Datasheet ADIS16488A (Analog Devices)
| Manufacturer | Analog Devices |
| Description | Tactical Grade, Ten Degrees of Freedom Inertial Sensor |
| Pages / Page | 3 / 1 — Tactical Grade,. Ten Degrees of Freedom Inertial Sensor. Silicon Anomaly. … |
| File Format / Size | PDF / 91 Kb |
| Document Language | English |
Tactical Grade,. Ten Degrees of Freedom Inertial Sensor. Silicon Anomaly. ADIS16488A. PERFORMANCE ISSUES
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Tactical Grade, Ten Degrees of Freedom Inertial Sensor Silicon Anomaly ADIS16488A
This anomaly list describes the known bugs, anomalies, and workarounds for the ADIS16488A. Analog Devices, Inc., is committed, through future silicon revisions, to continuously improve silicon functionality. Analog Devices tries to ensure that these future silicon revisions remain compatible with your present software/systems by implementing the recommended workarounds outlined within this document.
PERFORMANCE ISSUES Table 1. Error in Soft Iron Correction Factors [er001] Background
The signal chain for the tri-axis magnetometer in the ADIS16488A includes a user-configurable, 3 × 3 soft iron correction matrix. Users configure each value in the soft iron correction matrix by writing to its corresponding register. For example, the SOFT_IRON_S12 register contains the value for correction factor S12. In these registers, 1 LSB = 100/215.
Issue
On units that have firmware Revision 1.07 (or earlier), 1 LSB = 12.5/215, which is eight times lower than the correct value, on the following registers: SOFT_IRON_S12, SOFT_IRON_S13, SOFT_IRON_S21, SOFT_IRON_S31, and SOFT_IRON_S32.
Workaround
Read FIRM_REV to determine the firmware revision of a unit. If FIRM_REV < 0x0108, clear all soft iron correction values (write 0x0000 to each SOFT_IRON_Sxy register) and perform the soft iron correction outside of the ADIS16488A.
Related Issues
None.
Table 2. User Offset Addition Error [er002] Background
The ADIS16488A provides user-configurable bias correction values for each gyroscope and accelerometer(x, y, and z), through the fol owing registers: XG_BIAS_HIGH, XG_BIAS_LOW, YG_BIAS_HIGH, YG_BIAS_LOW, ZG_BIAS_HIGH, ZG_BIAS_LOW, XA_BIAS_HIGH, XA_BIAS_LOW, YA_BIAS_HIGH, YA_BIAS_LOW, ZA_BIAS_HIGH, and ZA_BIAS_LOW.
Issue
On units that have firmware Revision 1.07 (or earlier), there is a computation error that results in a small error in the bias of each sensor (for example, less than 0.02°/sec for the gyroscopes).
Workaround
Read FIRM_REV to determine the firmware revision of a unit. If FIRM_REV < 0x0108, write 0x0000 to XG_BIAS_HIGH, XG_BIAS_LOW, YG_BIAS_HIGH, YG_BIAS_LOW, ZG_BIAS_HIGH, ZG_BIAS_LOW, XA_BIAS_HIGH, XA_BIAS_LOW, YA_BIAS_HIGH, YA_BIAS_LOW, ZA_BIAS_HIGH, and ZA_BIAS_LOW. Apply the bias correction factors to the gyroscope and accelerometer signals outside of the ADIS16488A.
Related Issues
None.
Table 3. Temperature Compensation Error [er003] Background
The ADIS16488A leverages internal temperature sensors as control inputs for the compensation of gyroscope and accelerometer measurements.
Issue
On units that have firmware Revision 1.08 (or earlier), one of the three temperature sensors can be corrupted when using an external clock to drive the sampling. The external clock causes elevated levels of sensitivity to variation in temperature.
Workaround
Read FIRM_REV to determine the firmware revision of a unit. If FIRM_REV < 0x0109, use the internal sample clock if the best temperature sensitivity is necessary.
Related Issues
None.
Table 4. Real-Time Clock (RTC) Functional Issues [er004] Background
The ADIS16488A provides a RTC function that keeps track of time (seconds, minutes, hours, days, months, and years) while the main processor function is not operating (sleep, powered off).
Issue
On units that have firmware Revision 1.08 (or earlier), the days information in TIME_DH_OUT can experience an overflow condition when the device recovers from sleep mode.
