| 在线座谈主题：奇妙的飞思卡尔™加速传感器 |
| [ 问题 1 ] |
请问该传感器使用的极限环境温度范围? |
| [ 答案 1 ] |
-20 ~ 85 degree C.
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| [ 问题 2 ] |
请问加速度传感器的抗过载能力怎样? |
| [ 答案 2 ] |
2000g. But it can be higher for short period. When we talk about Max g overload, we need to see the period as well.
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| [ 问题 3 ] |
MMA7260Q 的内部加速度采样速率是多少?什么样的 A/D 采样率和什么样的电源开关频率才能不影响加速度计的采样? |
| [ 答案 3 ] |
MMA7260Q 是 11KHz, 400Hz 以下会影响加速度的采样。
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| [ 问题 4 ] |
加速度能否与 GPS 配套使用作为在 GPS 无信号时导航用，是否必需 3 轴传感器? |
| [ 答案 4 ] |
Accelerometer can be used in GPS DR. But it may need 2 3-axis accelerometer and 1 Gyroscpoe to complete the application. One accelerometer is not enough for GPS DR.
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| [ 问题 5 ] |
加速传感器与车速传感的区别? |
| [ 答案 5 ] |
Accelerometer can detect acceleration without any external equipment. So it is convenient to install and use to detect acceleration, speed and distance.
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| [ 问题 6 ] |
感应轴与X、Y、Z轴有何不同?做倾斜测量时，对感应轴的方向有何要求?
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| [ 答案 6 ] |
All axes are the same except sensitivity and bandwidth spec. There is no any installation request for 3-axes sensor. However, it must be limit user's installation angle when use two-axes sensor.
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| [ 问题 7 ] |
该传感器是什么接口类型?
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| [ 答案 7 ] |
Analog output.
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| [ 问题 8 ] |
6g 的震动对 MMA7260Q 的输出会有多大的影响?
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| [ 答案 8 ] |
Assuming you have set MMA7260Q to 6g, then you need to work out what 6g corresponds to in terms of your full scale voltage output and map this to your A/D reading. So, one expects 6g to be close to VDD or near 255 for 8bit A/D.
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| [ 问题 9 ] |
如何用此芯片构建一个使用的最小系统? 飞思卡尔是否提供解决方案?
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| [ 答案 9 ] |
It is because Freescale's accelerometer must be used with MCU to achieve the function. Freescale can support small package MCU to build up a small system board.
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| [ 问题 10 ] |
请问加速度传感器应用于人体输入学设备有无比较成熟的产品?
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| [ 答案 10 ] |
Current sensor can be used but algrothem is needed.
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| [ 问题 11 ] |
Z 轴与 X , Y 轴的灵敏度相同吗?
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| [ 答案 11 ] |
For the 3 axis, in the strictist sense, yes but all three axis of our devices are very close and our spec is 0.8V/g. That is why we have a X-axis sensitivity spec as well (5%).
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| [ 问题 12 ] |
飞思卡尔加速传感器有什么突出的优点和性能?
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| [ 答案 12 ] |
Freescale accelerometer has best electronic performance in terms of power consumption (Idd 0.5mA) vs sensitivity (800mV/g) vs noise (4.7mVrms). Also fastest response time typical 1ms power on response, 0.5mS from sleep mode to on. 4 G range selectable. This means one device can be used for 1.5g, 2g, 4g and 6g in one end product. Price/Value comparison is very good.
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| [ 问题 13 ] |
在飞思卡尔 MMA7260Q 新闻发布网页看到 "无线传感器网络技术" 的提法，请问该技术是何概念?加速度传感器与它有何联系? |
| [ 答案 13 ] |
Freescale has another wireless chip Zigbee. Transmitting sensor output with Zigbee, it can accomplish small wireless network application. |
| [ 问题 14 ] |
飞思卡尔是否会在近期内提供高重力加速度传感器（40g以上），以支持汽车碰撞检测? |
| [ 答案 14 ] |
Freescale has sensors g range from 1.5g up to 250g. We have shipped hundreds million 40g above sensor for car crash (airbag application).
