Time
CONVERSION RATE
Clock Accuracy
Sync Input Clock
POWER SUPPLY
Power Supply Current
Max
20
VIH = 3.3 V
VIL = 0 V
ISOURCE = 1.6 mA
ISINK = 1.6 mA
Endurance2
TJ = 85°C
Time until data is available
Sleep mode
1
±10
40
1
10
60
2.4
0.4
10,000
20
TBD
TBD
TBD
TBD
TBD
1024
SMPL_PRD = 0x0001
SMPL_PRD = 0x0001
Operating voltage range, VCC
±0.2
0.85
4.85
5.0
TBD
TBD
±3
1.2
5.15
Unit
Bits
LSB
LSB
LSB
LSB
V
pF
Bits
LSB
LSB
mV
%
V
Ω
μs
V
V
V
μs
μA
μA
mA
pF
V
V
Cycles
Years
ms
ms
ms
ms
ms
SPS
%
kHz
V
mA
μA
The digital I/O signals are driven by an internal 3.3 V supply, and the inputs are 5 V tolerant.
Endurance is qualified as per JEDEC Standard 22, Method A117, and measured at −40°C, +25°C, +85°C, and +125°C.
3
The data retention lifetime equivalent is at a junction temperature (TJ) of 85°C as per JEDEC Standard 22, Method A117. Data retention lifetime decreases with junction
temperature.
4
These times do not include thermal settling and internal filter response times (330 Hz bandwidth), which may affect overall accuracy.
5
The sync input clock functions below the specified minimum value, at reduced performance levels.
2
Rev. PrA | Page 4 of 20
Preliminary Technical Data
ADIS16385
TIMING SPECIFICATIONS
TA = 25°C, VCC = 5 V, unless otherwise noted.
Table 2.
Parameter
fSCLK
tSTALL
tREADRATE
t
tDAV
tDSU
tDHD
tSCLKR, tSCLKF
tDR, tDF
tSFS
t1
tx
t2
t3
CS
1
Min1
0.01
9
40
48.8
Description
Serial clock
Stall period between data
Read rate
Chip select to clock edge
DOUT valid after SCLK edge
DIN setup time before SCLK rising edge
DIN hold time after SCLK rising edge
SCLK rise/fall times
DOUT rise/fall times
CS high after SCLK edge
Input sync positive pulse width
Input sync low time
Input sync to data ready output
Input sync period
Normal Mode
Typ
Max
2.0
Min1
0.01
1/fSCLK
Burst Read
Typ
Max
1.0
Unit
MHz
μs
μs
ns
ns
ns
ns
ns
ns
ns
μs
μs
μs
μs
48.8
100
100
24.4
48.8
24.4
48.8
5
5
12.5
12.5
5
5
5
5
100
12.5
12.5
5
5
100
600
600
833
833
Guaranteed by design and characterization, but not tested in production.
TIMING DIAGRAMS
CS
tCS
tSFS
1
2
3
4
5
6
15
16
SCLK
tDAV
MSB
DB14
DB13
tDSU
DIN
R/W
A6
DB12
DB11
A4
A3
DB10
DB2
DB1
LSB
tDHD
A5
A2
D2
D1
07570-002
DOUT
LSB
Figure 2. SPI Timing and Sequence
tREADRATE
tSTALL
07570-003
CS
SCLK
Figure 3. Stall Time and Data Rate
t3
t2
t1
tX
07570-004
SYNC
CLOCK (DIO4)
DATA
READY
Figure 4. Input Clock Timing Diagram
Rev. PrA | Page 5 of 20
ADIS16385
Preliminary Technical Data
ABSOLUTE MAXIMUM RATINGS
Table 3.
Parameter
Acceleration
Any Axis, Unpowered
Any Axis, Powered
VCC to GND
Digital Input Voltage to GND
Digital Output Voltage to GND
Analog Input to GND
Operating Temperature Range
Storage Temperature Range
Rating
2000 g
2000 g
−0.3 V to +7.0 V
−0.3 V to +5.3 V
−0.3 V to VCC + 0.3 V
−0.3 V to +3.6 V
−40°C to +105°C
−65°C to +125°C1, 2
Stresses above those listed under Absolute Maximum Ratings
may cause permanent damage to the device. This is a stress
rating only; functional operation of the device at these or any
other conditions above those indicated in the operational
section of this specification is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect
device reliability.
Table 4. Package Characteristics
Package Type
24-Lead Module (ML-24-5)
1
Extended exposure to temperatures outside the specified temperature
range of −40°C to +105°C can adversely affect the accuracy of the factory
calibration. For best accuracy, store the parts within the specified operating
range of −40°C to +105°C.
2
Although the device is capable of withstanding short-term exposure to
150°C, long-term exposure threatens internal mechanical integrity.
ESD CAUTION
Rev. PrA | Page 6 of 20
θJA
θJC
Device Weight
Preliminary Technical Data
ADIS16385
PIN CONFIGURATION AND FUNCTION DESCRIPTIONS
Z-AXIS
ADIS16385
aZ
DIO3
SCLK
DIN
DIO1
DIO2
VCC
GND
GND
DNC
DNC
AUX_ADC
DNC
TOP VIEW
(Not to Scale)
1
3
5
7
9
11
13
15
17
19
21
23
2
4
6
8
10
12
14
16
18
20
22
24
gZ
aX
aY
DNC
DNC
DNC
AUX_DAC
DNC
GND
VCC
VCC
gX
gY
PIN 23
ORIGIN ALIGNMENT REFERENCE POINT
SEE MSC_CTRL[6].
NOTES
1. ACCELERATION (aX, aY, aZ) AND ROTATIONAL (gX, gY, gZ) ARROWS
INDICATE THE DIRECTION OF MOTION THAT PRODUCES
A POSITIVE OUTPUT.
Figure 5. Pin Configuration
Figure 6. Axial Orientation
Table 5. Pin Function Descriptions
Pin No.
1
2
3
4
5
6
7, 9
8
10, 11, 12
13, 14, 15
16, 17, 18, 19, 22, 23, 24
20
21
1
Mnemonic
DIO3
DIO4/CLKIN
SCLK
DOUT
DIN
CS
DIO1, DIO2
RST
VCC
GND
DNC
AUX_DAC
AUX_ADC
Type1
I/O
I/O
I
O
I
I
I/O
I
S
S
N/A
O
I
Description
Configurable Digital Input/Output.
