ADIS16350AMLZ1 - Analog Devices - Datasheet.Directory

Tri-Axis Inertial Sensor

ADIS16355

Rev. PrG

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FEATURES

Tri-axis gyroscope with digital range scaling

±75, ±150, ±300°/s settings

14-bit resolution

Tri-axis accelerometer

±10 g measurement range

14-bit resolution

350 Hz bandwidth

Factory calibrated sensitivity, bias, and alignment

ADIS16350: +25°C, ADIS16355: -40°C to +85°C

Digitally controlled bias calibration

Digitally controlled sample rate

Digitally controlled filtering

Programmable condition monitoring

Auxiliary digital input/output

Digitally activated self-test

Programmable power management

Embedded temperature sensor

SPI-compatible serial interface

Auxiliary 12-bit ADC input and DAC output

Single-supply operation: 4.75 V to 5.25 V

2000 g shock survivability

APPLICATIONS

Guidance and control

Platform control and stabilization

Motion control and analysis

Inertial measurement units

General navigation

Image stabilization

RoboticsFunctional Block Diagram

6522-001

UX_ADC AUX_DAC

TEMPERATURE

SENSORS

SIGNAL

CONDITIONING

AND

CONVERSION

CALIBRATION

AND

DIGITAL

PROCESSING

POWER

MANAGEMENT ALARMS

SELF-TEST

TRI-AXIS MEMS

ANGULAR RATE SENSOR

TRI-AXIS MEMS

ACCELLERATION

SENSOR

DIGITAL

CONTROL

SPI

PORT

AUX

I/O

GND

DOUT

DIO1 DIO2

SCLK

DIN

VCC

RST

Figure 1.

GENERAL DESCRIPTION

The ADIS16350/5 iSensorTM is a complete triple axis gyroscope

and triple axis accelerometer inertial sensing system. This

sensor combines the Analog Devices Inc. iMEMS® and mixed

signal processing technology to produce a highly integrated

solution, providing calibrated, digital inertial sensing. An SPI

interface and simple output register structure allow for easy

system interface and programming. The ADIS16355 provides

calibration over a temperature range of -40°C to +85°C.

The SPI port provides access to the following embedded

sensors: X, Y, and Z axis angular rates; X, Y, and Z axis linear

acceleration; internal temperature; power supply; and auxiliary

analog input. The inertial sensors are precision aligned across

axes, and are calibrated for offset and sensitivity. An embedded

controller dynamically compensates for all major influences on

the MEMS sensors; thus maintaining highly accurate sensor

outputs without further testing, circuitry, or user intervention.

System integration is simplified with the following additional

programmable features:

• In-system auto bias calibration

• Digital filtering and sample rate

• Self test

• Power management

• Condition monitoring

• Auxiliary digital input/output

This compact module is approximately 23 mm × 23 mm ×

23 mm and provides a convenient flex-based connector system.

ADIS16355

Rev. PrG | Page 2 of 28

TABLE OF CONTENTS

Features .............................................................................................. 1

Applications....................................................................................... 1

Functional Block Diagram .............................................................. 1

General Description......................................................................... 1

Revision History ............................................................................... 2

Specifications..................................................................................... 3

Timing Specifications .................................................................. 5

Timing Diagrams.......................................................................... 5

Absolute Maximum Ratings............................................................ 6

ESD Caution.................................................................................. 6

Pin Configuration and Function Descriptions............................. 7

Typical Performance Characteristics ............................................. 8

Theory of Operation ...................................................................... 12

Overview...................................................................................... 12

Gyroscope Sensor....................................................................... 12

Accelerometer Sensor ................................................................ 12

Factory Calibration .................................................................... 12

Control Register Structure ........................................................ 12

Auxiliary ADC Function........................................................... 12

Basic Operation .............................................................................. 13

Serial Peripheral Interface (SPI)............................................... 13

Data Output Register Access .................................................... 14

Programming and Control............................................................ 16

Control Register Overview ....................................................... 16

Control Register Structure ........................................................ 16

Calibration................................................................................... 17

Global Commands ..................................................................... 17

Operational Control................................................................... 18

Status and Diagnostics............................................................... 20

Applications Information.............................................................. 23

Installation Guidelines............................................................... 23

Outline Dimensions ....................................................................... 25

Ordering Guide .......................................................................... 25

REVISION HISTORY

10/31—Revision PrG: Document performance, pending release

ADIS16355

Rev. PrG | Page 3 of 28

SPECIFICATIONS

Table 1. TA = −40°C to +85°C, VCC = 5.0 V, angular rate = 0°/s, dynamic range 300°/sec, ±1 g, unless otherwise noted

Parameter Conditions Min Typ Max Unit

GYROSCOPE SENSITIVITY Each axis

Initial 25°C, dynamic range = ±300°/s 0.0725 0.07326 0.0740 °/s/LSB

25°C, dynamic range = ±150°/s 0.03663 °/s/LSB

25°C, dynamic range = ±75°/s 0.01832 °/s/LSB

Temperature Coefficient ADIS16350, See Figure 5 600 ppm/°C

ADIS16355, See TBD 40 ppm/°C

Gyro Axis Nonorthogonality 25°C, difference from 90° ideal ±0.05 Degree

Gyro Axis Misalignment 25°C, relative to base -plate and guide pins ±0.5 Degree

Nonlinearity Best fit straight line 0.1 % of FS

GYROSCOPE BIAS

In Run Bias Stability 25°C, 1 σ 0.015 °/s

Angular Random Walk 25°C 4.2 °/√hr

Temperature Coefficient ADIS16350, See Figure 6 0.1 °/s/°C

ADIS16355, See 0.01 °/s/°C

Linear Acceleration Effect Any axis, 1 σ, (linear acceleration bias

compensation enabled)

