Datasheet ADXL344 (Analog Devices) - 5

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ADXL344 Data Sheet Parameter Test Conditions/Comments Min1 Typ2 Max
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Unit
TEMPERATURE Operating Temperature Range −40 +85 °C WEIGHT Device Weight 18 mg 1 All minimum and maximum specifications are guaranteed. Typical specifications are not guaranteed. 2 The typical specifications shown are for at least 68% of the population of parts and are based on the worst case of mean ±1 σ except for 0 g output and sensitivity, which represents the target value. For 0 g offset and sensitivity, the deviation from the ideal describes the worst case of mean ±1 σ. 3 Cross-axis sensitivity is defined as coupling between any two axes. 4 Bandwidth is the −3 dB frequency and is half the output data rate bandwidth = ODR/2. 5 The output format for the 3200 Hz and 1600 Hz ODRs is different from the output format for the remaining ODRs. This difference is described in the Data Formatting of Upper Data Rates section. 6 Output data rates below 6.25 Hz exhibit additional offset shift with increased temperature, depending on selected output data rate. Refer to the Offset Performance at Lowest Data Rates section for details. 7 These are typical values for the lowest and highest output data rate settings. 8 Self-test change is defined as the output (g) when the SELF_TEST bit = 1 (in the DATA_FORMAT register, Address 0x31) minus the output (g) when the SELF_TEST bit = 0. Due to device filtering, the output reaches its final value after 4 × τ when enabling or disabling self-test, where τ = 1/(data rate). The part must be in normal power operation (LOW_POWER bit = 0 in the BW_RATE register, Address 0x2C) for self-test to operate correctly. 9 Turn-on and wake-up times are determined by the user-defined bandwidth. At a 100 Hz data rate, the turn-on and wake-up times are each approximately 11.1 ms. For other data rates, the turn-on and wake-up times are each approximately τ + 1.1 in milliseconds, where τ = 1/(data rate). Rev. 0 | Page 4 of 40 Document Outline Features Applications General Description Functional Block Diagram Revision History Specifications Absolute Maximum Ratings Thermal Resistance Package Information ESD Caution Pin Configuration and Function Descriptions Typical Performance Characteristics Theory of Operation Power Sequencing Power Savings Power Modes Autosleep Mode Standby Mode Serial Communications SPI Preventing Bus Traffic Errors I2C Interrupts DATA_READY Bit SINGLE_TAP Bit DOUBLE_TAP Bit Activity Bit Inactivity Bit FREE_FALL Bit Watermark Bit Overrun Bit Orientation Bit FIFO Bypass Mode FIFO Mode Stream Mode Trigger Mode Retrieving Data from FIFO Self-Test Register Map Register Definitions Register 0x00—DEVID (Read Only) Register 0x1D—THRESH_TAP (Read/Write) Register 0x1E, Register 0x1F, Register 0x20—OFSX, OFSY, OFSZ (Read/Write) Register 0x21—DUR (Read/Write) Register 0x22—Latent (Read/Write) Register 0x23—Window (Read/Write) Register 0x24—THRESH_ACT (Read/Write) Register 0x25—THRESH_INACT (Read/Write) Register 0x26—TIME_INACT (Read/Write) Register 0x27—ACT_INACT_CTL (Read/Write) ACT AC/DC and INACT AC/DC Bits ACT_x Enable Bits and INACT_x Enable Bits Register 0x28—THRESH_FF (Read/Write) Register 0x29—TIME_FF (Read/Write) Register 0x2A—TAP_AXES (Read/Write) Improved Tap Bit Suppress Bit TAP_x Enable Bits Register 0x2B—ACT_TAP_STATUS (Read Only) ACT_x Source and TAP_x Source Bits Asleep Bit Register 0x2C—BW_RATE (Read/Write) LOW_POWER Bit Rate Bits Register 0x2D—POWER_CTL (Read/Write) Link Bit AUTO_SLEEP Bit Measure Bit Sleep Bit Wakeup Bits Register 0x2E—INT_ENABLE (Read/Write) Register 0x2F—INT_MAP (Read/Write) Register 0x30—INT_SOURCE (Read Only) Register 0x31—DATA_FORMAT (Read/Write) SELF_TEST Bit SPI Bit INT_INVERT Bit FULL_RES Bit Justify Bit Range Bits Register 0x32 to Register 0x37—DATAX0, DATAX1, DATAY0, DATAY1, DATAZ0, DATAZ1 (Read Only) Register 0x38—FIFO_CTL (Read/Write) FIFO_MODE Bits Trigger Bit Samples Bits Register 0x39—FIFO_STATUS (Read Only) FIFO_TRIG Bit Entries Bits Register 0x3A—TAP_SIGN (Read Only) xSIGN Bits xTAP Bits Register 0x3B—ORIENT_CONF (Read/Write) INT_ORIENT Bit Dead Zone Bits INT_3D Bit Divisor Bits Register 0x3C—Orient (Read Only) Vx Bits xD_ORIENT Bits Applications Information Power Supply Decoupling Mechanical Considerations for Mounting Tap Detection Improved Tap Detection Tap Sign Threshold Link Mode Sleep Mode vs. Low Power Mode Offset Calibration Using Self-Test Orientation Sensing Data Formatting of Upper Data Rates Noise Performance Operation at Voltages Other Than 2.6 V Offset Performance at Lowest Data Rates Axes of Acceleration Sensitivity Layout and Design Recommendations Outline Dimensions Ordering Guide