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| [ 问题 15 ] |
MMA7260Q 加速度传感器的 ESD 保护性能如何? |
| [ 答案 15 ] |
HB ESD 2kV.
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| [ 问题 16 ] |
请问温度补偿如何处理?是要用户处理，还是 IC 本身自己进行了处理? |
| [ 答案 16 ] |
IC 内部有处理, 不需用户处理。
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| [ 问题 17 ] |
奇妙的飞思卡尔加速传感器在多媒体电子产品方面有哪些具体用途? |
| [ 答案 17 ] |
It can use for HDD freefall detection, menu-scrolling, power-saving, stolen alarm, tilt detection and pattern recognition.
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| [ 问题 18 ] |
加速传感器在环境测量中会有什么应用呢? |
| [ 答案 18 ] |
It can detect bridge or dam for vibration or tilt angle monitoring.
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| [ 问题 19 ] |
该加速传感器支持三维感应吗? |
| [ 答案 19 ] |
MMA7260Q can support 3-axes acceleration detection with only one chip.
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| [ 问题 20 ] |
作倾斜角测量时，若物体倾斜后静止，此时所有输出是否均为0? |
| [ 答案 20 ] |
No because you will always have a measure of gravity acting on it (ie the cosine of the angle x g).
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| [ 问题 21 ] |
请问飞思卡尔是否有位移传感器或速度传感器之类的产品? |
| [ 答案 21 ] |
No.
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| [ 问题 22 ] |
飞思卡尔有没有基于 MEMS 技术的为微压力传感器，分辨率达到 0.5g 或更精度更高的? |
| [ 答案 22 ] |
Our accelerometers are for acceleration measurements and not for pressure. Our full span is +/-1.5g. If you want 0.5g then our sensor can still detect this.
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| [ 问题 23 ] |
请问飞思卡尔加速传感器的频响范围是多少? 最低频响是多少? |
| [ 答案 23 ] |
Our accelerometers range from dc to 350Hz for X and Y axis and around 200Hz for Z axis. The minimum frequency response depends on the loading of the low pass filter or the A/D converter that is connected to it. Pls refer to Freescale MMA7260Q datasheets.
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| [ 问题 24 ] |
传感器的精度如何?倾角能达到多少精度? |
| [ 答案 24 ] |
Our accelerometers do not have an non linear response. The tilt accuracy depends on a number of things:
a. Noise level of your system
b. Sensitivity of device selected
c. A/D resolution
d. What area of the response curve are you in with the angle of interests.
To give you an idea, our MMA6260 device with sensitivity of 0.8V/g and using an A/D of 10bit will give accuracy of 0.229 at 0 degrees (highest sensitivity point of the response). This will improved with increased A/D resolutions.
|
| [ 问题 25 ] |
a. 由加速度值积分求速度、位移，累计误差如何考虑，大致范围多大，有无试验结果?
b. 飞思卡尔提供的加速度传感器频响特性如何?频带宽度? |
| [ 答案 25 ] |
Our sensor is able to measure acceleration within good accuracy +/-7.5%. But to integrate with time, errors will accumulate and one needs to like at the initial raw data and determine what is needed before processing. So the answer depends on how accurate have you capture the raw data and it would be expected that the user knows what is going on with the exact movement of the sensor. Unfortunately, we do not have analysis done for position with respect to accuracy because this is highly dependent on the degree of data capturing and algorthim used.
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| [ 问题 26 ] |
大小如何，灵敏度如何? |
| [ 答案 26 ] |
Our size is 6x6x1.45mm in size for our tri-axis sensor. Our sensor is able to measure acceleration within good accuracy +/-7.5% for a fullscale span of 2g. This will go up significantly for very high g range devices.
|
| [ 问题 27 ] |
请问汽车侧向加速度的测量采用什么型号的传感器? |
| [ 答案 27 ] |
Part No. as MMA2260D.