0.05 °/s/g

Voltage Sensitivity VCC = 4.75 V to 5.25 V 0.25 °/s/V

GYROSCOPE NOISE PERFORMANCE

Output Noise 25°C, ±300°/s range, no filtering 0.60 °/s rms

25°C, ±150°/s range, 4-tap filter setting 0.35 °/s rms

25°C, ±75°/s range, 16-tap filter setting 0.17 °/s rms

Rate Noise Density 25°C, f = 25 Hz, ±300°/s, no filtering 0.05 °/s/√Hz rms

GYROSCOPE FREQUENCY RESPONSE

3 dB Bandwidth 350 Hz

Sensor Resonant Frequency 14 kHz

GYROSCOPE SELF-TEST STATE

Change for Positive Stimulus ±300°/s range setting 432 723 1105 LSB

Change for Negative Stimulus ±300°/s range setting −432 −723 −1105 LSB

Internal Self-Test Cycle Time 25 ms

ACCELEROMETER SENSITIVITY Each axis

Dynamic Range ±8 ±10 g

Initial 25°C 2.471 2.522 2.572 mg/LSB

Temperature Coefficient ADIS16350 100 ppm/°C

ADIS16355 40 ppm/°C

Axis Nonorthogonality 25°C, difference from 90° ideal ±0.25 Degree

Axis Misalignment 25°C, relative to base-plate and guide pins ±0.5 Degree

Nonlinearity Best fit straight line ±0.2 % of FS

ACCELEROMETER BIAS

In-Run Bias Stability 25°C, 1 σ 0.7 mg

Velocity Random Walk 25°C 2.0 m/s/√hr

Temperature Coefficient ADIS16350 4 mg/°C

ADIS16355 0.5 mg/°C

ACCELEROMETER NOISE PERFORMANCE

Output Noise 25°C, no filtering 35 mg rms

Noise Density 25°C, no filtering 1.85 mg/√Hz rms

ACCELEROMETER FREQUENCY RESPONSE

3 dB Bandwidth 350 Hz

Sensor Resonant Frequency 10 kHz

ACCELEROMETER SELF-TEST STATE

Output Change When Active 73 146 219 LSB

ADIS16355

Rev. PrG | Page 4 of 28

Parameter Conditions Min Typ Max Unit

TEMPERATURE SENSOR

Output at 25°C 0 LSB

Scale Factor 6.88 LSB/°C

ADC INPUT

Resolution 12 Bits

Integral Nonlinearity ±2 LSB

Differential Nonlinearity ±1 LSB

Offset Error ±4 LSB

Gain Error ±2 LSB

Input Range 0 2.5 V

Input Capacitance During acquisition 20 pF

DAC OUTPUT 5 kΩ/100 pF to GND

Resolution 12 Bits

Relative Accuracy For Code 101 to Code 4095 ±4 LSB

Differential Nonlinearity ±1 LSB

Offset Error ±5 mV

Gain Error ±0.5 %

Output Range 0 to 2.5 V

Output Impedance 2 Ω

Output Settling Time 10 µs

LOGIC INPUTS

Input High Voltage, VINH 2.0 V

Input Low Voltage, VINL 0.8 V

For −CS signal when used to wake up from

sleep mode 0.55 V

Logic 1 Input Current, IINH V

IH = 3.3 V ±0.2 ±10 µA

Logic 0 Input Current, IINL V

IL = 0 V

All except RST −40 −60 A

RST −1 mA

Input Capacitance, CIN 10 pF

DIGITAL OUTPUTS

Output High Voltage, VOH I

SOURCE = 1.6 mA 2.4 V

Output Low Voltage, VOL I

SINK = 1.6 mA 0.4 V

SLEEP TIMER

Timeout Period1 0.5 128 Sec

FLASH MEMORY

Endurance2 10,000 Cycles

Data Retention3 T

J = 85C 20 Years

CONVERSION RATE

Maximum Sample Rate SMPL_PRD = 0x01 819.2 SPS

Minimum Sample Rate SPML_PRD = 0xFF 0.413 SPS

START-UP TIME4

Initial Power Up 150 ms

Sleep Mode Recovery 3 ms

POWER SUPPLY

Operating Voltage Range, VCC 4.75 5.0 5.25 V

Power Supply Current Normal mode at 25°C 33 mA

Fast mode at 25°C 57 mA

Sleep mode at 25°C 500 µA

1 Guaranteed by design

2 Endurance is qualified as per JEDEC Standard 22 Method A117 and measured at −40°C, +25°C, +85°C, and +125°C.

3 Retention lifetime equivalent at junction temperature (TJ) 85°C as per JEDEC Standard 22 Method A117. Retention lifetime decreases with junction temperature.

4 This is defined as the time from wake-up to the first conversion. This time does not include sensor settling time, which is dependent on the filter settings

ADIS16355

Rev. PrG | Page 5 of 28

TIMING SPECIFICATIONS

TA = 25°C, Vcc = 5.0 V, angular rate = 0°/s, unless otherwise noted.

Table 2.

Parameter Description Min1 Typ Max1 Unit

fSCLK Fast mode, SMPL_PRD ≤ 0x09 (fS ≥ 164 Hz) 0.01 2 MHz

Normal mode, SMPL_PRD ≥ 0x0A (fS ≤ 149 Hz) 10 300 kHz

tDATARATE Data rate time, fast mode, SMPL_PRD ≤ 0x09 (fS ≥ 164 Hz) 40 s

Data rate time, normal mode, SMPL_PRD ≥ 0x0A (fS ≤ 149 Hz) 160 s

tDATASTALL Data stall time, fast mode SMPL_PRD ≤ 0x09 (fS ≥ 164 Hz) 9 s

Data stall time, normal mode SMPL_PRD ≥ 0x0A (fS ≤ 149 Hz) 75 s

tCS Chip select to clock edge 48.8 ns

tDAV Data output valid after SCLK falling edge2 100 ns

tDSU Data input setup time before SCLK rising edge 24.4 ns

tDHD Data input hold time after SCLK rising edge 48.8 ns

tDF Data output fall time 5 12.5 ns

tDR Data output rise time 5 12.5 ns

tSFS CS high after SCLK edge3 5 ns

1 Guaranteed by design, not production tested.

2 The MSB presents an exception to this parameter. The MSB clocks out on the falling edge of CS. The rest of the DOUT bits are clocked after the falling edge of SCLK and

are governed by this specification.

3 This parameter may need to be expanded to allow for proper capture of the LSB. After CS goes high, the DOUT line goes into a high impedance state.

TIMING DIAGRAMS

SCLK

tDATARATE

tDATASTALL

06522-002

Figure 2. SPI Chip Select Timing

SCLK

DOUT

DIN

1 2 3 4 5 6 15 16

W/R A5 A4 A3 A2 D2

MSB DB14

D1 LSB

DB13 DB12 DB10DB11 DB2 LSBDB1

SFS

DAV

DHD

DSU

06522-003

Figure 3. SPI Timing, Utilizing SPI Settings Typically Identified as Phase = 1, Polarity = 1

ADIS16355

Rev. PrG | Page 6 of 28

ABSOLUTE MAXIMUM RATINGS

Table 3.

Parameter Rating

Acceleration

Any Axis, Unpowered 2000 g

Any Axis, Powered 2000 g

VCC to COM −0.3 V to +6.0 V

Digital Input/Output Voltage to COM −0.3 V to +5.3 V

Analog Inputs to COM −0.3 V to 3.6 V

Operating Temperature Range −40°C to +85°C

Storage Temperature Range −65°C to +125°C1, 2

1 Extended exposure to temperatures outside of the specified temperature

range of −40°C to +85°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 +85°C.

2 Although the device is capable of withstanding short-term exposure to

+150°C, long-term exposure threatens internal mechanical integrity.

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 θJA θ

JC Device Weight

24-Lead Module 39.8°C/W 14.2°C/W 16 grams

ESD CAUTION

ADIS16355

Rev. PrG | Page 7 of 28

PIN CONFIGURATION AND FUNCTION DESCRIPTIONS

PIN 23

PIN 24

FLEX

PIN 1

PIN 2

TOP VIEW

POINT OF PERCUSSION

(WHEN LINEAR ACCELEROMETER

ORIGIN ALIGNMENT ENABLED)

TO HOUSING

06522-004

Figure 4. Pin Configuration, Connector Top View

Table 5. Pin Function Descriptions

Pin No. Mnemonic Type1 Description

1 DNC N/A Do not connect

2 DNC N/A Do not connect

3 SCLK I SPI serial clock

4 DOUT O SPI data output

5 DIN I SPI data input

6 CS I SPI chip select

7 DIO1 I/O Digital input/output

8 RST I Reset

9 DIO2 I/O Digital input/output

10 VCC S Power supply

11 VCC S Power supply

12 VCC S Power supply

13 GND S Power ground

14 GND S Power ground

15 GND S Power ground

16 DNC N/A Do not connect

17 DNC N/A Do not connect

18 DNC N/A Do not connect

19 DNC N/A Do not connect

20 AUX_DAC O Auxiliary, 12-bit, DAC output

21 AUX_ADC I Auxiliary, 12-bit, ADC input

22 DNC N/A Do not connect

23 DNC N/A Do not connect

24 DNC N/A Do not connect

1 S = supply, O = output, I = input.

ADIS16355

Rev. PrG | Page 8 of 28

TYPICAL PERFORMANCE CHARACTERISTICS

–5

–50 100

SENSITIVITY (%)

TEMPERATURE (°C)

06522-030

–1

–2

–3

–4

–35 –20 –5 10 25 40 55 70 85

+1σ

–1σ

Figure 5. ADIS16350 Gyroscope Sensitivity vs. Temperature

–20

–15

BIAS (°/s)

TEMPERATURE (°C)

06522-031

–5

–10

–50 100–35 –20 –5 10 25 40 55 70 85

+1σ

–1σ

Figure 6. ADIS16350 Gyroscope Bias vs. Temperature

1.0

–1.0

SENSITIVITY (%)

TEMPERATURE (°C)