Workaround
Read FIRM_REV to determine the firmware revision of a unit. If FIRM_REV < 0x0109, do not use sleep mode if the RTC function is critical for the application.
Related Issues
None.
Rev. 0 Document Feedback 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 One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Tel: 781.329.4700 ©2017 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. Technical Support www.analog.com
Document Outline PERFORMANCE ISSUES ANOMALY STATUS
This anomaly list describes the known bugs, anomalies, and workarounds for the ADIS16488A. Analog Devices, Inc., is committed, through future silicon revisions, to continuously improve silicon functionality. Analog Devices tries to ensure that these future silicon revisions remain compatible with your present software/systems by implementing the recommended workarounds outlined within this document.
PERFORMANCE ISSUES Table 1. Error in Soft Iron Correction Factors [er001] Background
The signal chain for the tri-axis magnetometer in the ADIS16488A includes a user-configurable, 3 × 3 soft iron correction matrix. Users configure each value in the soft iron correction matrix by writing to its corresponding register. For example, the SOFT_IRON_S12 register contains the value for correction factor S12. In these registers, 1 LSB = 100/215.
Issue
On units that have firmware Revision 1.07 (or earlier), 1 LSB = 12.5/215, which is eight times lower than the correct value, on the following registers: SOFT_IRON_S12, SOFT_IRON_S13, SOFT_IRON_S21, SOFT_IRON_S31, and SOFT_IRON_S32.
Workaround
Read FIRM_REV to determine the firmware revision of a unit. If FIRM_REV < 0x0108, clear all soft iron correction values (write 0x0000 to each SOFT_IRON_Sxy register) and perform the soft iron correction outside of the ADIS16488A.
Related Issues
None.
Table 2. User Offset Addition Error [er002] Background
The ADIS16488A provides user-configurable bias correction values for each gyroscope and accelerometer(x, y, and z), through the fol owing registers: XG_BIAS_HIGH, XG_BIAS_LOW, YG_BIAS_HIGH, YG_BIAS_LOW, ZG_BIAS_HIGH, ZG_BIAS_LOW, XA_BIAS_HIGH, XA_BIAS_LOW, YA_BIAS_HIGH, YA_BIAS_LOW, ZA_BIAS_HIGH, and ZA_BIAS_LOW.
Issue
On units that have firmware Revision 1.07 (or earlier), there is a computation error that results in a small error in the bias of each sensor (for example, less than 0.02°/sec for the gyroscopes).
Workaround
Read FIRM_REV to determine the firmware revision of a unit. If FIRM_REV < 0x0108, write 0x0000 to XG_BIAS_HIGH, XG_BIAS_LOW, YG_BIAS_HIGH, YG_BIAS_LOW, ZG_BIAS_HIGH, ZG_BIAS_LOW, XA_BIAS_HIGH, XA_BIAS_LOW, YA_BIAS_HIGH, YA_BIAS_LOW, ZA_BIAS_HIGH, and ZA_BIAS_LOW. Apply the bias correction factors to the gyroscope and accelerometer signals outside of the ADIS16488A.
Related Issues
None.
Table 3. Temperature Compensation Error [er003] Background
The ADIS16488A leverages internal temperature sensors as control inputs for the compensation of gyroscope and accelerometer measurements.
Issue
On units that have firmware Revision 1.08 (or earlier), one of the three temperature sensors can be corrupted when using an external clock to drive the sampling. The external clock causes elevated levels of sensitivity to variation in temperature.
Workaround
Read FIRM_REV to determine the firmware revision of a unit. If FIRM_REV < 0x0109, use the internal sample clock if the best temperature sensitivity is necessary.
Related Issues
None.
Table 4. Real-Time Clock (RTC) Functional Issues [er004] Background
The ADIS16488A provides a RTC function that keeps track of time (seconds, minutes, hours, days, months, and years) while the main processor function is not operating (sleep, powered off).
Issue
On units that have firmware Revision 1.08 (or earlier), the days information in TIME_DH_OUT can experience an overflow condition when the device recovers from sleep mode.
Workaround
Read FIRM_REV to determine the firmware revision of a unit. If FIRM_REV < 0x0109, do not use sleep mode if the RTC function is critical for the application.
Related Issues
None.
Rev. 0 Document Feedback 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 One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Tel: 781.329.4700 ©2017 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. Technical Support www.analog.com
Document Outline PERFORMANCE ISSUES ANOMALY STATUS