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| [ 问题 28 ] |
请介绍 MMA7260Q 加速度传感器的输出性能, 能否直接和 ADC 相连接? |
| [ 答案 28 ] |
Please refer MMA7260Q datasheet which can down loaded from Freescale Sensor website. Yes, it can connect to ADC directly.
|
| [ 问题 29 ] |
可以提供方案么? 我公司品想测量角度, 是否能派上用场? |
| [ 答案 29 ] |
Pls refer to our application note (AN3107). We have methods for doing tilt measurements.
|
| [ 问题 30 ] |
请介绍 MMA7260Q 加速度传感器内部滤波器的性能, 它的截止频率有多高? |
| [ 答案 30 ] |
Sensing element resonant frenqency XY at 6kHz, Z at 3.4kHz. Bandwidth response XY at 350Hz, Z at 150Hz.
|
| [ 问题 31 ] |
请问陀螺传感器、速度传感器和加速传感器的区别? |
| [ 答案 31 ] |
The accelerometer can use to detect linear acceleration. However, the gyro is used to detect angular acceleration.
|
| [ 问题 32 ] |
能否提供应用电路? 是采用那种耦合方式? 如何进行敏感轴校准? |
| [ 答案 32 ] |
The accelerometer datasheet provides application circuits. The sensor output is series 1K ohms resistor to MCU A/D pin. There is detailed information about calibration on the application note (AN1986) which is available on Freescale website.
|
| [ 问题 33 ] |
MMA1260 与 MMA6260 的采样率分别是多少? |
| [ 答案 33 ] |
The bandwidth response is 50Hz for the two chips.
|
| [ 问题 34 ] |
目前市场上有多种类型的加速度传感器产品，有的是基于压电晶体，有的则基于电容、电阻应变片等。请问芯片化的加速度传感器与这些传统的加速传感器相比，有什么样的特点? |
| [ 答案 34 ] |
The benefit to use silicon device is to save power consumption, increase reliability, digital data to analyze and save system design PCB space.
|
| [ 问题 35 ] |
加速度芯片对焊接、安装有什么特殊要求? |
| [ 答案 35 ] |
The detailed information can be found from application notes: AN1902 and DL200 which are available on Freescale website.
|
| [ 问题 36 ] |
我想用这个作一个测量汽车行驶加速德的装置，通过积分来实现汽车行驶速度测量，请问累积误差会在允许范围内码? |
| [ 答案 36 ] |
The error depends on many factors, including A/D sampling rate, A/D conversion resolution, the sensor sensitivity and noise distorsion. So it is important to select high sensitivity and bandwidth sensor.
|
| [ 问题 37 ] |
如何有效抗汽车的高频干扰? |
| [ 答案 37 ] |
The sensor output purity depends on the input power. There is detailed information about power design on the application note (AN1988). It can be found on Freescale website.
|
| [ 问题 38 ] |
请问C－V变换后为什么采样，直接输出不可以吗? |
| [ 答案 38 ] |
There are many reasons for this. For one thing, we have an integrator on board and we need to perform sampling to acquire the value of the capacitance of the sensor. So there would be switching noises. For this signal conditioning and filter is performed. Also we have temperature compensation circuitries.
|
| [ 问题 39 ] |
在飞思卡尔网站上看到, 三星电子在数字音频播放器中采用了加速度传感器, 通过倾斜和自由下落检测实现了滚动菜单的功能, 请做详细介绍? |
| [ 答案 39 ] |
There is detailed information on the application notes: AN3107 and AN1986 which are available on Freescale website.
|
| [ 问题 40 ] |
加速度传感器的感应下限是多少? |
| [ 答案 40 ] |
There is no under limit for accelerometer.
|
| [ 问题 41 ] |
MMA7260Q 加速度传感器随加速度和电源电压的线性性能如何? |
| [ 答案 41 ] |
There is temperature compensation circuits in Freescale accelerometer. So the output linearity is good.
|
| [ 问题 42 ] |
请问加速度计的带宽是指 C-V Convertor 的采样速率还是最终输出模拟信号的采样速率? |
| [ 答案 42 ] |
There is an internal low pass filter that shapes the bandwidth response to 350Hz for X axis; Y axis and 150Hz-200Hz for Z axis. Then this might be impaired by the external loading from your filtering caps or ADC. So it depends where the bottleneck is with respect to loading on our device.