06522-032

0.6

0.4

0.2

0.8

–0.4

–0.2

–0.6

–0.8

–50 100–35 –20 –5 10 25 40 55 70 85

+1σ

–1σ

Figure 7. ADIS16350 Accelerometer Sensitivity vs. Temperature

Gyroscope Sensitivity vs. Temperature

-0.40

-0.30

-0.20

-0.10

0.00

0.10

0.20

0.30

0.40

-50-35-20-5 10 2540 5570 85100

TEMPERATURE (

Sensitivity -

-1

Figure 8. ADIS16355 Gyroscope Sensitivity vs. Temperature

Gyroscope Bias vs. Temperature

-1.00

-0.75

-0.50

-0.25

0.00

0.25

0.50

0.75

1.00

-50-35-20-5 10 2540 5570 85100

TEMPERATURE (

BIAS (deg/sec)

-1

Figure 9. ADIS16350 Gyroscope Bias vs. Temperature

Accelerometer Sensitivity vs. Temperature

-1.00

-0.75

-0.50

-0.25

0.00

0.25

0.50

0.75

1.00

-50 -35 -20 -5 10 25 40 55 70 85 100

TEMPERATURE (

Sensitivity (%

)

-1

Figure 10. ADIS16350 Accelerometer Sensitivity vs. Temperature

ADIS16355

Rev. PrG | Page 9 of 28

200

100

–100

400

300

–400

–50

BIAS (mg)

TEMPERATURE (°C)

06522-033

–300

–200

100–35 –20 –5 10 25 40 55 70 85

+1σ

–1σ

Figure 11. ADIS16350 Accelerometer Bias vs. Temperature

0.1

0.01

0.001

0.01 0.1 1 10 100 1000

ROOT ALLAN VARIANCE (°/s)

INTEGRATION TIME (Seconds)

MEAN

+1σ

–1σ

06522-005

Figure 12. Gyroscope Root Allan Variance

0.1

0.0001

0.01 1000

ROOT ALLAN VARIANCE (g)

INTEGRATION TIME (Seconds)

06522-008

0.1 1 10 100

0.001

0.01

–1

MEAN

Figure 13. Accelerometer Root Allan Variance

Accelerometer Bias vs. Temperature

-60

-40

-20

-50 -35 -20 -5 10 25 40 55 70 85 100

TEMPERATURE (

BIAS (mg)

-1

Figure 14. ADIS16350 Accelerometer Bias vs. Temperature

–0.1 0.40.30.20.10

PERCENTAGE OF POPULATION (%)

SENSITIVITY ERROR (%)

06522-010

Figure 15. Gyroscope Sensitivity Error, +25°C

–0.3 –0.2 0.40.30.20.10–0.1

PERCENTAGE OF POPULATION (%)

BIAS VOLTAGE SENSITIVITY (°/s/V)

06522-011

Figure 16. Gyroscope Bias Voltage Power Supply Sensitivity, +25°C

ADIS16355

Rev. PrG | Page 10 of 28

–0.5 –0.2–0.3–0.4 –0.1 0 0.1 0.3 0.3 0.4 0.5

PERCENTAGE OF POPULATION (%)

SENSITIVITY ERROR (%)

06522-013

Figure 17. Accelerometer Sensitivity Error Distribution, +25°C

–0.10 –0.08 –0.06 –0.04 –0.02 0 0.02 0.04 0.06 0.08 0.10

PERCENTAGE OF POPULATION (%)

(°/s/g)

06522-014

Figure 18. Gyroscope Bias Sensitivity to Linear Acceleration, +25°C

–0.10 –0.08 –0.06 –0.04 –0.02 0 0.02 0.04 0.06 0.08 0.10

PERCENTAGE OF POPULATION (%)

GYROSCOPE AXIS NONORTHOGANALITY (°)

06522-015

Figure 19. Gyroscope Alignment Distribution, +25°C

14.05

13.25

13.35

13.45

13.55

13.65

13.75

13.85

13.95

–360 360270180900–90–180–270

SENSITIVITY (°/s/LSB)

RATE (°/s)

–1

MEAN

6522-006

Figure 20. Gyroscope Linearity

0.5

0.4

0.3

0.2

0.1

–0.1

–0.2

–0.3

–0.4

–0.5

BIAS (°/s)

TIME (Hour:Minute)

06522-017

0.00

0:51

1:43

2:35

3:27

4:19

5:10

6:02

7:07

8:15

9:06

9:58

10:50

11:42

12:33

13:25

14:17

15:09

16:00

16:52

17:44

18:35

19:27

20:19

Figure 21. Long-Term Bias Stability, +25°C

–0.24 –0.16 –0.08 0 0.08 0.16 0.24

PERCENTAGE OF POPULATION (%)

ACCELEROMETER AXIS NONORTHOGANALITY (°)

06522-018

Figure 22. Accelerometer Alignment Distribution, +25°C

Figure 23. Normal Mode Power Supply Current Distribution, +25°C

ADIS16355

Rev. PrG | Page 11 of 28

45 46 47 48 49 50 51 52 53 54 55 56 57 58

PERCENTAGE OF POPULATION (%)

GYROSCOPE POSITIVE SELF-TEST (°/s)

06522-020

Figure 24. Gyroscope Positive Self-Test Distribution, +25°C

–57 –56 –55 –54 –53 –52 –51 –50 –49 –48 –47 –46 –45 –44

PERCENTAGE OF POPULATION (%)

GYROSCOPE NEGATIVE SELF-TEST (°/s)

06522-021

Figure 25 Gyroscope Negative Self-Test Distribution, +25°C

0.30 0.32 0.34 0.36 0.38 0.40 0.42 0.44 0.46 0.48

PERCENTAGE OF POPULATION (%)

ACCELEROMETER SELF-TEST (

)

06522-022

Figure 26. Accelerometer Self-Test Distribution, +25°C

2.722

2.622

2.522

2.422

2.322

–16 1612840–4–8–12

SENSITIVITY (

g/LSB)

ACCELERATION (g)

–1σ

MEAN

+1σ

06522-009

Figure 27. Accelerometer Linearity

ADIS16355

Rev. PrG | Page 12 of 28

THEORY OF OPERATION

OVERVIEW

The ADIS16350 integrates three orthogonal axes of gyroscope

sensors with three orthogonal axes of accelerometer sensors,

creating the basic six degrees of freedom (6DOF) in a single

package. The accelerometers are oriented along the axis of rota-

tion for each gyroscope. These six sensing elements are held

together by a mechanical structure that provides tight force and

motion coupling. Each sensor’s output signal is sampled using

an ADC, and then the digital data is fed into a proprietary digital

processing circuit. The digital processing circuit applies the

correction tables to each sensor’s output, manages the input/

output function using a simple register structure and serial inter-

face, and provides many other features that simplify system-level

designs.

GYROSCOPE SENSOR

The core angular rate sensor (gyroscope) used in the ADIS16350

operates on the principle of a resonator gyroscope. Two poly-

silicon sensing structures each contain a dither frame, which is

electrostatically driven to resonance. This provides the necessary

velocity element to produce a Coriolis force during rotation. At

two of the outer extremes of each frame, orthogonal to the

dither motion, are movable fingers placed between fixed fingers to

form a capacitive pickoff structure that senses Coriolis motion.

The resulting signal is fed to a series of gain and demodulation

stages that produce the electrical rate signal output.

ACCELEROMETER SENSOR

The core acceleration sensor used in the ADIS16350 is a surface

micromachined polysilicon structure built on top of the silicon

wafer. Polysilicon springs suspend the structure over the surface

of the wafer and provide a resistance against acceleration forces.

Deflection of the structure is measured using a differential cap-

acitor that consists of independent fixed plates and central

plates attached to the moving mass. Acceleration deflects the

beam and unbalances the differential capacitor, resulting in a

differential output that is fed to a series of gain and demodu-

lation stages that produce the electrical rate signal output.

