主题:轮胎压力监控系统(TPMS)和飞思卡尔TPMS解决方案 |
在线问答: |
[问:yejing] |
天线制作方面应该注意的哪些问题?采用印制天线和螺旋天线的优缺点是?
MC68HC908RF温度范围能够达到轮胎内部的要求吗? |
[答:飞思卡尔] |
天线制作方面应该注意的哪些问题在跟著的Presentation 有题到. 印制天线的优点是不用Cost,但功率低.螺旋天线功率高但占空间多.
RF2 的可工作温度是-40 - +125. |
[2005-6-30 10:26:58] |
[主持人:ChinaECNet] |
各位听众(网友),上午好!欢迎参加中电网在线座谈。今天,我们有幸邀请到Freescale公司的专家就""举行在线座谈。在座谈中,您可就您关心的问题与Freescale公司的专家在线进行直接、实时的对话交流。中电网衷心希望通过大家的共同努力,不仅能够增进各位听众(网友)对轮胎压力监控系统(TPMS)和飞思卡尔TPMS解决方案的了解和掌握,而且能够为大家事业的发展带来裨益。 |
[2005-6-30 10:32:29] |
[问:charlie22] |
使用Freescale的TPMS方案,在通讯的时候发现问题:
1)发射10字节数据包(包括Pre+ID+HEADER,计两字节),接收有效数据应该为8字节,但有时候会接收到9字节或10字节;
2)漏包较多,即平均2分钟左右才能收到一个数据包; |
[答:飞思卡尔] |
1 请检查33594的设置,例如CR2的值应和发送端的一致。仔细对比收到的9或10字节中多出的是什么部分,检查发送端的发送程序和接收端的接收程序,然后分析原因。
2 发送的间隔是多少,3秒还是...?发送和接收的环境是什么?硬件设计,程序控制流程,使用环境,都有可能导致漏包。 |
[2005-6-30 10:33:27] |
[主持人:ChinaECNet] |
我们已经进入问答阶段如果听众想重温演讲或内容可以点击下面“回顾演示”重看演讲。 |
[2005-6-30 10:34:28] |
[主持人:ChinaECNet] |
在此回答问题的专家是Freescale公司的:Harvey Wong,Helen Lu,Norman Chan,WS
Wong,Robin Ma,YK Wong和Harriet Mak。 |
[2005-6-30 10:34:58] |
[问:qddyf] |
现在我正在试验tpms系统。但是我总是不能初始化MC33594。不知道怎样知道mc33594是否已经正常工作了?我测试晶振已经起振了。 |
[答:飞思卡尔] |
若MC33594工作在发射占便会有信号产生 |
[2005-6-30 10:35:40] |
[问:] |
1. 请问Freescale何时能提供具有LF双向传输功能的TPMS solution
2. 请问Freescale何时会推出下一代的TPMS solution |
[答:飞思卡尔] |
Freescale next generation solution has RF,2CLF,8 bit MCU, Temp/Pressure
sensor all function on chip.
-Low-power, 8-bit MCU with in-situ programmability
-512b RAM, 8Kb Flash, and 32 parameter registers
-Pressure, temperature, voltage measurements
-6 channel, 10-bit analog-to-digital converter
-Internal 315/434 MHz RF transmitter
-ASK/FSK modulation with range of data rates
-2-channel LF input with detector / decoder
-Piezoelectric or external accelerometer motion sensor, detectors, and
decoder
Sample in Sep. 2005 and production in 2006. |
[2005-6-30 10:35:57] |
[问:YZMYJ] |
如何保证整机的低功耗和抗干扰性? |
[答:飞思卡尔] |
All this depends on the algorithm used. You need to decide on saving
battery life in driving and parking mode. Some countries do not make transmissiom
in park mode whilst others do so once every 30mins. For anti-jamming,
the Tire 32 bit IDs allows designed recognition. If corrupted data is
received, the Rx will ignore this. |
[2005-6-30 10:37:30] |
[问:YZMYJ] |
轮胎压力监控系统(TPMS)和飞思卡尔TPMS解决方案的成本怎样? |
[答:飞思卡尔] |
Please inquire price through Freescale local sales office or distributor.