Configurable Digital Input/Output or Sync Clock Input.
SPI Serial Clock.
SPI Data Output. Clocks output on SCLK falling edge.
SPI Data Input. Clocks input on SCLK rising edge.
SPI Chip Select.
Configurable Digital Input/Output.
Reset.
Power Supply.
Power Ground.
Do Not Connect.
Auxiliary, 12-Bit DAC Output.
Auxiliary, 12-Bit ADC Input.
I/O is input/output, I is input, O is output, S is supply, and N/A is not applicable.
Rev. PrA | Page 7 of 20
08562-006
PIN 1
NOTES
1. THIS REPRESENTATION DISPLAYS THE TOP VIEW PINOUT
FOR THE MATING SOCKET CONNECTOR.
2. THE ACTUAL CONNECTOR PINS ARE NOT VISIBLE FROM
THE TOP VIEW.
3. MATING CONNECTOR: SAMTEC CLM-112-02 OR EQUIVALENT.
4. DNC = DO NOT CONNECT.
08562-005
CS
RST
DOUT
DIO4/CLKIN
X-AXIS
Y-AXIS
ADIS16385
Preliminary Technical Data
TYPICAL PERFORMANCE CHARACTERISTICS
ADIS16385 - XL Root Allan Variance
ADIS16385 - Z GYRO Root Allan Variance 25C
Average=Solid; Dash=+/-1sigma
Average=Solid; Dash=+/-1sigma
0.00100
Root Allan Variance [g]
Root Allan Variance [o/s]
0.1000
0.0100
0.0010
0.00001
1
10
100
1000
10000
ADIS16385 - XY GYRO Root Allan Variance 25C
Average=Solid; Dash=+/-1sigma
0.1000
0.0100
0.0010
10
100
10
100
1000
Figure 9. Accelerometer Allan Variance
Figure 7. Gyroscope Allan Variance, Z Axis
1
1
Tau [sec]
Tau [sec]
Root Allan Variance [o/s]
0.00010
1000
10000
Tau [sec]
Figure 8. Gyroscope Allan Variance, X-Axis/Y-Axis
Rev. PrA | Page 8 of 20
10000
Preliminary Technical Data
ADIS16385
BASIC OPERATION
The ADIS16385 is an autonomous system that requires no user
initialization. When it has a valid power supply, it initializes
itself and starts sampling, processing, and loading sensor data
into the output registers at a sample rate of 1024 SPS. DIO1
pulses high after each sample cycle concludes. The SPI interface
enables simple integration with many embedded processor
platforms, as shown in Figure 10 (electrical connection) and
Table 6 (pin descriptions).
VDD
I/O LINES ARE COMPATIBLE WITH
3.3V OR 5V LOGIC LEVELS
The ADIS16385 provides two different options for acquiring
sensor data: single register and burst register. A single register
read requires two 16-bit SPI cycles. The first cycle requests the
contents of a register using the bit assignments in Figure 14.
Bit DC7 to Bit DC0 are don’t care for a read, and then the output
register contents follow on DOUT during the second sequence.
Figure 11 includes three single register reads in succession. In
this example, the process starts with DIN = 0x0400 to request
the contents of XGYRO_OUT, and follows with 0x0600 to
request YGYRO_OUT, and 0x0800 to request ZGYRO_OUT.
Full duplex operation enables processors to use the same 16-bit
SPI cycle to read data from DOUT while requesting the next set
of data on DIN. Figure 12 provides an example of the four SPI
signals when reading XGYRO_OUT in a repeating pattern.
5V
10
SYSTEM
PROCESSOR
SPI MASTER
READING SENSOR DATA
11
12
ADIS16385
ADIS16360/
ADIS16365
SS
6
CS
SCLK
3
SCLK
MOSI
5
DIN
MISO
4
DOUT
IRQ
7
DIO1
SPI SLAVE
14
15
07570-009
13
Figure 11. SPI Read Example
Figure 10. Electrical Connection Diagram
Table 6. Generic Master Processor Pin Names and Functions
Pin Name
SS
SCLK
MOSI
MISO
IRQ
Function
Slave select
Serial clock
Master output, slave input
Master input, slave output
Interrupt request
Figure 12. Example SPI Read, Second 16-Bit Sequence
Burst-Read Function
The ADIS16385 SPI interface supports full duplex serial
communication (simultaneous transmit and receive) and uses
the bit sequence shown in Figure 14. Table 7 provides a list of
the most common settings that require attention to initialize a
processor’s serial port for the ADIS16385 SPI interface.
The burst-read function enables the user to read all output registers
using one command on the DIN line and shortens the stall time
between each 16-bit segment to 1 SCLK cycle (see Table 2).
Figure 13 provides the burst-read sequence of data on each SPI
signal. The sequence starts with writing 0x3E00 to DIN, followed
by each output register clocking out on DOUT, in the order in
which they appear in Table 8.
Table 7. Generic Master Processor SPI Settings
Processor Setting
Master
SCLK Rate ≤ 2 MHz1
SPI Mode 3
MSB First Mode
16-Bit Mode
For burst read, SCLK rate ≤ 1 MHz. For low power mode, SCLK rate ≤ 300 kHz.
Figure 13. Burst-Read Sequence
CS
SCLK
DIN
DOUT
R/W
D15
A6
A5
A4
A3
A2
A1
A0
DC7
DC6
DC5
DC4
DC3
DC2
DC1
DC0
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
NOTES
1. DOUT BITS ARE PRODUCED ONLY WHEN THE PREVIOUS 16-BIT DIN SEQUENCE STARTS WITH R/W = 0.
Figure 14. SPI Communication Bit Sequence
Rev. PrA | Page 9 of 20
R/W
D15
A6
A5
D14
D13
07570-011
1
Description
The ADIS16385 operates as a slave
Maximum serial clock rate
CPOL = 1 (polarity), CPHA = 1 (phase)
Bit sequence
Shift register/data length
ADIS16385
Preliminary Technical Data
OUTPUT DATA REGISTERS
Table 12. Analog Input, Offset Binary Format
The output registers in Table 8 provide the most recent sensor
data produced by the ADIS16385. All of the inertial sensor
outputs use a 16-bit, twos complement, data format. Figure 6
provides arrows that describe the direction of motion, which
produces a positive output in each inertial sensor’s output data
register.
