 |
Electronic Components Datasheet Search |
|
|
Electronic Components Datasheet Search |
|
ADXL363 Datasheet(PDF) 18 Page - Analog Devices |
|
||||||||||||||||||||||||||||||
ADXL363 Datasheet(HTML) 18 Page - Analog Devices |
|
|
18 / 48 page  ADXL363 Data Sheet Rev. 0 | Page 18 of 48 When using referenced inactivity detection, inactivity is detected when acceleration samples are within a user specified amount of an internally defined reference (as described by Equation 2) for a user defined amount of time. |Acceleration – Reference| < Threshold (2) The reference for inactivity detection is updated every time a sample is detected that violates the inactivity condition; that is, (Sample – Reference) ≥ Threshold. Referenced inactivity, like referenced activity, is particularly useful for eliminating the effects of the static acceleration due to gravity. With absolute inactivity, if the inactivity threshold is set lower than 1 g, a device resting motionless may never detect inactivity. With referenced inactivity, the same device under the same configuration detects inactivity. The inactivity timer can be set to anywhere from 2.5 ms (a single sample at 400 Hz ODR) to almost 90 minutes (65,535 samples at 12.5 Hz ODR) of inactivity. A requirement for inactivity detec- tion is that, for whatever period of time the inactivity timer has been configured, the accelerometer detects inactivity only when it has been stationary for that amount of time. For example, if the accelerometer is configured for 90 minutes, the accelerometer detects inactivity when it is stationary for 90 minutes. The wide range of timer settings means that in applications where power conservation is critical, the system can be put to sleep after very short periods of inactivity. In applications where continuous operation is critical, the system stays on for as long as any motion is present. Linking Activity and Inactivity Detection The activity and inactivity detection functions can be used independently and processed manually by a host processor, or they can be configured to interact in linked mode, loop mode, and autosleep. Default Mode The user must enable the activity and inactivity functions because these functions are not automatically enabled by default. After the user enables the activity and inactivity functions, the ADXL363 exhibits the following behavior when it enters default mode: • Both activity and inactivity detection remain enabled • All interrupts must be serviced by a host processor; that is, a processor must read each interrupt before it is cleared and can be used again. Default mode operation is illustrated in the flowchart in Figure 31. Linked Mode In linked mode, activity and inactivity detection are linked to each other such that only one of the functions is enabled at any given time. As soon as activity is detected, the device is assumed moving (or awake) and stops looking for activity; rather, inactivity is expected as the next event. Therefore, only inactivity detection operates. Similarly, when inactivity is detected, the device is assumed stationary (or asleep). Thus, activity is expected as the next event; therefore, only activity detection operates. Figure 31. Flowchart Illustrating Activity and Inactivity Operation in Default Mode In linked mode, each interrupt must be serviced by a host processor before the next interrupt is enabled. Linked mode operation is illustrated in the flowchart in Figure 32. Figure 32. Flowchart Illustrating Activity and Inactivity Operation in Linked Mode Loop Mode In loop mode, motion detection operates as described in the Linked Mode section, but interrupts do not need servicing by a host processor. This configuration simplifies the implementation of commonly used motion detection and enhances power savings by reducing the amount of power used in bus communi- cation. Loop mode operation is illustrated in the flowchart in Figure 33. Figure 33. Flowchart Illustrating Activity and Inactivity Operation in Loop Mode WAIT FOR ACTIVITY EVENT ACTIVITY INTERRUPT TRIGGERS NOTES 1. THE AWAKE BIT DEFAULTS TO 1 WHEN ACTIVITY AND INACTIVITY ARE NOT LINKED. WAIT FOR INACTIVITY EVENT INACTIVITY INTERRUPT TRIGGERS WAIT FOR PROCESSOR TO CLEAR INTERRUPT WAIT FOR PROCESSOR TO CLEAR INTERRUPT AWAKE = 1 AWAKE = 1 WAIT FOR ACTIVITY EVENT ACTIVITY INTERRUPT WAIT FOR INACTIVITY EVENT INACTIVITY INTERRUPT AWAKE = 0 AWAKE = 1 WAIT FOR PROCESSOR TO CLEAR INTERRUP WAIT FOR PROCESSOR TO CLEAR INTERRUPT WAIT FOR ACTIVITY EVENT WAIT FOR INACTIVITY EVENT AWAKE = 0 AWAKE = 1 |
Similar Part No. - ADXL363 |
|
Similar Description - ADXL363 |
|
|
Link URL |
| Privacy Policy |
| ALLDATASHEET.COM |
| Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Datasheet Upload | Contact us | Privacy Policy | Link Exchange | Manufacturer List All Rights Reserved©Alldatasheet.com |
| Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
|
Family Site : ic2ic.com |
icmetro.com |
English ▼
English
Chinese
German
Japanese
Russian
Korean
Spanish
French
Italian
Portuguese
Polish
Vietnamese
Indian
Mexican
British
New Zealand