The cost depent on the production year and purchasing quantity. |
[2005-6-30 10:37:54] |
[问:jobbobo] |
请介绍一下在TPMS系统中声表面波(SAW)器件的应用前景!谢谢! |
[答:飞思卡尔] |
Freescale solution does not include SAW. |
[2005-6-30 10:38:26] |
[主持人:ChinaECNet] |
我们已经进入问答阶段如果听众想重温演讲或内容可以点击下面“回顾演示”重看演讲。 |
[2005-6-30 10:41:49] |
[问:qianwei920] |
freescale的demo板,rf2,33594的晶振测试xtal1引脚看不出振荡,rf2的dataclk脚能看出振荡但幅度很小,只有0.4v,而33594的mixout看不出有很好的波形。这样正常吗? |
[答:飞思卡尔] |
测量的工具是示波器吗?
RF2,33594的xtal1引脚上的振荡波形输出是30秒左右发送一次因此请参考您的示波器功能是否可以捕捉波形,dataclk的波形应该是3v左右的。mixout的波形最好使用频谱仪观察。 |
[2005-6-30 10:41:57] |
[问:ivanjin] |
请问,这次飞思卡尔提出的方案与去年的M8020系列有什么不同,集成RF的MCU加M8020X。
2。目前对于GE.INFIEON的NPX2和SP30的产品。贵公司有更好的产品吗?对于这两个竞争产品贵公司如何评价呢?
3。GE和INFION的开发平台可以共用。对于用和的选择度可以提高。同时很容易替换的。请问你的平台如何建立和推向市场呢? |
[答:飞思卡尔] |
FSL next gen solution will be RF+MCU+sensor+LF on one chip
integration. |
[2005-6-30 10:42:57] |
[问:zhaohongzheng] |
● 接收器是否显示每个轮胎的气压,还是只显示告警的低气压?轮胎模块可以检查出低气压阈值,其使用的能量要少于获得完整的8位值所需的能量。
● 气压和温度的测量频率是多少? |
[答:飞思卡尔] |
Normally, Pressure is measured more frequent than temperature. Some
countries will take one measurement every 3s and after 10 readings, it
is then transmited. So this is once every 30s unless large change in measurement
is seen. The transmit will take the most power, then the presure measurement,
then the temperature measurement. |
[2005-6-30 10:43:29] |
[问:libingqiang] |
我想实现双向通讯,请问专家有什么好的方案 |
[答:飞思卡尔] |
使用低功耗的双向RF收发模块完成信息传递。相关的器件可以从有关的公司获得。 |
[2005-6-30 10:44:13] |
[问:kevinlee] |
有没有不用LED,而用LCD的方案,从而可以以图象的方式来显示?这样需要做什么改动呢? |
[答:Harvey] |
can use a FSL MCU which supports SPI and LCD display. |
[2005-6-30 10:44:34] |
[问:zhaohongzheng] |
● 数据发送的频率是多少?