Input Voltage
3.3 V
1V
1.6116 mV
805.9 μV
0V
Table 8. Output Data Register Formats
DEVICE CONFIGURATION
Register
XGYRO_OUT1
YGYRO_OUT1
ZGYRO_OUT1
XACCL_OUT
YACCL_OUT
ZACCL_OUT
TEMP_OUT2
AUX_ADC
1
2
Address
0x04
0x06
0x08
0x0A
0x0C
0x0E
0x10
0x12
Measurement
Gyroscope, x-axis
Gyroscope, y-axis
Gyroscope, z-axis
Accelerometer, x-axis
Accelerometer, y-axis
Accelerometer, z-axis
Internal Temperature
Auxiliary ADC
Format
Table 9
Table 9
Table 9
Table 10
Table 10
Table 10
Table 11
Table 12
Decimal
4095
1241
2
1
0
Hex
0xFFF
0x4D9
0x002
0x001
0x000
Binary
XXXX 1111 1111 1111
XXXX 0100 1101 1001
XXXX 0000 0000 0010
XXXX 0000 0000 0001
XXXX 0000 0000 0000
The control registers in Table 13 provide users with a variety of
configuration options. The SPI provides access to these registers,
one byte at a time, using the bit assignments in Figure 14. Each
register has 16-bits, where bits [7:0] represent the lower address
and Bits[15:8] represent the upper address. Figure 15 provides an
example of writing 0x03 to Address 0x36 (SMPL_PRD[15:8]),
using DIN = 0xB703. This example reduces the sample rate by a
factor of eight (see Table 28).
Assumes that the scaling is set to ±300°/sec. This factor scales with the range.
This is most useful for monitoring relative changes in the temperature.
Table 9. Rotation Rate, Twos Complement Format
Decimal
+24000
+2
+1
0
−1
−2
−24000
Hex
0x5DC0
0x0002
0x0001
0x0000
0xFFFF
0xFFFE
0xA240
Binary
0101 1101 1100 0000
0000 0000 0000 0010
0000 0000 0000 0001
0000 0000 0000 0000
1111 1111 1111 1111
1111 1111 1111 1110
1010 0010 0100 0000
Table 10. Acceleration, Twos Complement Format
Acceleration
+5 g
+0.5 mg
+0.25 mg
0g
−0.25 mg
−0.5 mg
−5 g
Decimal
+20000
+2
+1
0
−1
−2
− 20000
Hex
0x4E20
0x0002
0x0001
0x0000
0xFFFF
0xFFFE
0xB1E0
Binary
0100 1110 0010 0000
0000 0000 0000 0010
0000 0000 0000 0001
0000 0000 0000 0000
1111 1111 1111 1111
1111 1111 1111 1110
1011 0001 1110 0000
Figure 15. Example SPI Write Sequence
Dual Memory Structure
Writing configuration data to a control register updates its SRAM
contents, which are volatile. After optimizing each relevant control
register setting in a system, set GLOB[12] = 1 (DIN = 0xBF10) to
back these settings up in nonvolatile flash memory. The flash backup process requires a valid power supply level for the entire 75 ms
process time. Table 13 provides a user register memory map that
includes a flash back-up column. A yes in this column indicates
that a register has a mirror location in flash, and when backed up
properly, it automatically restores itself during start-up or after a
reset. Figure 16 provides a diagram of the dual-memory structure
used to manage operation and store critical user settings.
Decimal
+1180
+2
+1
0
−1
−2
−959
Hex
0x49C
0x002
0x001
0x000
0xFFF
0xFFE
0xC41
VOLATILE
SRAM
NONVOLATILE
FLASH MEMORY
Table 11. Temperature, Twos Complement Format
Temperature
+105°C
+25.1356°C
+25.0678°C
+25°C
+24.9322°C
+24. 8644°C
−40°C
MANUAL
FLASH
BACKUP
Binary
XXXX 0100 1001 1100
XXXX 0000 0000 0010
XXXX 0000 0000 0001
XXXX 0000 0000 0000
XXXX 1111 1111 1111
XXXX 1111 1111 1110
XXXX 1100 0100 0001
Rev. PrA | Page 10 of 20
SPI ACCESS
(NO SPI ACCESS)
START-UP
RESET
Figure 16. SRAM and Flash Memory Diagram
07980-109
Rotation Rate
+300°/sec
+0.025°/sec
+0.0125°/sec
0°/sec
−0.0125°/sec
−0.025°/sec
−300°/sec
Preliminary Technical Data
ADIS16385
USER REGISTERS
Table 13. User Register Memory Map1
Name
FLASH_CNT
Reserved
XGYRO_OUT
YGYRO_OUT
ZGYRO_OUT
XACCL_OUT
YACCL_OUT
ZACCL_OUT
TEMP_OUT
AUX_ADC
Reserved
XGYRO_OFF
YGYRO_OFF
ZGYRO_OFF
XACCL_OFF
YACCL_OFF
ZACCL_OFF
ALM_MAG1
ALM_MAG2
ALM_SMPL1
ALM_SMPL2
ALM_CTRL
AUX_DAC
GPIO_CTRL
MSC_CTRL
SMPL_PRD
SENS_AVG
SLP_CTRL
DIAG_STAT
GLOB_CMD
Reserved
LOT_ID1
LOT_ID2
PROD_ID
SERIAL_NUM
1
2
R/W
R
N/A
R
R
R
R
R
R
R
R
N/A
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
W
R
R/W
N/A
R
R
R
R
Flash Backup
Yes
N/A
No
No
No
No
No
No
No
No
N/A
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
No
Yes
Yes
Yes
No
No
No
N/A
Yes
Yes
Yes
Yes
Address2
0x00
0x02
0x04
0x06
0x08
0x0A
0x0C
0x0E
0x10
0x12
0x014 to 0x19
0x1A
0x1C
0x1E
0x20
0x22
0x24
0x26
0x28
0x2A
0x2C
0x2E
0x30
0x32
0x34
0x36
0x38
0x3A
0x3C
0x3E
0x40 to 0x51
0x52
0x54
0x56
0x58
Default
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
0x0000
0x0000
0x0000
0x0000
0x0000
0x0000
0x0000
0x0000
0x0000
0x0000
0x0000
0x0000
0x0000
0x0006
0x0001
0x0402
0x0000
0x0000
0x0000
N/A
N/A
N/A
0x4001
N/A
Register Description
Flash memory write count
Reserved
X-axis gyroscope output
Y-axis gyroscope output
Z-axis gyroscope output
X-axis accelerometer output
Y-axis accelerometer output
Z-axis accelerometer output
Internal temperature output
Auxiliary ADC output
Reserved
X-axis gyroscope bias correction factor
Y-axis gyroscope bias correction factor
Z-axis gyroscope bias correction factor
X-axis acceleration bias correction factor
Y-axis acceleration bias correction factor
Z-axis acceleration bias correction factor
Alarm 1, amplitude threshold
Alarm 2, amplitude threshold
Alarm 1, dynamic time change
Alarm 2, dynamic time change
Alarm control
Auxiliary DAC output level setting
Auxiliary digital input/output control
Miscellaneous control: data ready, self-test
Sample clock source, decimation rate
Dynamic range and digital filter control
Sleep mode control
System status (error flags)
System command (global)
Reserved
Lot Identification Code 1
Lot Identification Code 2
Product identification, ADIS16385
Serial number
Reference
Table 20
N/A
Table 9
Table 9
Table 9
Table 10
Table 10
Table 10
Table 11
Table 12
Table 31
Table 31
Table 31
Table 32
Table 32
Table 32
Table 34
Table 35
Table 36
Table 36
Table 37
Table 25
Table 24
Table 21
Table 28
Table 29
Table 16
Table 22
Table 15
Table 17
Table 17
Table 19
Table 18
N/A = not applicable.