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| [ 问题 43 ] |
三轴加速计有数子输出的吗? 如果没有能否做到数字输出, 大约时间要多久. 现有产品只有 IIC 接口, 而 MMA7260Q 只有模拟输出, 在不用有 AD 转换的 MCU 时, 有没有其它办法可以解决? |
| [ 答案 43 ] |
We do not have digital output at moment.
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| [ 问题 44 ] |
加速度传感器可否应用在液体流量控制中? |
| [ 答案 44 ] |
We have not experimented with this but asuming that you have the device well protected from water, it can work fine. But then it depends on what you are trying to achieve. And relative fluid viscosity needs to be taken into account. Other than this we have no further inputs.
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| [ 问题 45 ] |
对于加速度不稳定的测量有自动调节么?就是会不会根据 G 值变化自动调节?还是需要 MCU 调节? |
| [ 答案 45 ] |
Yes, according to different G-level to adjust G-select pin by MCU.
|
| [ 问题 46 ] |
飞思卡尔加速传感器属于 MEMS（微机械电子系统）器件么?家电行业有什么应用? |
| [ 答案 46 ] |
Yes, the accelerometer is MEMS device. It can be used in washing machine to detect motor vibration for safety control.
|
| [ 问题 47 ] |
这个产品是否可以用于手机, 作一些游戏方面的应用? |
| [ 答案 47 ] |
Yes. MMA7260Q has high sensitivity. It is good for hand held game application. Because hand held devices, LCD can move very fast otherwise user will not able to see the image from LCD clearly due to shaking. So high sensitivity is necessary in many games which use tilt.
|
| [ 问题 48 ] |
一般来说, 加速度传感器对电源的波纹要求高吗? |
| [ 答案 48 ] |
Yes. Power suply must be clean.
|
| [ 问题 49 ] |
在 "车载运动中卫星通信" 系统里，飞思卡尔加速传感器是否具有应用价值? |
| [ 答案 49 ] |
Yes. We have some customers use Freescale accelerometers in this application.
|
| [ 问题 50 ] |
低重力加速度传感器主要用于哪里? |
| [ 答案 50 ] |
Pls access Freescale sensor website to get detailed application from MMA7260Q factsheet. http://www.freescale.com.cn/Products/sensors/MMA7260Q_Overview.asp
|
| [ 问题 51 ] |
2 轴加速度传感器如何消除机械安装产生的方向性误差 (芯片焊接不完成平行于 PCB， 芯片方向于仪器外壳标住记方向间误差)? 这个误差能否计算出来? |
| [ 答案 51 ] |
You need to refer to our application note (AN3107). Basically you need to detemine the reference point for which the sensor is mounted. To obtain the most resolution per degree of change, the IC should be mounted with the sensitive axis parallel to the plane of movement where the most sensitivity is desired. For example, if the degree range that an application will be measuring is only 0° to 45° and the PCB will be mounted perpendicular to gravity, then an X-Axis device would be used. With this then your reference point is the initial mounting of the device and your reference angle would be the cosine of that sensor axis to gravity. Yes you can determine the error by taking one measurement with one A/D step change at various points of your scale (ie 0 degree, +90 degree etc).