● 每个数据帧中有多少位?发射器要比其他任何部分更快地消耗电池能量,因此经常传输较短的数据帧通常有助于延长电池寿命。
● 气压降低会出现什么现象?为了确保在任何恶劣的环境下都能使数据到达接收器,轮胎模块应可以多次发送告警信号。 |
[答:飞思卡尔] |
数据发送的频率(Data rate?)是9.6kbps for FSK
请参考Freescale application note AN1951
气压降低会令轮呔跟地面的friction加大,而热力增加令呔有危险. |
[2005-6-30 10:45:04] |
[问:zbs8898] |
请问飞思卡尔轮胎压力监控系统(TPMS)解决方案优势在哪里? |
[答:飞思卡尔] |
1st gen Daytona solution has better flexibility for after market. No
extra cost for LF wiring and low power consuption. |
[2005-6-30 10:46:07] |
[问:magn] |
为什么hc908rf2发送和MC33594接收所使用的晶振频率不一样,必须使用AN1951.PDF所推荐的晶振(为13.56和13.580625)么? |
[答:飞思卡尔] |
请看他们的数据手册,PLL分频器的不同比例决定的。 |
[2005-6-30 10:47:10] |
[问:charlie22] |
1,MC33594 "ID Byte" 和 "Tone" Detection 的异同点是什么?如何配置和切换种模式? |
[答:飞思卡尔] |
I am not sure why you are asking tone detection because TPMS only use
FSK or ASK modulated means (Manchester coding). The ID byte can be set
inthe configuration register. |
[2005-6-30 10:48:35] |
[问:zhaohongzheng] |
轮胎模块中各个电阻及电容的作用以及具体数值是如何确定和计算的!谢谢!!! |
[答:飞思卡尔] |
问题比较笼统,一般来讲,硬件开发的经验和所使用的器件的数据手册和应用指南等可以帮助您理解和构建您的电路。 |
[2005-6-30 10:49:21] |
[问:libingqiang] |
MC33493靠调节晶振的负载电容来调节发射频率,请问当CFSK内部接通和关断时,负载电容分别是怎样计算的。以串行连接为例吧 |
[答:飞思卡尔] |
This highly depend on the crystal loading and PCB board stray capacitance
in your design. From our past experience, we suggest you reference to
our data sheet recommend crystal loading value. Then fine tune your loading
cap by direct measuring. |
[2005-6-30 10:51:39] |
[问:huxinhappy] |
车辆多时,干扰如何解决 |
[答:飞思卡尔] |
A 32 bit ID gives 4.294.967.296 different combination. The probability
to get the same ID on the same car or between 2 cars close enough is almost
non existant. Some suppliers have organized the 32 bit in "sub" IDs. The
first 4 bit are for example to identify the sensor supplier; some other
one the end customer identification, some other one the manufacturing
plant, date code etc
By doing a learning phase. At first, when the receiver is started up it
listens to the wheel and is recording the ID transmitted by the tire and
so it knows which is which tire.
Anyway, it is true that the Receiver can receiver some other car’s RF
signal but it should ignore this given that the ID is not matched.
|
[2005-6-30 10:52:08] |
[问:HAPYHU] |
有不有关于TPMS的软件包!包括接受模块发射模块的控制程序? |
[答:飞思卡尔] |
Yes we do, but you need to modify it to comply with your country"s regulation
and law. Pls visit our Freescale website and obtain this tools. |
[2005-6-30 10:53:23] |
[问:Wilson Wu] |
我们现时用mcu是mc68hc908rf2,但在试产时发现晶体13.56mhz有停振及不稳定现象,请问对晶体有那些重要要求吗?另外,在资料上的参考线路无法显示其负载电容在那里,及连接cfsk脚的电容应多大为合适? |
[答:飞思卡尔] |
选择质量可靠的晶体是减少故障的保证。
其次,参考电路的电容值已经给出。请看AN1951文件中,C5=27pf。
由于不同的晶体的特性可能不同,请参考数据手册上的推荐晶体的指标。 |
[2005-6-30 10:53:39] |
[问:uvw123] |
你们所采用的低频唤醒能传输多远?天线采用什么样的形式?具体的型号?单端天线还是线圈那种形式?比如匝数,电感量大小等。如何和电容相匹配?发射端和接收端有什么不同之处? |
[答:飞思卡尔] |
今天我们讨论的方案未有加上低频唤醒传输function |
[2005-6-30 10:54:04] |
[问:Shailesh] |
Can the system detect the sensor module correctly
after initialisation if the Tyre is changed for e.g Front Left Tyre put
at back Right while servicing of Car? |
[答:飞思卡尔] |
A learning phase must be performed each time with a special sequence. |
[2005-6-30 10:54:42] |
[问:dlp145] |
无线传输的频率是非颠倒15/434MHZ 调频调幅,这样会对车载电视产生扰吗 |
[答:飞思卡尔] |
设计合理的产品是不会对车载电视产生干扰的。 |
[2005-6-30 10:54:58] |
[问:charlie22] |
MC33594 "ID Byte" 和 "Tone" Detection 的异同点是什么?如何配置和切换种模式? |
[答:飞思卡尔] |
I am not sure why you are asking tone detcetion because TPMS only use
FSK or ASK modulated means (Manchester coding). The ID byte can be set
inthe configuration register. |
[2005-6-30 10:55:47] |
[问:] |
请问的DEMO Board的原始程序是用什么软件开发的? 我用CW3.0 &
CW3.1都不能直接compiler |
[答:飞思卡尔] |
是用P&E公司的编译工具 |
[2005-6-30 10:58:41] |
[问:Wilson Wu] |
hi,我想请问RF天线问题,在轮胎里的发射器采用那类型天线会最好。 |
[答:飞思卡尔] |
Normally, we use PCB board antenna or loop coil antenna. PCb antenna
without cost,but to design a good efficiency PCB antenna is very difficult.