Each register contains two bytes. The address of the lower byte is displayed. The address of the upper byte is equal to the address of the lower byte plus 1.
Rev. PrA | Page 11 of 20
ADIS16385
Preliminary Technical Data
SYSTEM FUNCTIONS
The ADIS16385 provides a number of system-level controls for
managing its operation, using the registers in Table 14.
Table 14. System Tool Registers
Register Name
MSC_CTRL
SLP_CTRL
DIAG_STAT
GLOB_CMD
LOT_ID1
LOT_ID2
PROD_ID
SERIAL_NUM
Address
0x34
0x3A
0x3C
0x3E
0x52
0x54
0x56
0x58
Description
Self-test, calibration, data-ready
Sleep mode control
Error flags
Single-command functions
Lot Identification Code 1
Lot Identification Code 2
Product identification:
Serial number
The GLOB_CMD register in Table 15 provides trigger bits for
device reset, flash memory management, DAC control, and
calibration control. Start each of these functions by writing a 1 to
the assigned bit in GLOB_CMD. After completing the task, the bit
automatically returns to zero. For example, set GLOB_CMD[7] = 1
(DIN = 0xBE80) to initiate a software reset, which stops the sensor
operation and runs the device through its startup sequence. Set
GLOB_CMD[3] = 1 (DIN = 0xBE04) to back up the user register
contents in nonvolatile flash. This sequence includes loading the
control registers with the data in their respective flash memory
locations prior to producing new data.
1
2
Description (Default = 0x0000)
Not used
Normal sleep mode, (1 = start sleep mode)
Timed sleep mode (write 0x01 to 0xFF to start).
Sleep mode duration, binary, 0.5 sec/LSB
The PROD_ID register in Table 19 contains the binary equivalent
of 16,385. It provides a product-specific variable for systems that
need to track this in their system software. The LOT_ID1 and
LOT_ID2 registers in Table 17 combine to provide a unique, 32-bit
lot identification code. The SERIAL_NUM register in Table 18
contains a binary number that represents the serial number on
the device label. The assigned serial numbers in SERIAL_NUM
are lot specific.
Table 17. LOT_ID1, LOT_ID2 Bit Descriptions
Bits
[15:0]
Description (Default = 0x0000)
Lot identification, binary code
Table 18. SERIAL_NUM Bit Descriptions
Bits
[15:14]
[13:0]
Description (Default = 0x0000)
Reserved
Serial number, 1 to 9999 (0x270F)
Table 19. PROD_ID Bit Descriptions
Table 15. GLOB_CMD Bit Descriptions
Description (Default = 0x0000)
Not used
Software reset
Not used
Flash update
Auxiliary DAC data latch
Factory calibration restore
Automatic bias correction
Bits
[15:9]
[8]
[7:0]
PRODUCT IDENTIFICATION
GLOBAL COMMANDS
Bits
[15:8]
[7]
[6:4]
[3]
[2]
[1]
[0]
Table 16. SLP_CTRL Bit Descriptions
Execution Time
N/A
4 ms
N/A
75 ms
75 ms
75 ms
N/A2
1
N/A = not applicable.
Execution time is dependent on SMPL_PRD[12:8] setting.
Bits
[15:0]
Description (Default = 0x0000)
Product identification = 0x4001
MEMORY MANAGEMENT
The FLASH_CNT register in Table 20 provides a 16-bit counter
that helps track the number of write cycles to the nonvolatile
flash memory. The flash updates every time any of the following
bits are set to 1: GLOB_CMD[3] and GLOB[1:0].
Table 20. FLASH_CNT Bit Descriptions
Bits
[15:0]
POWER MANAGEMENT
The SLP_CTRL register, in Table 16, provides two different sleep
modes for system-level management: normal and timed. Set
SLP_CTRL[8] = 1 (DIN = 0xBB01) to start normal sleep mode.
When the device is in sleep mode, the following events can
cause it to wake-up: assert CS from high to low, assert RST
from high to low, or cycle the power. Use SLP_CTRL[7:0] to put
the device into sleep mode for a specified period. For example,
SLP_CNT[7:0] = 0x64 (DIN = 0xBA64) puts the ADIS16385 to
sleep for 50 sec.
Rev. PrA | Page 12 of 20
Description
Binary counter
Preliminary Technical Data
ADIS16385
Checksum Test
Set MSC_CTRL[6] = 1 (DIN = 0xB508) to perform a checksum verification of the internal program memory. This takes a
summation of the internal program memory and compares it
with the original summation value for the same locations (from
factory configuration). Check the results in the DIAG_STAT
register, which is in Table 22. DIAG_STAT[6] equals 0 if the sum
matches the correct value and 1 if it does not. Make sure that
the power supply is within specification for the entire 20 ms
that this function takes to complete.
