EasyEDA硬件开源项目——基于ADXL345 的3轴加速计模块

Description:

This new version adds 2 standoff holes as well as an extra decoupling capacitor. The ADXL345 is a small, thin, low power, 3-axis MEMS accelerometer with high resolution (13-bit) measurement at up to +-16 g. Digital output data is formatted as 16-bit twos complement and is accessible through either a SPI (3- or 4-wire) or I2C digital interface.

The ADXL345 is well suited to measures the static acceleration of gravity in tilt-sensing applications, as well as dynamic acceleration resulting from motion or shock. Its high resolution (4 mg/LSB) enables measurement of inclination changes less than 1.0 degrees;.

Several special sensing functions are provided. Activity and inactivity sensing detect the presence or lack of motion and if the acceleration on any axis exceeds a user-set level. Tap sensing detects single and double taps. Free-fall sensing detects if the device is falling. These functions can be mapped to one of two interrupt output pins. An integrated, patent pending 32-level first in, first out (FIFO) buffer can be used to store data to minimize host processor intervention. Low power modes enable intelligent motion-based power management with threshold sensing and active acceleration measurement at extremely low power dissipation.

Features:

2.0-3.6VDC Supply Voltage

Ultra Low Power: 40uA in measurement mode, 0.1uA in standby@ 2.5V

Tap/Double Tap Detection

Free-Fall Detection

SPI and I2C interfaces

描述:

这个新版本的芯片添加两个有支架的过孔以及一个多余的耦合电容。ADXL345是一个小型的，薄，低功耗，有高分辨率（13bit）测量值高达+-16 g 的3轴MEMS加速度计。数字输出数据以一个16位的两个完整的并且可以通过SPI（3 wires 或者4 wires）或者i2c 数字接口通信。

ADXL345很适合在倾斜传感应用中测量静态的重力加速度，以及由于运动或者撞击产生的动态加速度。 他的高分辨率（(4 mg/LSB) ）使得倾斜变化的测量小于1°。

提供了几个特殊的感应功能。运动和非运动感应检测运动的存在或者不存在，并且如果在任何一个轴都的加速度超过用户设定的值。点击感应检测单击和双击。自由落体检测当这个器件下落的时候。这些功能都可以映射到一个或者两个中断输出引脚。一个集成性的，专利申请中的32 水平的先进先出缓冲器可以用于保存数据以最小化主处理器的干涉。 低功耗的模式使得在极低的功率损耗下智能的基于运动的电源管理拥有阈值检测和活跃的加速度测量成为可能。

特性：

2.0-3.6VDC 供电电压

超低功耗：测量模式下40uA ， 在2.5V下的备用模式是01.uA。

单击或者双击检测

自由落体检测

SPI和I2C接口