If you want to have better performance and easy to design, it is better
to use loop coil antenna. |
[2005-6-30 10:59:00] |
[问:shanya] |
可以提供RF2的发射天线制作方案吗?如果用环形铜箔作天线的话,会被轮毂屏蔽掉. |
[答:飞思卡尔] |
请参考我们application note AN1951 |
[2005-6-30 11:00:13] |
[问:ganjianqin] |
专家你好!
1.MPXY8020在车辆静止的时候也会定时来测量压力,但对于这个对功耗非常敏感的系统来说,是绝对不允许的,请问专家该如何解决这一问题!谢谢!
2.在TPMS的应用笔记中发射机用的是印刷线路板天线,专家是否可以提供它的设计方法。
3.可以告知此套系统大概一套(4个发射机+1个接收机)的成本价。 |
[答:飞思卡尔] |
You can use system design when the sensor start to test. Some customer"s
design testing start when speed up to 40km/hr. Some customer"s design
testing start when speed up to 25km/hr. |
[2005-6-30 11:01:22] |
[问:rglist] |
根据你方提供的方案在实际的接收中,其发射距离很短,有无何种可行的措施解决? |
[答:飞思卡尔] |
检查硬件的设计,走线等等,
改善发射天线的设计以及安装位置
提高接收的灵敏度,增加PA,天线的安装位置等等。 |
[2005-6-30 11:01:24] |
[问:charlie22] |
当Remo2的ID设置为0xB8, Tango3通过tone方式(联系的"1")来唤醒Remo2,实际发现丢包率比较高 |
[答:飞思卡尔] |
Are you setting 0xB8 in the preamble? If so then I see no problem with
this.
It is likely that your RF communication like is vulunerable to noise and
attentuation. Another possibility is that the clock signals are not setup
sufficiently. You need to allow at least 2ms for data clock before transmission. |
[2005-6-30 11:02:03] |
[问:shanya] |
908RF2军用级的工作温度范围是---40-125℃,为什么我们测试的时候到100度就不能工作了? |
[答:飞思卡尔] |
Please contact local Freescale sales office or distributor who you purchased
the chip for root cause investigation. |
[2005-6-30 11:02:52] |
[主持人:ChinaECNet] |
各位观众,现在用户提问很踊跃,专家正在逐一回答。请耐心等待您问题的答案,同一问题请不要多次提交。 |
[2005-6-30 11:03:45] |
[问:shanya] |
33594前面要不要加声表面滤波器?不加会有什么影响? |
[答:飞思卡尔] |
一般情况33594前面可不用加声表面滤波器, 因为左前级加上滤波器可以滤去noise但同时也会增加 noise figure of whole
system. |
[2005-6-30 11:04:51] |
[问:honghui525] |
请问Freescale提供的解决方案的功耗在多少的范围内?主控MCU的寿命会受哪些因素的影响? |
[答:飞思卡尔] |
功耗的影响因素很多,如工作环境的温度,软件工作流程等等。
可以利用我们每个器件的工作电流(在数据手册上有详细的指标)来从理论上计算,然后和您实际在一定时间测量的数据进行比较获得比较接近真实的应用工作功耗的指标。 |
[2005-6-30 11:05:26] |
[问:Seraphy] |
如果我公司希望直接集成贵公司现有的demo模块是否可行,比如直接从串口读取所需数据?另外demo模块的PCB图和源代码能否开放? |
[答:飞思卡尔] |
The demo is include source code. But you the code does not allow you
integrate directly. It only allow you review the code and understand how
it programed. If you read the data directly, you may see some error as
it"s designed so. |
[2005-6-30 11:06:19] |
[问:qianwei920] |
freescale有没有下一代无电池的方案? |
[答:飞思卡尔] |
It is on road map. |
[2005-6-30 11:06:35] |
[问:davidjoe77] |
请问FREESCALE的方案传感器模块在正常状态下即每3秒测量一次每30秒发送数据一次,平均功耗有多少? |
[答:飞思卡尔] |
I don"t have these data on hand but to give you an idea, the sensor
itself will consume the following:
Idle – supply current is 600nA,
Pressure measurement mode, consumes 1.5mA,
Both the temperature measurement and the output reading utilizes 500uA.