|
| [ 问题 52 ] |
MMA7260Q 的内部采样率是 11KHZ, 是不是说 A/D 采样率太低就会影响内部采样? |
| [ 答案 52 ] |
不是。内部采样是固定的。
|
| [ 问题 53 ] |
硬盘内置加速器传感器来保护硬盘是怎么回事? |
| [ 答案 53 ] |
当硬盘不慎掉落时, 加速器传感器会侦查到而将硬盘的指针回到原本位置以避免指针刮伤到硬盘的磁道 。
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| [ 问题 54 ] |
请问能否用来测量环境中墙壁，窗户等的震动?例如：汽车，飞机经过时窗户玻璃的震动... |
| [ 答案 54 ] |
可以。
|
| [ 问题 55 ] |
请问采用 MMA7260Q 可否作为一般的震动检测? |
| [ 答案 55 ] |
可以作为一般的震动检测。
|
| [ 问题 56 ] |
请问汽车侧向加速度的测量能采用什么类型的加速度传感器? |
| [ 答案 56 ] |
可用X-Y轴传感器 (You can use X-Y sensor for tilt detect for automotive)。
|
| [ 问题 57 ] |
飞思卡尔的加速度传感器有频率下限吗?是多少呢? |
| [ 答案 57 ] |
没有频率下限。
|
| [ 问题 58 ] |
如何申请飞思卡尔有关传感器或其它方面的芯片吗?如果能程序是怎样的? |
| [ 答案 58 ] |
你可在飞思卡尔网站免费申请样品
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| [ 问题 59 ] |
加速计传感器如何在 MP3 设计方案中添加，通过什么总线控制? |
| [ 答案 59 ] |
如有 AD 接口, 可经 RC filter 直接连。 如没有, 可加 MCU 或 ADC 在中间, 通过 SPI 或 IIC 控制。加 MCU 的优点是在 MP3 关机的时候, 可加一些增值功能 (如计步器或防盗)。
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| [ 问题 60 ] |
加速度传感器能否同时提供 X、 Y、 Z 三个方向上的加速度信号? |
| [ 答案 60 ] |
三轴加速度传感器可同时提供 X、Y、Z 三个方向上的加速度信号。
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| [ 问题 61 ] |
三轴加速度传感器是否 X, Y 和 Z 三轴都有输出? 此时 MCU 如何判断? 是"与功能"还是"或功能"? |
| [ 答案 61 ] |
是, 要有三个 AD 囗来分别三轴。
|
| [ 问题 62 ] |
请问用 MMA6260 开发电脑鼠标是客户还是 IDH ?
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| [ 答案 62 ] |
是 IDH。
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| [ 问题 63 ] |
MMA7260Q 加速度传感器的输出能力有多大? 能和那种类型接口?
|
| [ 答案 63 ] |
它是 Analog 输出, 从 0+0.25V 到 Vdd-0.25V。可接 AD 口。
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| [ 问题 64 ] |
请问 MMA6260Q 可否用于电脑鼠标的开发? |
| [ 答案 64 ] |
我们有伙伴正在开发。
|
| [ 问题 65 ] |
芯片除 RS232, 还提供哪些外部接口呢? |
| [ 答案 65 ] |
芯片没有 RS232, 只有 Analog 输出。
|
| [ 问题 66 ] |
加速度传感器如何防范时钟对性能的干扰? |
| [ 答案 66 ] |
要看看时钟频率和走线。
|
| [ 问题 67 ] |
在用 MMA7260Q 时, 如何选择 g, 也就是说怎么知道我所应用的 g 的范围, 比如震动过程, g 的大小如何确定的? |
| [ 答案 67 ] |
要看看最大加速度的数值, MMA7260Q 的好处是可变换这值-所以, 可以当 AD 的值过大时, 变换更大的最大加速度值；相反, 当 AD 值小时, 变换更小值, 从而得到更敏感的加速度。
|
| [ 问题 68 ] |
请问用加速度传感器数据两次积分求位移这种方法是否能在工程实际当中使用? |
| [ 答案 68 ] |
要考虑地心引力的影响, 可用 Numerical Method 的方法计算, 位移一般不会很准确。
|
| [ 问题 69 ] |
请问用 MMA6260 开发电脑鼠标需要注意哪些方面的问题? |
| [ 答案 69 ] |
要注意地心引力, 在没有加速的情形下是不能测知。
|
| [ 问题 70 ] |
请问谁是飞思卡尔加速传感器福建代理?同时飞思卡尔的其它器件是否也有代理? |
| [ 答案 70 ] |
以下是飞思卡尔代理商在厦门联系信息, 您亦可按 "地区检索" 查看其它地区： http://www.freescale.com.cn/others/wheretobuy/location4.asp
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| [ 问题 71 ] |
请问今后的传感器能否把各种应用的算法做进去，用户只需进行读写操作就可以了? |
| [ 答案 71 ] |
应用的范围太广了, 配 MCU 便可。
|
| [ 问题 72 ] |
请问汽车侧向加速度的测量采用什么类型的传感器? |
| [ 答案 72 ] |
用1.5g X (MMA2260D) or Z (MMA1260D) or X-Y (MMA6260Q).