FACTORY CALIBRATION

The ADIS16350 provides a factory calibration that simplifies

the process of integrating it into system level designs. This

calibration provides correction for initial sensor bias and

sensitivity, power supply variation, axial alignment, and linear

acceleration (gyroscopes). An extensive, three-dimensional

characterization, provides the basis for generating correction

tables for each individual sensor. The ADIS16355 provides the

same calibration, over temperature.

CONTROL REGISTER STRUCTURE

The ADIS16350 provides configuration control to many critical

operating parameters by using a dual-memory register structure.

The volatile SRAM register locations control operation of the

part while the nonvolatile flash memory locations preserve the

configuration settings. Updating a register’s contents only

affects its SRAM location. Preserving the updates in its corres-

ponding flash memory location requires initiation of the flash

update command. This helps reduce the number of write cycles

to the flash memory and consequently increases the endurance

of the flash memory. During startup and reset-recovery sequen-

ces, the flash memory contents are automatically loaded into

the SRAM register locations.

AUXILIARY ADC FUNCTION

The auxiliary ADC function integrates a standard 12-bit ADC

into the ADIS16350 to digitize other system-level analog

signals. The output of the ADC can be monitored through the

AUX_ADC register, as defined in Table 7. The ADC is a 12-bit

successive approximation converter. The output data is pre-

sented in straight binary format with the full-scale range

extending from 0 V to 2.5 V.

Figure 28 shows the equivalent circuit of the analog input

structure of the ADC. The input capacitor (C1) is typically 4 pF

and can be attributed to parasitic package capacitance. The two

diodes provide ESD protection for the analog input. Care must

be taken to ensure that the analog input signals are never

outside the range of −0.3 V to +3.5 V. This causes the diodes

to become forward-biased and to start conducting. The diodes

can handle 10 mA without causing irreversible damage. The

resistor is a lumped component that represents the on resistance

of the switches. The value of this resistance is typically 100 Ω.

Capacitor C2 represents the ADC sampling capacitor and is

typically 16 pF.

06522-023

Figure 28. Equivalent Analog Input Circuit

Conversion Phase: Switch Open

Track Phase: Switch Closed

For ac applications, removing high frequency components from

the analog input signal is recommended by the use of a low-pass

filter on the analog input pin.

In applications where harmonic distortion and signal-to-noise

ratios are critical, the analog input must be driven from a low

impedance source. Large source impedances significantly affect

the ac performance of the ADC. This can necessitate the use of

an input buffer amplifier. When no input amplifier is used to drive

the analog input, the source impedance should be limited to

values lower than 1 kΩ.

ADIS16355

Rev. PrG | Page 13 of 28

BASIC OPERATION

The ADIS16350 is designed for simple integration into system

designs, requiring only a 5.0 V power supply and a four-wire,

industry standard serial peripheral interface (SPI). All outputs and

user-programmable functions are handled by a simple register

structure. Each register is 16 bits in length and has its own

unique bit map. The 16 bits in each register consist of an upper

byte (D8 to D15) and a lower byte (D0 to D7), each with its own

6-bit address.

SERIAL PERIPHERAL INTERFACE (SPI)

The ADIS16350 serial peripheral interface (SPI) port includes

four signals: chip select (CS), serial clock (SCLK), data input

(DIN), and data output (DOUT). The CS line enables the

ADIS16350 SPI port and frames each SPI event. When this

signal is high, the DOUT line is in a high impedance state and

the signals on DIN and SCLK have no impact on operation. A

complete data frame contains 16 clock cycles. Because the SPI

port operates in full duplex mode, it supports simultaneous,

16-bit receive (DIN) and transmit (DOUT) functions during the

same data frame. This enables one to configure the next read

cycle, while at the same time, receiving the data associated with

the previous configuration.

Refer to Table 2, Figure 2, and Figure 3 for detailed information

regarding timing and operation of the SPI port.

Writing to Registers

Figure 29 displays a typical data frame for writing a command

to a control register. In this case, the first bit of the DIN sequence

is a 1, followed by a 0, the 6-bit address of the target register,

and the 8-bit data command. Because each write command

covers a single byte of data, two data frames are required when

writing the entire 16-bit space of a register.

Reading from Registers

Reading the contents of a register requires a modification to the

sequence illustrated in Figure 29. In this case, the first two bits

in the DIN sequence are 0, followed by the address of the register.

Each register has two addresses (an upper address and a lower

address), but either one can be used to access the entire 16 bits of

data. The final 8 bits of the DIN sequence are irrelevant and can be

counted as “don’t cares” during a read command. During the next

data frame, the DOUT sequence contains the register’s 16-bit

data, as shown in Figure 30. Although a single read command

requires two separate data frames, the full duplex mode

minimizes this overhead, requiring only one extra data frame when

continuously sampling.

SCL

DIN W/R A5 A4 A3 A2 A1 A0 DC7 DC6 DC5 DC4 DC3 DC2 DC1 DC0

DATA FRAME

WRITE = 1

READ = 0

DON’T CARE FOR READ COMMANDS

06522-024

Figure 29. DIN Bit Sequence

ADDRESS DON’T CARE NEXT COMMAND

BASED ON PREVIOUS COMMAND

DATA FRAME

16-BIT REGISTER CONTENTS

SCLK

DIN

DOUT

ZERO

W/R BIT

DATA FRAME

06522-025

Figure 30. SPI Sequence for Read Commands

ADIS16355

Rev. PrG | Page 14 of 28

DATA OUTPUT REGISTER ACCESS

The ADIS16350 provides access to a full 6DOF set of calibrated

motion measurements, power supply measurements, temper-

ature measurements, and an auxiliary 12-bit ADC channel.

This output data is continuously updating internally, regardless

of user read rates. Table 6 describes the structure of all

ADIS16350 output data registers.

Table 6. Output Register Bit Map

MSB LSB

ND EA D13 D12 D11 D10 D9 D8

D7 D6 D5 D4 D3 D2 D1 D0

The MSB holds the new data (ND) indicator. When the output

registers are updated with new data, the ND bit goes to a 1 state.

After the output data is read, it returns to a 0 state. The EA bit

indicates a system error or an alarm condition that can result

from various conditions, such as a power supply out of range

condition. See the Status and Diagnostics section for more

details. The output data is either 12 bits or 14 bits in length. For

the 12-bit output data, Bit D13 and Bit D12 are assigned “don’t-

care” status.

The output data register map is located in Table 7 and provides

all of the necessary details for accessing each register’s data.

Table 8 displays the output coding for the gyroscope output

registers and Table 9 provides output coding for the acceleration

registers. Figure 31 provides an example of an SPI read cycle for

the XGYRO_OUT register.

Table 7. Data Output Register Information

Name Function Addresses

Data

Length Data Format

Scale Factor

(per LSB)

SUPPLY_OUT Power Supply Measurement 0x03, 0x02 12 bits Binary 1.8315 mV

XGYRO_OUT X-axis Gyroscope Output Measurement 0x05, 0x04 14 bits Twos Complement 0.07326 °/s1

YGYRO_OUT Y-axis Gyroscope Output Measurement 0x07, 0x06 14 bits Twos Complement 0.07326 °/s1

ZGYRO_OUT Z-axis Gyroscope Output Measurement 0x09, 0x08 14 bits Twos Complement 0.07326 °/s1

XACCL_OUT X-axis Acceleration Output Measurement 0x0B, 0x0A 14 bits Twos Complement 2.522 mg

YACCL_OUT Y-axis Acceleration Output Measurement 0x0D, 0x0C 14 bits Twos Complement 2.522 mg

ZACCL_OUT Z-axis Acceleration Output Measurement 0x0F, 0x0E 14 bits Twos Complement 2.522 mg

XTEMP_OUT2 X-axis Gyroscope Sensor Temperature Measurement 0x11, 0x10 12 bits Twos Complement 0.1453°C

YTEMP_OUT2 Y-axis Gyroscope Sensor Temperature Measurement 0x13, 0x12 12 bits Twos Complement 0.1453°C

ZTEMP_OUT2 Z-axis Gyroscope Sensor Temperature Measurement 0x15, 0x14 12 bits Twos Complement 0.1453°C