SELF-TEST FUNCTION
The MSC_CTRL register in Table 21 provides a self-test function
for all six MEMS inertial sensors. This function allows the user
to verify the mechanical integrity of each MEMS sensor. When
enabled, the self-test applies an electrostatic force to each internal
sensor element, which causes them to move. The movement in
each element simulates its response to actual rotation/acceleration
and generates a predictable electrical response in the sensor outputs.
Table 1 provides the expected response for both gyroscopes and
accelerometers that can help establish pass/fail limits during
system-level diagnostic testing.
Table 21. MSC_CTRL Bit Descriptions
Bits
[15:12]
[11]
[10]
[9]
[8]
[7]
[6]
[5:3]
[2]
[1]
[0]
1
Description (Default = 0x0006)
Not used
Memory test (cleared upon completion)1
(1 = enabled, 0 = disabled)
Internal self-test (cleared upon completion)1
(1 = enabled, 0 = disabled)
Not used
Manual self-test
(1 = enabled, 0 = disabled)
Linear acceleration bias compensation for gyroscopes
(1 = enabled, 0 = disabled)
Point of percussion, per Figure 6
(1 = enabled, 0 = disabled)
Not used
Data-ready enable
(1 = enabled, 0 = disabled)
Data-ready polarity
(1 = active high, 0 = active low)
Data-ready line select
(1 = DIO2, 0 = DIO1)
The bit automatically restores to zero after finishing the test
There are two self-test options in the MSC-CTRL register:
internal and manual. Set MSC_CTRL[10] = 1 (DIN = 0xB504)
to run the internal self-test routine, which exercises all inertial
sensors, measures each response, computes the response to the
self-test stimulus, makes pass/fail decisions, and reports them to
the error flags in DIAG_STAT[5] and DIAG_STAT[15:10]. While
DIAG_STAT[15:10] provide individual error flags for each
inertial sensor, DIAG_STAT[5] provides a single-bit for indicating a
failure in any of the inertial sensors. MSC_CTRL[10] resets
itself to 0 after completing the routine.
Set MSC_CTRL[8] = 1 (DIN = B501) to manually activate the
self-test function on all six sensors. Set MSC_CTRL[8] = 0
(DIN = B500) to manually de-activate the self-test function on
all six sensors. Measure the output bias for each MSC_CTRL[8]
setting (0 and 1), take the difference between them, and compare
this difference with the expected self-test response in Table 1.
STATUS
The DIAG_STAT register in Table 22 provides error flags for a
number of functions. Each flag uses 1 to indicate an error
condition and 0 to indicate a normal condition. Reading this
register provides access to each flag’s status and resets all of the
bits to 0 for monitoring future operation. If the error condition
remains, the error flag will return to 1 at the conclusion of the
next sample cycle. DIAG_STAT[0] does not require a read of
this register to return to 0. If the power supply voltage goes back
into range, this flag clears automatically. The SPI communication
error flag in DIAG_STAT[3] indicates that the number of
SCLKs in a SPI sequence did not equal a multiple of 16 SCLKs.
Table 22. DIAG_STAT Bit Descriptions
Bits
[15]
[14]
[13]
[12]
[11]
[10]
[9]
[8]
[7]
[6]
[5]
[4]
[3]
[2]
[1]
[0]
Rev. PrA | Page 13 of 20
Description (Default = 0x0000)
Z-axis accelerometer self-test failure (1 = fail, 0 = pass)
Y-axis accelerometer self-test failure (1 = fail, 0 = pass)
X-axis accelerometer self-test failure (1 = fail, 0 = pass)
Z-axis gyroscope self-test failure (1 = fail, 0 = pass)
Y-axis gyroscope self-test failure (1 = fail, 0 = pass)
X-axis gyroscope self-test failure (1 = fail, 0 = pass)
Alarm 2 status (1 = active, 0 = inactive)
Alarm 1 status (1 = active, 0 = inactive)
Not used
Flash test, checksum flag (1 = fail, 0 = pass)
Self-test diagnostic error flag (1 = fail, 0 = pass)
Sensor over-range (1 = over-range, 0 = normal)
SPI communication failure (1 = fail, 0 = pass)
Flash update failure (1 = fail, 0 = pass)
Not used
Power supply low, (1 = VDD <4.85V, 0 = VDD ≥ 4.85V)
ADIS16385
Preliminary Technical Data
INPUT/OUTPUT CONFIGURATION
Table 23 provides a summary of registers that provide input/output
configuration and control.
Table 23. Input/Output Registers
Register Name
AUX_DAC
GPIO_CTRL
MSC_CTRL
Address
0x30
0x32
0x34
Description
Output voltage control, AUX_DAC
General-purpose I/O control
Self-test, calibration, data-ready
Example I/O Configuration
For example, set GPIO_CTRL[3:0] = 0100 to set DIO3 as an
output signal pin and DIO1, DIO2, and DIO4 as input signal
pins. Set the output on DIO3 to 1 by setting GPIO_CTRL[10] = 1
(DIN = 0xB304). Then, read GPIO_CTRL (DIN = 0x3200) and
mask off GPIO_CTRL[9:8] and GPIO_CTRL[11] to monitor the
digital signal levels on DIO4, DIO2, and DIO1.
AUXILIARY DAC
DATA-READY I/O INDICATOR
The factory-default setting of MSC_CTRL[2:0] (110) establishes
DIO1 as a positive-polarity data-ready signal. See Table 21 for
additional data-ready configuration options. For example, set
MSC_CTRL[2:0] = 100 (DIN = 0xB404) to change the polarity of
the data-ready signal on DIO1 for interrupt inputs that require
negative logic inputs for activation. The pulse width is between
100 μs and 200 μs over all conditions.
GENERAL-PURPOSE I/O
DIO1, DIO2, DIO3, and DIO4 are configurable, general-purpose
I/O lines that serve multiple purposes. The data-ready controls
in MSC_CTRL[2:0] have the highest priority for configuring
DIO1 and DIO2. The alarm indicator controls in ALM_CTRL[2:0]
have the second-highest priority for DIO1 and DIO2. GPIO_CTRL
in Table 24 has the lowest priority for configuration DIO1, DIO2,
and DIO4 and has absolute control over DIO3.