For transmitting, takes 17000uA.
The battery"s usage has around 50% taken by doing transimission.
To come up with a solid number you need to add these up and mark up say
20% more. |
[2005-6-30 11:07:37] |
[问:Wilson Wu] |
经了解,外面现时的产品在车速超过140KM/小时,信息接收不可靠,怎避免这问题发生? |
[答:飞思卡尔] |
只要RF电路做得好(没有接收盲点),信息接收在车速超过140KM/小时,应可靠. |
[2005-6-30 11:07:54] |
[问:yhonghua2002] |
目前infineon和GE都推出了比较新的产品,freescale最近还有更新的sensor推出吗?谢谢! |
[答:飞思卡尔] |
Yes. Nest Gen product RF+MCU+Sensor+LF in one chip. Sample in Q4"2005.
Production in 2006. |
[2005-6-30 11:08:05] |
[问:sqsensor] |
您好,请问贵公司在TPMS中的压力传感器为什么不选用硅压阻式的?选择电容式的理由是什么?硅压阻的体积会比较小,灵敏度和成本较低。贵公司的电路部分是否适合硅压阻的传感器?谢谢 |
[答:飞思卡尔] |
Our sensor use CMOS technology. CMOS sensor power consumption is lower.
For such battery operation application. Power consumption is critical. |
[2005-6-30 11:09:25] |
[问:nannar] |
在接收模块使用GP32的过程中,对SPI中断的调试中,应注意哪些问题! |
[答:飞思卡尔] |
SPI的时序图可能对您有很好的帮助,有关的信号/CS, CLK,MISO,MOSI等等的波形时序要求。仔细定义信号的格式。请看GP32手册中有关的章节。
中断调试的要求和其它中断相似。 |
[2005-6-30 11:09:32] |
[主持人:ChinaECNet] |
各位观众,现在用户提问很踊跃,专家正在逐一回答。请耐心等待您问题的答案,同一问题请不要多次提交。 |
[2005-6-30 11:10:32] |
[问:davidjoe77] |
FREESCALE传感器/发射器模块平均功耗有多少uA? |
[答:飞思卡尔] |
For Tx sleep mode, it is 0.005uA, transmit mode is 17000uA
For Rx stop mode is 0.1uA, wait mode 1000uA, and run mode is 3000uA
For Sensor:
Idle – supply current is 600nA,
Pressure measurement mode, consumes 1.5mA,
Both the temperature measurement and the output reading utilizes 500uA.
For transmitting, takes 17000uA.
The battery"s usage has around 50% taken by doing transimission.
To come up with a solid number you need to add these up and mark up say
20% more.
But total power usage would depend on your algorithm. |
[2005-6-30 11:11:14] |
[问:ivanjin] |
4.目前TPMS的产品,在高速情况下,接收效果都不是很好,请问如何提高可靠性呢?微型天线的设计参考,能否给予一些建议呢? |
[答:飞思卡尔] |
在高速情况下,接收效果都不好, 一般都是RF电路做得不好(有接收盲占).只要RF电路做得好,应没有这问题.
微型天线的设计,请参考Application note AN1951. |
[2005-6-30 11:11:53] |
[问:ivanjin] |
请问,对于目前的轮胎的环境恶劣,传感器的防水问题如何解决呢?使用中贵公司的MPXY8020在导气孔的地方有冷凝水,会发生读数突变的问题。 |
[答:飞思卡尔] |
To resolve this problem, module designer need to have some special design
on housing to prevent water drop.