AUX_ADC Auxiliary Analog Input Data 0x17, 0x16 12 bits Binary 0.6105 mV

1 Assumes that the scaling is set to 300°/s.

2 Typical condition, 25°C = 0 LSB

Table 8. Output Coding Example, XGYRO_OUT, YGYRO_OUT, and ZGYRO_OUT1, 2

Rate of Rotation

±300°/s Range ±150°/s Range ±75°/s Range Binary Output Hex Output Decimal

80°/s 40°/s 20°/s 00 0100 0100 0100 0x0444 1092

40°/s 20°/s 10°/s 00 0010 0010 0010 0x0222 546

0.07326°/s 0.03663°/s 0.018315°/s 00 0000 0000 0001 0x0001 1

0°/s 0°/s 0°/s 00 0000 0000 0000 0x0000 0

−0.07326°/s −0.03663°/s −0.018315°/s 11 1111 1111 1111 0x3FFF −1

−40°/s −20°/s −10°/s 11 1101 1101 1110 0x3DDE −546

−80°/s −40°/s −20°/s 11 1011 1011 1100 0x3BBC −1092

1 Two MSBs have been masked off and are not considered in the coding.

2 Zero offset null performance are assumed.

ADIS16355

Rev. PrG | Page 15 of 28

Table 9. Output Coding Example, XACCL_OUT, YACCL_OUT, and ZACCL_OUT1, 2

Acceleration (g) Binary Output Hexadecimal Output Decimal

2.522 00 0011 1110 1000 0x03E8 1000

1 00 0001 1000 1101 0x018D 397

0.002522 00 0000 0000 0001 0x0001 1

0 00 0000 0000 0000 0x0000 0

−0.002522 11 1111 1111 1111 0x3FFF −1

−1 11 1110 0111 0011 0x3E73 −397

−2.522 11 1100 0001 1000 0x3C18 −1000

1 Two MSBs have been masked off and are not considered in the coding.

2 Zero offset null performance are assumed.

6522-026

SCLK

DIN

W/R BIT = 0 ADDRESS = 000101

DOUT

DATA = 1011 1101 1101 1110

NEW DATA, NO ALARM, XGYRO_OUT = –40°/s

NOTE: ±300°/s DYNAMIC RANGE SETTING

Figure 31. Example Read Cycle

ADIS16355

Rev. PrG | Page 16 of 28

PROGRAMMING AND CONTROL

CONTROL REGISTER OVERVIEW

The ADIS16350 offers many programmable features controlled

by writing commands to the appropriate control registers using the

SPI. The following sections describe these controls and specify

each function, along with the corresponding register config-

uration. The features available for configuration in this register

space are:

• Calibration

• Global commands

• Operational control

• Sample rate

• Power management

• Digital filtering

• Dynamic range

• DAC output

• Digital input/output

• Operational status and diagnostics

• Self test

• Status conditions

• Alarms

CONTROL REGISTER STRUCTURE

The ADIS16350 uses a temporary, RAM-based memory

structure to facilitate the control registers displayed in Table 10.

The operational configuration is stored in a flash memory

structure that automatically loads into the control registers

during the start-up sequence. Each nonvolatile register has a

corresponding flash memory location for storing the latest

configuration contents. The contents of each nonvolatile reg-

ister must be stored to flash manually.

Note that the contents of the control register are only nonvolatile

when they are stored to flash. The flash update command, made

available in the COMMAND register, provides this function.

The endurance register provides a counter, which allows for

reliability management against the flash memory’s write cycle

specification.

Table 10. Control Register Mapping

ENDURANCE R Nonvolatile 0x00, 0x01 2 Flash memory write count Table 30

0x02 to 0x17 22 Output data Table 7

0x18, 0x019 2 Reserved

XGYRO_OFF R/W Nonvolatile 0x1A, 0x1B 2 X-axis gyroscope bias offset factor Table 11, Table 12

YGYRO_OFF R/W Nonvolatile 0x1C, 0x1D 2 Y-axis gyroscope bias offset factor Table 11, Table 12

ZGYRO_OFF R/W Nonvolatile 0x1E, 0x1F 2 Z-axis gyroscope bias offset factor Table 11, Table 12

XACCL_OFF R/W Nonvolatile 0x20, 0x21 2 X-axis acceleration bias offset factor Table 13, Table 14

YACCL_OFF R/W Nonvolatile 0x22, 0x23 2 Y-axis acceleration bias offset factor Table 13, Table 14

ZACCL_OFF R/W Nonvolatile 0x24, 0x25 2 Z-axis acceleration bias offset factor Table 13, Table 14

ALM_MAG1 R/W Nonvolatile 0x26, 0X27 2 Alarm 1 amplitude threshold Table 33, Table 34

ALM_MAG2 R/W Nonvolatile 0x28, 0x29 2 Alarm 2 amplitude threshold Table 33, Table 34

ALM_SMPL1 R/W Nonvolatile 0x2A, 0x2B 2 Alarm 1 sample period Table 35, Table 36

ALM_SMPL2 R/W Nonvolatile 0x2C, 0x2D 2 Alarm 2 sample period Table 35, Table 36

ALM_CTRL R/W Nonvolatile 0x2E, 0x2F 2 Alarm control Table 37, Table 38

AUX_DAC R/W Volatile 0x30, 0x31 2 Auxiliary DAC data Table 23, Table 24

GPIO_CTRL R/W Volatile 0x32, 0x33 2 Auxiliary digital input/output control Table 25, Table 26

MSC_CTRL R/W Nonvolatile1 0x34, 0x35 2 Miscellaneous control Table 28, Table 29

SMPL_PRD R/W Nonvolatile 0x36, 0x37 2 Internal sample period (rate) control Table 17, Table 18

SENS/AVG R/W Nonvolatile 0x38, 0x39 2 Dynamic range/digital filter control Table 21, Table 22

SLP_CNT R/W Volatile 0x3A, 0x3B 2 Sleep mode control Table 19, Table 20

STATUS R Volatile 0x3C, 0x3D 2 System status Table 31, Table 32

COMMAND W N/A 0x3E, 0x3F 2 System command Table 15, Table 16

1 The contents of the lower byte are nonvolatile; the contents of the lower byte are volatile.

ADIS16355

Rev. PrG | Page 17 of 28

CALIBRATION

For applications that require point of use calibration, the

ADIS16350 provides bias correction registers for all six sensors.

Table 11, Table 12, Table 13, and Table 14 provide the details

required for using these registers to calibrate the ADIS16350

sensors.

Table 11. Gyroscope Bias Correction Registers

XGYRO_OFF 0x1B, 0x1A Default value = 0x0000

YGYRO_OFF 0x1D, 0x1C Scale = 0.018315°/s per LSB

ZGYRO_OFF 0x1F, 0x1E Twos complement, read/write

Table 12. Gyroscope Bias Correction Register Bits

Bits Description

[15:13] Not used

[12:0] Data bits, typical adjustment range = ±75°

Table 13. Accelerometer Bias Correction Registers

XACCL_OFF 0x21, 0x20 Default value = 0x0000

YACCL_OFF 0x23, 0x22 Scale = 2.522 mg per LSB

ZACCL_OFF 0x25, 0x24 Twos complement, read/write

Table 14. Accelerometer Bias Correction Register Bits

Bits Description

[15:12] Not used

[11:0] Data bits, typical adjustment range = ±5.16 g

Manual Bias Calibration

Since each offset bias register has read/write access, the bias of

each sensor is adjustable. For example, if an output offset of

0.18 °/s is observed in the Z-axis gyroscope, the ZGYRO_OFF

accuracy. Using its sensitivity of 0.018315°/s, an adjustment of

−10 LSBs is required. The twos complement, hexadecimal code

of −10 LSBs is 0x1FF6.

To implement this calibration factor, use the following

pseudo code:

Write 0xF6 to Address 0x1E, then write 0x1F to

Address 0x1F

This step reduces the 0.18°/s error to 0.00315°/s.