The AUX_DAC register in Table 25 provides user controls for
setting the output voltage on the AUX_DAC pin. The 12-bit
AUX_DAC line can drive its output to within 5 mV of the ground
reference when it is not sinking current. As the output approaches
0 V, the linearity begins to degrade (~100 LSB starting point). As
the sink current increases, the nonlinear range increases. The
DAC latch command in GLOB_CMD[2] (see Table 15) moves
the values of the AUX_DAC register into the DAC input register,
enabling both bytes to take effect at the same time. This prevents
undesirable output levels, which reflect single-byte changes of
the AUX_DAC register.
Table 25. AUX_DAC Bit Descriptions
Bits
[15:12]
[11:0]
Description (Default = 0x0000)
Not used
Data bits, scale factor = 0.8059 mV/LSB
Offset binary format, 0 V = 0 LSB
Table 24. GPIO_CTRL Bit Descriptions
Table 26. Setting AUX_DAC = 1 V
Bits
[15:12]
[11]
[10]
[9]
[8]
[7:4]
[3]
DIN
0xB0D9
0xB104
0xBE04
[2]
[1]
[0]
Description (Default = 0x0000)
Not used
General-Purpose I/O Line 4 (DIO4) data level
General-Purpose I/O Line 3 (DIO3) data level
General-Purpose I/O Line 2 (DIO2) data level
General-Purpose I/O Line 1 (DIO1) data level
Not used
General-Purpose I/O Line 4 (DIO4) direction control
(1 = output, 0 = input)
General-Purpose I/O Line 3 (DIO3) direction control
(1 = output, 0 = input)
General-Purpose I/O Line 2 (DIO2) direction control
(1 = output, 0 = input)
General-Purpose I/O Line 1 (DIO1) direction control
(1 = output, 0 = input)
Rev. PrA | Page 14 of 20
Description
AUX_DAC[7:0] = 0xD9 (217 LSB)
AUX_DAC[15:8] = 0x04 (1024 LSB)
GLOB_CMD[2] = 1; move values into the DAC input
register, resulting in a 1 V output level
Preliminary Technical Data
ADIS16385
DIGITAL PROCESSING CONFIGURATION
0
Table 27. Digital Processing Registers
Description
Sample rate control
Digital filtering and range control
–20
–40
Sample Rate
The internal sampling system produces new data in the output
data registers at a rate of 1024 SPS. The SMPL_PRD register in
Table 28 provides two functional controls that affect sampling
and register update rates. SMPL_PRD[12:8] provides a control
for reducing the update rate, using an averaging filter with a
decimated output. These bits provide a binomial control that
divides the data rate by a factor of 2 every time this number
increases by one. For example, set SMPL_PRD[12:8] = 0100
(DIN = 0xB704) to set the decimation factor to 16. This reduces
the update rate to 64 SPS and the bandwidth to 31 Hz.
–60
–80
–100
N=2
N=4
N = 16
N = 64
–120
–140
0.001
0.01
0.1
1
FREQUENCY (f/fS)
07570-014
Address
0x36
0x38
MAGNITUDE (dB)
Register Name
SMPL_PRD
SENS_AVG
Figure 17. Bartlett Window, FIR Filter Frequency Response
(Phase Delay = N Samples)
Table 28. SMPL_PRD Bit Descriptions
Dynamic Range
Bits
[15:13]
[12:8]
[7:1]
[0]
The SENS_AVG[10:8] bits provide three dynamic range settings
for this gyroscope. The lower dynamic range settings (±75°/sec
and ±150°/sec) limit the minimum filter tap sizes to maintain
resolution. For example, set SENS_AVG[10:8] = 010 (DIN =
0xB902) for a measurement range of ±150°/sec. Because this
setting can influence the filter settings, program SENS_AVG[10:8]
before programming SENS_AVG[2:0] if more filtering is
required.
Description (Default = 0x0001)
Not used
Average/decimation rate setting, binomial
Not used
Clock: 1 = internal (1024 SPS), 0 = external
Input Clock Configuration
SMPL_PRD[0] provides a control for synchronizing the internal
sampling to an external clock source. Set GPIO_CTRL[3] = 0
(DIN = 0x0B200) and SMPL_PRD[0] = 0 (DIN = 0xB600) to
enable the external clock. See Table 2 and Figure 4 for timing
information.
Table 29. SENS_AVG Bit Descriptions
Bits
[15:11]
[10:8]
Digital Filtering
The SENS_AVG register in Table 29 provides user controls for
the low-pass filter. This filter contains two cascaded averaging
filters that provide a Bartlett window, FIR filter response (see
Figure 18). For example, set SENS_AVG[2:0] = 100 (DIN = 0xB804)
to set each stage to 16 taps. When used with the default sample
rate of 1024 SPS and zero decimation (SMPL_PRD[12:8] = 00000),
this value reduces the sensor bandwidth to approximately 20 Hz.
[7:3]
[2:0]
1
NB
NB
∑ x(n)
n =1
Description (Default = 0x0402)
Not used
Measurement range (sensitivity) selection
100 = ±300°/sec (default condition)
010 = ±150°/sec, filter taps ≥ 4 (Bits[2:0] ≥ 0x02)
001 = ±75°/sec, filter taps ≥ 16 (Bits[2:0] ≥ 0x04)
Not used
Number of taps in each stage; value of m in N = 2m
1
NB
NB
∑ x(n)
n =1
1
ND
ND
∑ x(n)
÷ ND
n =1
B = SENS_AVG[2 : 0]
D = SMPL_PRD[12 : 8]
N B = 2B
N D = 2D
N B = Number of taps (per stage)
N D = Number of taps
Figure 18. Sampling and Frequency Response Block Diagram
Rev. PrA | Page 15 of 20
ADIS16385
Preliminary Technical Data
CALIBRATION
The mechanical structure and assembly process of the ADIS16385
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 sensor’s behavior over temperature
and generates sensor-specific correction formulas. The bias
correction registers in Table 30 provide users with the ability to
address bias shifts that can result from mechanical stress. Figure 19
illustrates the summing function of each sensor’s offset correction
register.
