ST面向手持设备的MEMS解决方案ST

简介：MEMS(Micro Electro Mechanical System，即微电子机械系统)是指集微型传感器以及信号处理和控制电路、接口电路于一体的微型机电系统。MEMS 技术集成了能够对震动，位移，加速度，旋转进行灵敏检测的机械部分，从而为制造小体积，低成本的传感器开创了新的道路。ST基于MEMS技术的传感器可以分为以下四种：MEMS动作传感器，MEMS压力传感器，MEMS射频器件，MEMS微流体器件。
本次座谈将主要介绍ST公司的MEMS动作传感器（线性加速计/陀螺仪）LIS302系列产品包括模

问：数据表中的"Offset can be eliminated by enabling the built-in high pass filter (HPF)"是漂移补偿吗?如果是,是温漂还是时漂?如果不是,烦请说明,谢谢!
答： When high-pass-filter is turned on, the DC level of the MEMS is utilized to 0. Therefore, "Offset can be eliminated by enabling the built-in high pass filter (HPF)". I must highlight that this is not a compensation. Using hardware engineer point

问：对演示中提到的硬盘防盗感兴趣，但是只是一提而过，能否详细解释一下？
答： when notebook or Harddisk is in steady stage, you can set the threshold, when someone take notebook or harddisk, it will above threshold that trigger antitheft function, so your system can react accordingly.

问：1.除手机，GPS等外，MWMS能否更深入的进入大众阅读市场,如电子纸张阅读，产品的盒外电子包装?
2.MEMS麦克风开始热门，能简单介绍它的主要应用面吗？
答： 1. Yes, it can be used for browsing, portrait-landscape swith in eNewspaper application.
2. MEMS microphone advantage is smaller size and very low power consumption. Good sensitivity.

问：ST的3轴MEMS加速度传感器如LIS3L02AQ5和Freescale的MMA7260Q相比,有什么特点和优势?
答： Please contact ST directly for the comparison table.

问：一个性能良好的MEMS,至少要包括那几部分?
答： good sensitivity.
good 0g-offset.
good temperature stability.

问：MEMS在硬盘中的保护功能是如何进行的?响应时间有多快?
答： In harddisk protection, we can use for shock/vibration( > threshold setting e.g. >100mg) and for freefall protection (<threhold setting e.g <350mg). The response timing for sensor is very fast. ST already have many branded notebook maker use it

问：关于ST的MEMS加速度计的带宽配置是通过何种方式实现的？
答： Use LIS3L02AL as example, bandwidth =1/(2*Pi*Rl*Cf)
Where Pi is a constant 3.1415….
Rl is the internal loading resistor which is fixed at 110kOhm for LIS3L02AL
Cf is the external filtering/loading capacitor which can be determined by u

问：MEMS需要校准吗?如何对MEMS进行校准?出厂后的校准如何进行?
答： ST MEMS are 100% calibrated for sensitivity and 0-g offset before shipment. Ingeneral, it does not require further calibration at customers site, unlike some other competitors.

问：MEMS动作传感器X,Y位移数据输出的格式是怎么样的? 请推荐几款对应的MPU产品?
答： I used ST74F264 and ST7Lite before. Anyway, the output format is configurable for ST’s digital MEMS to suite all type of MPU. For LIS3LV02DQ, please see BLE bit and DAS bit detail description in CTRL_REG2 (21h).

问：贵公司如何保证MEMS传感器的稳定性？
答： In sensor design, we have stopper to limit maximum sensor movement that withstand high shock at 10,000g at 0.1msec duration.
In ST factory, we also perform strictly reliability test. The reliabilty is gurantee in our specification.