Automatic Bias Null Calibration

The ADIS16350 provides a single-command, automatic bias

calibration for all three-gyroscope sensors. The COMMAND

gyroscope output registers, then loads the three bias correction

registers with values that return their outputs to zero (null). A

single register write command starts this process (see Table 16).

Write 0x01 to Address 0x3E

Precision Automatic Bias Null Calibration

The ADIS16350 also provides a single-command function that

incorporates the optimal averaging time for generating the

appropriate bias correction factors for all three gyroscope sen-

sors. This command requires approximately 30 seconds. For

optimal calibration accuracy, the device should be stable (no

motion) for this entire period. Once it has started, a reset

command is required to stop it prematurely, if required. The

following sequence starts this calibration option (See Table 16):

Write 0x10 to Address 0x3E

Restoring Factory Calibration

The ADIS16350 factory calibration can be restored by returning

the contents of each bias correction register to their default

value of zero. This command also flushes all of the data from

the digital filter taps. To accomplish this function for all six-

sensor signal paths (see Table 16):

Write 0x02 to Address 0x3E

Linear Acceleration Bias Compensation (Gyroscopes)

The ADIS16350 provides compensation for acceleration

influences on the gyroscopes’ bias behavior, using the

MSC_CTRL register.

Set Bit 7 of Address 0x34 to 1 (see Table 29)

Linear Acceleration Origin Alignment

The ADIS16350 provides origin alignment for the accelero-

meters, to the point of percussion (see Figure 4), using the

MSC_CTRL register.

Set Bit 6 of Address 0x34 to a 1 (see Table 29)

GLOBAL COMMANDS

The ADIS16350 provides global commands for common

operations such as calibration, flash update, auxiliary DAC

latch, and software reset. Each of these global commands has a

unique control bit assigned to it in the COMMAND register and

is initiated by writing a 1 to its assigned bit.

The flash update command writes the contents of each non-

volatile register into flash memory for storage. This process

takes approximately 100 ms and requires the power supply

voltage to be within specification for the duration of the event.

Note that this operation also automatically follows the auto null,

precision auto null, and factory reset commands. After waiting

the appropriate time for the flash update to complete, verify

successful completion by reading the STATUS register (flash

update error = zero, if successful).

The DAC latch command loads the contents of AUX_DAC into

the DAC latches. Since the AUX_DAC contents must be updated

one byte at a time, this command ensures a stable DAC output

voltage during updates. Finally, the software reset command

sends the ADIS16350 digital processor into a restart sequence,

effectively accomplishing the same tasks as the RST line.

ADIS16355

Rev. PrG | Page 18 of 28

Table 15. COMMAND Register Definition

Address Default Format Access

0x3F, 0x3E N/A N/A Write only

Table 16. COMMAND Bit Descriptions

Bits Description

[15:8] Not used

[7] Software reset command

[6:5] Not used

[4] Precision auto null command

[3] Flash update command

[2] Auxiliary DAC data latch

[1] Factory calibration restore command

[0] Auto null command

OPERATIONAL CONTROL

Internal Sample Rate

The internal sample rate defines how often data output variables

are updated, independent of the rate at which they are read out

on the SPI port. The SMPL_PRD register controls the ADIS16350

internal sample rate and has two parts: a time base and a multi-

plier. The sample period can be calculated using the following

equation:

TS = TB × (NS + 1)

where:

TS is the sample period.

TB is the time base.

NS is the multiplier.

The default value is the minimum register setting, 0x01, which

corresponds to the maximum sample rate of 819.2 samples per

second. The contents of this register are nonvolatile.

Table 17. SMPL_PRD Register Definition

Address Default Format Access

0x37, 0x36 0x0001 N/A R/W

Table 18. SMPL_PRD Bit Descriptions

Bits Description

[15:8] Not used

[7] Time base, 0 = 0.61035 ms, 1 = 18.921 ms

[6:0] Multiplier (add 1 before multiplying by the time base)

An example calculation of the sample period for the device is

If SMPL_PRD = 0x0007, Bits[7:0] = 00000111

Bit 7 = 0 → TB = 0.61035 ms

Bits[6:0] = 000000111 = 7 = NS

TS = TB × (NS + 1) = = 0.61035 ms × (7 + 1) = 4.8828 ms

fS = 1∕TS = 204.8 SPS

The sample rate setting has a direct impact on the SPI data rate

capability. For SMPL_PRD settings less than, or equal to 0x09

(fast mode), the SPI SCLK can run at a rate up to 2.0 MHz. For

SMPL_PRD settings greater than 0x09 (normal mode), the SPI

SCLK can run at a rate up to 300 kHz.

The sample rate setting also affects the power dissipation.

The normal mode power dissipation is approximately 67% less

than the fast mode power dissipation. The two different modes

of operation offer a system-level trade-off between performance

(sample rate, serial transfer rate) and power dissipation.

Power Management

In addition to offering two different performance modes for

power optimization, the ADIS16350 offers a programmable

shutdown period. Writing the appropriate sleep time to the

SLP_CNT register shuts the device down for the specified time.

The following example illustrates this relationship:

Bits[7:0] = 00000110 = 6 codes = 3 seconds

After completing the sleep period, the ADIS16350 returns to

normal operation. If measurements are required before sleep

period completion, the ADIS16350 can be awakened by pulling

the CS line to down to a 0 state, then returning it back to a 1

state. Otherwise, the CS line must be kept in a 1 (high) state to

maintain sleep mode.

When writing a sleep time to the SLP_CNT register, the time

between the 16th SCLK edge and the CS rising edge must be less

than 10 μs in fast mode and 80 μs on normal mode.

Table 19. SLP_CNT Register Definition

Address Scale1 Default Format Access

0x3B, 0x3A 0.5 sec 0x0000 Binary R/W

1 Scale is the weight of each LSB.

Table 20. SLP_CNT Bit Descriptions

Bits Description

[15:8] Not used

[7:0] Data bits

Digital Filtering

Each sensor’s signal conditioning circuit has an analog bandwidth

of approximately 350 Hz. The ADIS16350 provides a Bartlett

Window FIR filter for additional noise reduction on all of the

output data registers. The SENS/AVG register stores the number

of taps in this filter in seven, power-of-two step sizes (that is,

N = 2M = 1, 2, 4, 16, 32, and 64).

Filter setup requires one simple step: write the appropriate M

factor to the assigned bits in the SENS/AVG register. The bit

assignments are listed in Table 22. The frequency response

relationship for this filter is:

(

)

()

BtfN

tfN

fHfHfH ××π×

××π

== sin

sin

)()()( 2

ADIS16355

Rev. PrG | Page 19 of 28

–20

–40

–60

–80

–100

–120

–140

0.001 0.01 0.1 1

MAGNITUDE (dB)

FREQUENCY (

)

N = 2

N = 4

N = 16

N = 64

06522-027

Figure 32. Bartlett Window FIR Frequency Response

Dynamic Range

The ADIS16350 provides three dynamic range settings: ±75°/s,

±150°/s, and ±300°/s. The lower dynamic range settings (75, 150)

limit the minimum filter tap sizes in order to maintain the resol-

ution as the measurement range decreases. The recommended

order for programming the SENS/AVG register is upper byte

(sensitivity) followed by lower byte (filtering). The contents of the

SENS/AVG register are nonvolatile.

Table 21. SENS/AVG Register Definition

Address Default Format Access

0x39, 0x38 0x0402 N/A R/W

Table 22. SENS/AVG Bit Descriptions

Bits Value Description

[15:11] Not used

[10:8] Measurement range (sensitivity) selection

100 300°/s (default condition)

010 150°/s, filter taps ≥ 4 (Bit 2:0 ≥ 0x02)

001 75°/s, filter taps ≥16 (Bit 2:0 ≥ 0x04)

[7:3] Not used

[2:0] Filter tap setting, M = decimal of these bits

(number of taps, N = 2M)

Auxiliary DAC

The auxiliary DAC provides a 12-bit level adjustment function.