Table 30. Registers for User Calibration
Register
XGYRO_OFF
YGYRO_OFF
ZGYRO_OFF
XACCL_OFF
YACCL_OFF
ZACCL_OFF
GLOB_CMD
Address
0x1A
0x1C
0x1E
0x20
0x22
0x24
0x3E
Description
Gyroscope bias, x-axis
Gyroscope bias, y-axis
Gyroscope bias, z-axis
Accelerometer bias, x-axis
Accelerometer bias, y-axis
Accelerometer bias, z-axis
Automatic calibration
ABC Example
Set SMPL_PRD[15:8] = 0x10 (DIN = 0xB710) to set the decimation
rate to 65,536 (216), which provides an averaging time of 64 seconds
(65536 ÷ 1024 SPS) for this function. Then, set GLOB_CMD[0] = 1
(DIN = 0xBE01) and keep the platform stable for at least 65 seconds
while the gyroscope bias data accumulates. After this completes,
the ADIS16385 automatically updates the flash memory. The
SPI is inactive and does not respond to user inputs while the
ABC is processing. The only way to interrupt it is to remove
power or initiate a hardware reset using the RST pin. When
using SMPL_PRD[12:8] = 0x10, the 1-σ accuracy for this
correction is approximately 0.008°/sec for the X-axis and Y-axis
gyroscopes and 0.003°/sec for the Z-axis gyroscope. See Table 15
for more information on GLOB_CMD.
Manual Bias Correction
The manual bias correction (MBC) function requires the user to
collect the desired number of samples, calculate the averages to
develop bias estimates for each gyroscope channel, and then write
them into the bias offset registers, located in Table 31 for the gyroscopes. For example, set XGYRO_OFF = 0x1FF6 (DIN = 0x9B1F,
0x9AF6) to adjust the XGYRO_OUT offset by −0.03125°/sec
(−10 LSBs). Table 32 provides a manual adjustment function for
the accelerometer channels as well.
Table 31. XGYRO_OFF, YGYRO_OFF, and ZGYRO_OFF
Bit Descriptions
Figure 19. User Calibration, XGYRO_OFF Example
There are two options for optimizing gyroscope bias accuracy
prior to system deployment: automatic bias correction (ABC)
and manual bias correction (MBC).
Automatic Bias Correction (ABC)
2.
3.
4.
Set the output range to ±75°/sec and wait for a complete
output data cycle to complete (the SMPL_PRD[12:8] bits
set this time).
Read the output register of the gyroscope.
Multiply the measurement by −1 to change its polarity.
Write the final value into the offset register.
The Allan Variance curves in Figure 7, Figure 9, and Figure 8
provide a trade-off between bias accuracy and averaging time.
SMPL_PRD[12:8] provide a user control for averaging time
when using the ABC function. Use this setting, in combination
with GLOB_CMD[0], to create the automatic bias correction
function.
Description (Default = 0x0000)
Twos complement, 0.003125°/sec per LSB. Typical
adjustment range = ±102°/sec.
Table 32. XACCL_OFF, YACCL_OFF, and ZACCL_OFF
Bit Descriptions
Bits
[15:0]
Set GLOB_CMD[0] = 1 (DIN = 0xBE01) to start the ABC
function, which uses the following internal sequence to
calibrate each gyroscope for bias error:
1.
Bits
[15:0]
Description (Default = 0x0000)
Data bits. Twos complement, 0.25 mg/LSB. Typical
adjustment range = ±8.192 g.
Restoring Factory Calibration
Set GLOB_CMD[1] = 1 (DIN = 0xBE02) to execute the factory
calibration restore function. This is a single-command function,
which resets each user calibration register to 0x0000 and all sensor
data to zero. Then, it automatically updates the flash memory
within 50 ms. See Table 15 for more information on GLOB_CMD.
Point-of-Percussion (Gyroscope)
Set MSC_CTRL[6] = 1 (DIN = 0xB486) 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 6. See Table 21 for more information on MSC_CTRL.
Rev. PrA | Page 16 of 20
Preliminary Technical Data
ADIS16385
ALARMS
The ADIS16385 provides two independent alarms, Alarm 1 and
Alarm 2, which have a number of programmable settings. Table 33
provides a list of registers for these user settings.
Table 37. ALM_CTRL Bit Descriptions
Bits
[15:12]
Table 33. Registers for Alarm Configuration
Register
ALM_MAG1
ALM_MAG2
ALM_SMPL1
ALM_SMPL2
ALM_CTRL
Address
0x26
0X28
0x2A
0x2C
0x2E
Description
Alarm 1, trigger setting
Alarm 2, trigger setting
Alarm 1, sample period
Alarm 2, sample period
Alarm configuration
The ALM_CTRL register in Table 37 provides data source
selection (Bits[15:8]), static/dynamic setting for each alarm
(Bits[7:6]), trigger polarity (Bits[5:4]), data source filtering
(Bit[3]), and alarm indicator signal (Bits[2:0]).
Description (Default = 0x0000)
Alarm 2 data source selection
0000 = disable
0001 = x-axis gyroscope output
0010 = y-axis gyroscope output
0011 = z-axis gyroscope output
0100 = x-axis accelerometer output
0101 = y-axis accelerometer output
0110 = z-axis accelerometer output
0111 = internal temperature output
1000 = auxiliary ADC input
1001 = self test
Alarm 1 data source selection (same as Alarm 2)
Alarm 2, dynamic/static (1 = dynamic, 0 = static)
Alarm 1, dynamic/static (1 = dynamic, 0 = static)
Alarm 2, polarity (1 = greater than, 0 = less than)
Alarm 1, polarity (1 = greater than, 0 = less than)
Data source filtering (1 = filtered, 0 = unfiltered)
Alarm indicator (1 = enabled, 0 = disabled)
Alarm indicator active polarity (1 = high, 0 = low)
Alarm output line select (1 = DIO2, 0 = DIO1)
The static alarms setting compares the data source selection
(ALM_CTRL[15:8]) with the values in the ALM_MAGx registers
in Table 34 and Table 35. The data format in these registers
matches the format of the data selection in ALM_CTRL[15:8].
The ALM_CTRL[5:4] bits provide polarity settings. See Table 38,
Alarm 1, for a static alarm configuration example.
[11:8]
[7]
[6]
[5]
[4]
[3]
[2]
[1]
[0]
Table 34. ALM_MAG1 Bit Descriptions
Alarm Example
Static Alarm Use
Bits
[15:0]
Table 38 offers an example that configures Alarm 1 to trigger
when filtered ZACCL_OUT data drops below 0.7g, and Alarm 2 to
trigger when filtered ZGYRO_OUT data changes by more than
50°/sec over a 100 ms period, or 5,000°/sec2. The filter setting
helps reduce false triggers from noise and refine the accuracy of
the trigger points. The ALM_SMPL2 setting of 102 samples
provides a comparison period that is 99.6 ms for an internal
sample rate of 1024 SPS. Because Alarm 1 is a static alarm in
this example, there is no need to program ALM_SMPL1.