|
| [ 问题 73 ] |
假设我要测量汽车的速度, 我是直接通过检测轮速更快还是用加速度传感器测量再进行积分运算快呢? |
| [ 答案 73 ] |
最简单的还是直接通过检测轮速。
|
| [ 问题 74 ] |
飞思卡尔加速传感器的主要性能和使用优点? |
| [ 答案 74 ] |
请在以网站选择和回看已存档的飞思卡尔加速传感器在线座谈:http://www.freescale.com.cn/webcast/Sensors/MMA7260Q.asp
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| [ 问题 75 ] |
加速计传感器在市场上的竞争对手如何?请在技术和价格方面谈谈现在的状况。
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| [ 答案 75 ] |
目前三轴的传感器市面上有飞思卡尔外, 尚有欧系及日系的产品, 其规格上有灵敏度, 省电功能及 IC size 大小上有些不同, 价格上也会随着产品的规格, 各公司的产业规模及产品上市的时间点, 有所不同。
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| [ 问题 76 ] |
我以前未用过这种单片机, 哪位知道哪里能下载到中文资料或哪里能买到教材 (关于 MC68H***)? |
| [ 答案 76 ] |
您可以下网站下载到中文资料:
MC68HCXX: http://www.freescale.com.cn/products/8bit/8BitMCU_download.asp
传感器: http://www.freescale.com.cn/Products/sensors.asp
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| [ 问题 77 ] |
飞思卡尔的传感器主要涉及哪些领域，传感器开发的前景怎么样，发展方向是什么? |
| [ 答案 77 ] |
主要有压力传感, 惯性传感及相关安全侦察 IC, 传感器已渐渐普及到一般消费性产品的应用, 尤其是手持式产品, 在这一领域将会有很高的年复合成长率。
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| [ 问题 78 ] |
请问加速传感器的应用场合，能否用在汽车控制领域? |
| [ 答案 78 ] |
Yes, it can use to detect shock in air-bag system, roll-over warning & safety control, …etc. Now many customers use it on car alarm or GPS INS application.
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| [ 问题 79 ] |
与单向的相比，X-Y 双向的加速度传感器在汽车上有什么特别用途? |
| [ 答案 79 ] |
The low g sensor with XY axes detection can provide car tilt status on the road plane. So it can use in car alarm and car event recorder application.
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| [ 问题 80 ] |
是否可应用在安防产品上? |
| [ 答案 80 ] |
Yes, the low g sensor can use to detect tilt angle, movement, shock and vibration. And it provides higher reliability and lower power consumption, compared with traditional mechanical sensor.
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| [ 问题 81 ] |
可否提供免费样片 3 个和应用资料? |
| [ 答案 81 ] |
MMA7620Q 应用资料: http://www.freescale.com.cn/Products/sensors/MMA7260Q.asp
你可在飞思卡尔网站免费申请样品
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| [ 问题 82 ] |
和陀螺仪是不是一种产品? |
| [ 答案 82 ] |
功能上两者相似, 但加速计传感对非旋转的运动有较佳的侦测, 陀螺仪则对旋转的运动侦测, 有较好的反应。
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| [ 问题 83 ] |
精度超小型 3 轴加速传感器是干什么用的，主要用于什么地方? |
| [ 答案 83 ] |
It provides 3-axes acceleration and tilt-angle detection. Many consumer electronics system will use it to achieve menu-scrolling, HDD freefall detection, power-saving or stolen alarm, game-pad tilt control…etc.
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| [ 问题 84 ] |
您好，可否使用加速度传感器做一个旅程表?且使用普通8位处理器? |
| [ 答案 84 ] |
No, the precise dead reckoning application needs powerful processor to handle complicated calculation to achieve car position application. So 8-bit MCU is not able to handle the calculation effort.
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| [ 问题 85 ] |
您能详细介绍基本原理吗 G 单元－积分器－采样保持－放大滤波前三步都完成什么作用?还有那一步完成C－V变换? |
| [ 答案 85 ] |
sample & hold
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