The AUX_DAC register controls the operation of this feature. It

offers a rail-to-rail buffered output that has a range of 0 V to 2.5 V.

The DAC can drive its output to within 5 mV of the ground

reference when it is not sinking current. As the output

approaches ground, the linearity begins to degrade (100 LSB

beginning point). As the sink current increases, the nonlinear

range increases. The DAC output latch function, contained in

the COMMAND register, provides continuous operation while

writing each byte of this register. The contents of this register

are volatile, which means that the desired output level must be

set after every reset and power cycle event.

Table 23. AUX_DAC Register Definition

Address Default Format Access

0x31, 0x30 0x0000 Binary R/W

Table 24. AUX_DAC Bit Descriptions

Bits Description

[15:12] Not used

[11:0] Data bits

0x0000 – 0 V output, 0x0FFF – 2.5 V output

General-Purpose Input/Output

The ADIS16350 provides two general-purpose pins that enable

digital input/output control using the SPI. The GPIO_CTRL

control register establishes the configuration of these pins and

handles the SPI-to-pin controls. Each pin provides the flex-

ibility of both input (read) and output (write) operations.

The contents of this register are volatile. For example, writing a

0x0202 to this register establishes Line 2 as an output and sets

its level as a 1. Writing 0x0000 to this register establishes both

lines as inputs, and their status can be read through Bit 8 and Bit 9

of this register.

The digital input/output lines are also available for data-ready and

alarm/error indications. In the event of conflict, the following

priority structure governs the digital input/output configuration:

1. MSC_CTRL

2. ALM_CTRL

3. GPIO_CTRL

Table 25. GPIO_CTRL Register Definition

Address Default Format Access

0x33, 0x32 0x0000 N/A R/W

Table 26. GPIO_CTRL Bit Descriptions

Bits Description

[15:10] Not used

[9] General-purpose input/output line 2 data level

1 = high, 0 = low

[8] General-purpose input/output line 1 data level

1 = high, 0 = low

[7:2] Not used

[1] General-purpose input/output line 2, data direction

control

1 = output, 0 = input

[0] General-purpose input/output line 1, data direction

control

1 = output, 0 = input

ADIS16355

Rev. PrG | Page 20 of 28

STATUS AND DIAGNOSTICS

The ADIS16350 provides a number of status and diagnostic

functions. Table 27 provides a summary of these functions,

along with their appropriate control registers.

Table 27. Status and Diagnostic Functions

Function Register

Data-ready input/output indicator MSC_CTRL

Self-test, mechanical check for sensor element MSC_CTRL

Status: Check for predefined error conditions STATUS

Flash memory endurance ENDURANCE

Alarms: Configure and check for user-specific

conditions

ALM_MAG1

ALM_MAG2

ALM_SMPL1

ALM_SMPL2

ALM_CTRL

Data-Ready Input/Output Indicator

The data-ready function provides an indication of updated

output data. The MSC_CTRL register provides the opportunity

to configure either of the general-purpose input/output pins (DIO1

and DIO2) as a data-ready indicator signal.

Table 28. MSC_CTRL Register Definition

Address Default Format Access

0x35, 0x34 0x0000 N/A R/W

Table 29. MSC_CTRL Bit Descriptions

Bits Description

[15:11] Not used

[10] Internal self-test enable (clears on completion)

1 = enabled, 0 = disabled

[9] Manual self-test, negative stimulus

1 = enabled, 0 = disabled

[8] Manual self-test, positive stimulus

1 = enabled, 0 = disabled

[7] Linear acceleration bias compensation for gyroscopes

1 = enabled, 0 = disabled

[6] Linear accelerometer origin alignment

1 = enabled, 0 = disabled

[5:3] Not used

[2] Data-ready enable

1 = enabled, 0 = disabled

[1] Data-ready polarity

1 = active high, 0 = active low

[0] Data-ready line select

1 = DIO2, 0 = DIO1

Self Test

The MSC_CTRL register also provides a self-test function,

which verifies the MEMS sensor’s mechanical integrity. There

are two different self-test options: (1) internal self-test and (2)

external self-test.

The internal test provides a simple, two-step process for

checking the MEMS sensor:.

1. Start the process by writing a 1 to Bit 10 in the MSC_CTRL

2. Check the result by reading Bit 5 of the STATUS register.

If a failure is indicated, then Bit 10 to Bit 15 of the STATUS

The entire cycle takes approximately 35 ms and the output data

is not available during this time. The external self-test is a static

condition that can be enabled and disabled. In this test, both

positive and negative gyroscope MEMS sensor movements are

available. For the accelerometers, only positive MEMS sensor

movement is available.

After writing to the appropriate control bit, the output registers

reflect the changes after a delay that reflects the response time

associated with the sensor/signal conditioning circuit. For

example, the standard 350 Hz bandwidth reflects an expon-

ential response with a time constant of 0.45 ms. Note that the

digital filtering impacts this delay as well. The appropriate bit

definitions for self-test are listed in Table 28 and Table 29.

Flash Memory Endurance

The ENDURANCE register maintains a running count of writes

to the flash memory. It provides up to 32,768 counts. Note that

if this count is exceeded, the register wraps around, and goes

back to zero, before beginning to increment again.

Table 30. ENDURANCE Register Definition

Address Default Format Access

0x01, 0x00 N/A Binary Read only

ADIS16355

Rev. PrG | Page 21 of 28

Status Conditions

The STATUS register contains the following error condition

flags: alarm conditions, self-test status, overrange, SPI commun-

ication failure, control register update failure, and power supply

out of range. See Table 31 and Table 32 for the appropriate

The bits assigned for checking power supply range and sensor

overrange automatically reset to zero when the error condition

no longer exists. The remaining error flag bits in the STATUS

a STATUS register read clears all of the bits to zero. If any error

conditions remain, the bits revert to 1 during the next internal

output register update cycle.

Table 31. STATUS Register Definition

Address Default Format Access

0x3D, 0x3C 0x0000 N/A Read only

Table 32. STATUS Bit Descriptions

Bits Description

[15] Z-axis accelerometer self diagnostic error flag

1 = failure, 0 = passing

[14] Y-axis accelerometer self diagnostic error flag

1 = failure, 0 = passing

[13] X-axis accelerometer self diagnostic error flag

1 = failure, 0 = passing

[12] Z-axis gyroscope self diagnostic error flag

1 = failure, 0 = passing

[11] Y-axis gyroscope self diagnostic error flag

1 = failure, 0 = passing

[10] X-axis gyroscope self diagnostic error flag

1 = failure, 0 = passing

[9] Alarm 2 status

1 = active, 0 = inactive

[8] Alarm 1 status

1 = active, 0 = inactive

[7:6] Not used

[5] Self-test diagnostic error flag

1 = error condition, 0 = normal operation

[4] Sensor over range (any of the six)

1 = error condition, 0 = normal operation

[3] SPI communications failure

1 = error condition, 0 = normal operation

[2] Control register update failed

1 = error condition, 0 = normal operation

[1] Power supply in range above 5.25 V

1 = above 5.25 V, 0 = below 5.25 V (normal)

[0] Power supply below 4.75 V

1 = below 4.75 V, 0 = above 4.75 V (normal)

Alarms

The ADIS16350 provides two independent alarm options for

event detection. Event detections occur when output register

data meets the configured conditions. Configuration options are:

• All output data registers are available for monitoring as the

source data.

• The source data can be filtered or unfiltered.

• Comparisons can be static or dynamic (rate of change).

• The threshold levels and times are configurable.

• Comparison can be greater than or less than.

The ALM_MAG1 register and the ALM_MAG2 register both

establish the threshold level for detecting events. These registers

take on the format of the source data and provide a bit for

establishing the greater than/less than comparison direction.