Description (Default = 0x0000)
Threshold setting; matches for format of
ALM_CTRL[11:8] selection
Table 35. ALM_MAG2 Bit Descriptions
Bits
[15:0]
Description (Default = 0x0000)
Threshold setting; matches for format of
ALM_CTRL[15:12] selection
Dynamic Alarm Use
The dynamic alarm setting monitors the data selection for a
rate-of-change comparison. The rate-of-change comparison is
represented by the magnitude in the ALM_MAGx registers over
the time represented by the number-of-samples setting in the
ALM_SMPLx registers, located in Table 36. See Table 38, Alarm 2,
for a dynamic alarm configuration example.
Table 38. Alarm Configuration Example 1
DIN
0xAF36,
0xAEAF
Table 36. ALM_SMPL1 and ALM_SMPL2 Bit Descriptions
Bits
[15:8]
[7:0]
Description (Default = 0x0000)
Not used
Binary, number of samples (both 0x00 and 0x01 = 1)
Alarm Reporting
The DIAG_STAT[9:8] bits provide error flags that indicate an
alarm condition. The ALM_CTRL[2:0] bits provide controls for
a hardware indicator using DIO1 or DIO2.
0xA90F,
0xA8A0
0xA70A,
0xA6F0
0xAC76
Rev. PrA | Page 17 of 20
Description
ALM_CTRL = 0x36AF.
Alarm 2: dynamic, Δ-ZGYRO_OUT (Δ-time, ALM_SMPL2) >
ALM_MAG2.
Alarm 1: static, ZACCL_OUT < ALM_MAG1. Use filtered
data source for comparison. DIO2 output indicator,
positive polarity.
ALM_MAG2 = 0x0FA0 (+50°/sec).
ALM_MAG1 = 0x0AF0 (0.7 g).
ALM_SMPL2[7:0] = 0x66 (102 samples).
ADIS16385
Preliminary Technical Data
APPLICATIONS INFORMATION
PROTOTYPE INTERFACE BOARD
INSTALLATION TIPS
The ADIS16385/PCBZ includes one ADIS16385BMLZ, one
interface printed circuit board (PCB), and four M2x18 machine
screws. The interface PCB provides larger connectors than the
ADIS16385BMLZ for simpler prototyping, four-tapped M2 holes
for attachment of the ADIS16385BMLZ, and four holes (machine
screw size M2.5 or #4) for mounting the ADIS16385BMLZ to a
solid structure. J1 and J2 are dual-row, 2 mm (pitch) connectors
that work with a number of ribbon cable systems, including 3M
Part Number 152212-0100-GB (ribbon crimp connector) and 3M
Part Number 3625/12 (ribbon cable).
Figure 22 and Figure 23 provide the mechanical design information
used for the ADIS16385/PCBZ. Use Figure 22 and Figure 23 when
implementing a connector-down approach, where the mating
connector and the ADIS16385BMLZ are on the same surface.
When designing a connector-up system, use the mounting
holes shown in Figure 22 as a guide in designing the bulkhead
mounting system and use Figure 23 as a guide in developing
the mating connector interface on a flexible circuit or other
connector system.
Figure 20 provides the top-level view of the interface board.
Install the ADIS16385BMLZ onto this board using the silk
pattern as an orientation guide. Figure 21 provides the pin
assignments for J1 and J2. The pin descriptions match those
listed in Table 5. The ADIS16385 does not require external
capacitors for normal operation; therefore, the interface PCB
does not use the C1/C2 pads.
31.200 BSC
15.600 BSC
2x 0.560 BSC
ALIGNMENT HOLES
FOR MATING SOCKET
39.60 BSC
19.800 BSC
17.520
2.280
4x 2.500 BSC
08888-022
iSensor
5.00 BSC
5.00 BSC
Figure 22. Suggested Mounting Hole Locations, Connector Down
0.4334 [11.0]
0.019685
[0.5000]
(TYP)
0.0240 [0.610]
0.054 [1.37]
Figure 20. Physical Diagram for the ADIS16385/PCBZ
0.022±
DIA (TYP)
NONPLATED
0.022 DIA THRU HOLE (TYP)
THRU HOLE 2×
NONPLATED THRU HOLE
Figure 23. Suggested Layout and Mechanical Design for the Mating Connector
J2
J1
0.0394 [1.00]
1
2
SCLK
DNC
1
2
GND
CS
3
4
DOUT
DNC
3
4
DNC
DNC
5
6
DIN
GND
5
6
CLKIN
GND
7
8
GND
DNC
7
8
DNC
GND
9
10
VCC
DNC
9
10
DNC
VCC
11
12
VCC
DIO2
11
12
DIO1
08888-021
RST
Figure 21. J1/J2 Pin Assignments
Rev. PrA | Page 18 of 20
08888-023
08888-020
0.0394 [1.00] 0.1800
[4.57]
Preliminary Technical Data
ADIS16385
OUTLINE DIMENSIONS
35.600
31.200
15.600
15.600
5.50
5.50
19.800
17.520
44.000
47.186
2.40 THRU HOLE
(4×)
2.200
(4×)
17.800
2.500
(RADIUS)
BOTTOM VIEW
39.000
FRONT VIEW
38.428
20.678
3.750
15.478
SIDE VIEW
1.00 BSC
LEAD PITCH
47.186
091609-A
0.30 SQ
BSC (24×)
Figure 24. 24-Lead Module with Connector Interface
(ML-24-5)
Dimensions shown in millimeters
ORDERING GUIDE
Model1
ADIS16385BMLZ
ADIS16385/PCBZ
1
Temperature Range
−40°C to +105°C
Package Description
24-Lead Module with Connector Interface
Interface PCB
Z = RoHS Compliant Part.
Rev. PrA | Page 19 of 20
Package Option
ML-24-5
ADIS16385
Preliminary Technical Data
NOTES
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registered trademarks are the property of their respective owners.
PR08562-0-6/10(PrA)
Rev. PrA | Page 20 of 20