When making dynamic comparisons, the ALM_SMPL1 register

and the ALM_SMPL2 register establish the number of averages

taken for the source data as a reference for comparison. In this

configuration, each subsequent source data sample is subtracted

from the previous one, establishing an instantaneous delta. The

ALM_CTRL register controls the source data selection, static/

dynamic selection, filtering selection, and digital input/output

usage for the alarms.

The rate of change calculation is

ettings /2 ALM_MAG1 toaccording with

comparing by determined is alarm change of Rate

)()1(

1DS

1 n

sMY

nyny

C∑

−+=

where:

NDS is the number of samples in ALM_SMPL1 and

ALM_SMPL2.

y(n) is the sampled output data.

MC is the magnitude for comparison in ALM_MAG1 and

ALM_MAG2.

YC is the factor to compare with MC.

ADIS16355

Rev. PrG | Page 22 of 28

Table 33. ALM_MAG1 and ALM_MAG2 Register Definitions

ALM_MAG1 0x27, 0x26 0x0000 N/A R/W

ALM_MAG2 0x29, 0x28 0x0000 N/A R/W

Table 34. ALM_MAG1 and ALM_MAG2 Bit Designations

Bits Description

[15] Comparison polarity: 1 = greater than, 0 = less than

[14] Not used

[13:0] Data bits, format matches source data format

Table 35. ALM_SMPL1 and ALM_SIMPL2 Register Definitions

Registers Addresses Default Format Access

ALM_SMPL1 0x2B, 0x2A 0x0000 Binary R/W

ALM_SMPL2 0x2D, 0x2C 0x0000 Binary R/W

Table 36. ALM_SMPL1 and ALM_SIMPL2 Bit Designations

Bit Description

[15:8] Not used

[7:0] Data bits

Table 37. ALM_CTRL Register Definition

Addresses Default Format Access

0x2F, 0x2E 0x0000 N/A R/W

Table 38. ALM_CTRL Bit Designations

Bits Value Description

[15:12] Alarm 2 source selection

0000 Disable

0001 Power supply output

0010 X-axis gyroscope output

0011 Y-axis gyroscope output

0100 Z-axis gyroscope output

0101 X-axis accelerometer output

0110 Y-axis accelerometer output

0111 Z-axis accelerometer output

1000 X-axis gyroscope temperature output

1001 Y-axis gyroscope temperature output

1010 Z-axis gyroscope temperature output

1011 Auxiliary ADC output

[11:8] Alarm 1 source selection (same as Alarm 2)

[7] Rate of change (ROC) enable for Alarm 2

1 = rate of change, 0 = static level

[6] Rate of change (ROC) enable for Alarm 1

1 = rate of change, 0 = static level

[5] Not used

[4] Comparison data filter setting

1 = filtered data, 0 = unfiltered data

[3] Not used

[2] Alarm output enable

1 = enabled, 0 = disabled

[1] Alarm output polarity

1 = active high, 0 = active low

[0] Alarm output line select

1 = DIO2, 0 = DIO1

ADIS16355

Rev. PrG | Page 23 of 28

APPLICATIONS INFORMATION

INSTALLATION GUIDELINES

Installing the ADIS16350 requires two steps: mechanical

attachment of the body followed by the electrical connection.

This device is designed for post-solder reflow installation. It is

not designed to survive the temperatures associated with

normal solder reflow processes.

Mechanical Attachment

The ADIS16350 is designed for simple mechanical attachment.

The open mounting tabs on each side of the body provide

enough room for 2 mm (or 2-56) machine screws. Note that

316 stainless steel and aluminum screws are available for use

in this attachment.

When planning the installation process, the primary tradeoff to

consider is the attachment strength advantage of stainless steel

against the nonmagnetic properties of aluminum for systems

that employ magnetic sensors. In addition, the ADIS16350

provides 1.5 mm alignment pinholes, one on each side.

Location accuracy of the mating holes may force the use of

a smaller pin. Figure 33 provides a graphical display of the

mechanical attachment and Figure 34 provides a recommend-

ation for the physical layout of all the holes required for

attaching the ADIS16350.

Electrical Connections

The electrical interface for the ADIS16350 is a single connector,

which is attached to a flexible circuit extension, and strengthen-

ed by a rigid 0.7 mm thick PCB (FR4 equivalent material).

This connector is a dual-row, 2-12, 1 mm male header, which

mates to Samtec part number CLM-112-02-L-D-A or the

equivalent. The flexible circuit has stress relief points to absorb

environmental stresses, such as temperature cycling and vibra-

tion. Figure 34 provides the alignment hole locations for designs

that employ the suggested connector mate. This connection is

held by friction only.

Proper Removal

The flexible circuit interface can tear under excessive force

conditions. An example of excessive force is attempting to

break the electrical connection by pulling on the ADIS16350’s

body, placing all of the stress on the flexible circuit.

The electrical connector must be broken by an appropriate tool,

which is designed to apply even pressure to each side of the

rigid part of the flex cable. The recommended extraction

sequence is to break the mate between the electrical interface,

and then to remove the mechanical attachment hardware.

1.588mm HOLE AND SLOT

FOR ALIGNMENT PINS, 2 EACH

DRILL AND TAP HOLE

FOR 2mm (2-56) SCREW,

2 EACH

06522-028

Figure 33. Mechanical Attachment

ADIS16355

Rev. PrG | Page 24 of 28

06522-029

DRILL AND INSERT

1.5mm PIN 2×

(HOLE PLACEMEN

INACCURACY MAY

REQUIRE USE OF

UNDERSIZED PIN).

DRILL AND TAP FOR

M2 SCREW

AS REQUIRED

2×.

BSC

26.700

BSC

0.500 BSC

2×

BSC

27.700

BSC

8.350

16.810

2×

HOLE 2×.

SEE SAMTEC MOUNTING

DRAWING FOR CLM SERIES SOCKET.

THE LOCATION OF THE MATING CONNECTOR

RELATIVE TO THE ALIGNMENT PINS MAY BE

PLACED ±0.75mm FROM THIS DIMENSION AS

DESIRED. PLACING THIS FURTHER OUT WILL

HAVE LESS BEND/STRESS RELIEF IN THE FLEX.

Figure 34. Hole Locations

ADIS16355

Rev. PrG | Page 25 of 28

OUTLINE DIMENSIONS

081507-B

TOP VIEW BOTTOM VIEW

FRONT VIEW

DETAIL A

SIDE VIEW

22.964

22.710

22.456

14.950

14.550

14.150

21.410

21.210

21.010

23.504

23.250

22.996

5.20

5.00

4.80

(2×)

4.20

4.00

3.80

(2×)

17.41

17.21

17.01

(2×)

2.660

2.500

2.340

23.454

23.200

22.946

31.900

31.700

31.500

4.330

BSC

1.588

BSC

2.382

BSC

PIN 24

PIN 1

9.464

9.210

8.956

(2×)

DETAIL A

14.00 BSC

0.305

BSC (24×) 1.00

BSC (22×)

1.65 BSC

5.30

5.00

4.70

7.18

BSC

1.588

BSC

12.10

BSC

0.05

BSC

1.00

BSC

2.00 BSC

10.50

BSC

10.60

BSC

Figure 35. ADIS16350 Module with Connector Interface

(ML-24-2)

Dimensions shown in millimeters

ORDERING GUIDE

Model Temperature Range Package Description Package Option

ADIS16350AMLZ1 −40°C to +85°C 24-Lead Module with Connector Interface ML-24-2

ADIS16350/PCBZ1 Interface Board

ADIS16350/EVALZ1 PC Evaluation System

ADIS16355AMLZ1 −40°C to +85°C 24-Lead Module with Connector Interface ML-24-2

ADIS16355/PCBZ1 Interface Board

ADIS16355/EVALZ1 PC Evaluation System

1 Z = RoHS Compliant Part.

ADIS16355

Rev. PrG | Page 26 of 28

NOTES

ADIS16355

Rev. PrG | Page 27 of 28

NOTES

ADIS16355

Rev. PrG | Page 28 of 28

NOTES

registered trademarks are the property of their respective owners.

PR06874-0-10/07(PrG)