1. sensor face outside to allow water drop leaving sensor when driving.
2. some housing design put a metal plate beside ssensor. When temp down,
the metal temp drop faster than sensor. Water drop will be on the metal
plate, not on sensor. |
[2005-6-30 11:14:18] |
[问:luoshi] |
通讯是单向的,如何解决冲突的问题 |
[答:飞思卡尔] |
因这通讯是单向的,解决冲突的问题只有用Time multiplex 方法.而每一个发射器应有自己的ID. |
[2005-6-30 11:14:48] |
[问:yhonghua2002] |
RF+MCU+SENSOR+LF的产品大概会在什么时候推出?什么时候可以提供产品样片?谢谢! |
[答:飞思卡尔] |
Sample in Q4"2005. Production in 2006. |
[2005-6-30 11:15:22] |
[问:sqsensor] |
您好,请问贵公司的TPMS系统和GE的TPMS系统的区别在哪里?优势和劣势在哪里?谢谢 |
[答:飞思卡尔] |
FSL now solution will have RF integrated on chip as well. |
[2005-6-30 11:16:08] |
[问:ruzhao3324] |
采用FREESCALE这个方案的话,我们需要做哪些工作,哪些是你们提供的,哪些是需要我们开发的? |
[答:飞思卡尔] |
我们提供的评估板套件,包括4个发射板和一个接收板,及其原程序代码(汇编指令)。请看AN1951.pdf文件。
使用到的飞思卡尔的芯片,开发工具,包括软件调试平台和硬件调试和编程工具,可以通过我们的销售渠道购买。
除了这些,都是您需要您完成的。 |
[2005-6-30 11:16:24] |
[问:thscales] |
射频发射卡的功率大约多少?加大发射功率对电池有多大影响 |
[答:飞思卡尔] |
射频发射卡的功率大约:0dBm
加大发射功率,电池的消耗会加大. |
[2005-6-30 11:16:54] |
[问:zhaohongzheng] |
● 是否需要对气压和温度两个参数都进行测量,还是其中一个参数的测量频率要高于另外一个?
● 是否需要温度补偿功能 (即,改变低压告警阈值作为温度的一个函数)?若需要,是在轮胎端还是在接收器端部署?轮胎模块执行计算的次数越多,电池寿命越短。
|
[答:飞思卡尔] |
temp and pressure is measured on separate times. Normally regulations
would mandate pressure requirement and not temp (I"m 100% sure on temp).
So people tend to take more measurements with pressure than temp. Our
temperature device has a positive coefficient and is calibrated at room
temp in factory. It is up to you if you want to do further temp compensation.
However, like i say, you need to check with your law and regulation, but
I do not know of anyone doing this. |
[2005-6-30 11:17:50] |
[问:harvest] |
飞尔的工程师,您好!我们采用贵公司的MPXY8020A和68HC908RF2方案做了个TPMS,在常温常压下温度值是00H~03H,压力值在60H附近。我的仿真软件用的是P&E
Micro 的ics08rkz.请问您能否帮我查找一下原因??谢谢了!!! |
[答:飞思卡尔] |
检查您的测量方式,软件方面注意流程,可以参考我们的评估板这部分软件,和8020A的测量方式。
在常温和常压下,应该测量到100KPa附近和25C左右的数值。 |
[2005-6-30 11:18:46] |
[问:nannar] |
请介绍一些低躁声放大器的型号! |
[答:飞思卡尔] |
在我们Freescale 的application note AN2719 有一个放大器的设计可参考. |
[2005-6-30 11:19:03] |
[问:juliguo] |
请问飞思卡尔轮胎压力监控系统(TPMS)的核心原理.能简单介绍一下吗? |
[答:Harvey] |
It is in the presentation. You can re-play it. |
[2005-6-30 11:19:38] |
[问:Wilson Wu] |
在轮胎的高压力中,关于压力方面的要求对电池及晶体有什么特殊要求吗? |
[答:飞思卡尔] |
You need to use good RF grade crystals.
Component specification should cover (eg. -40 to +125°C)
Component specification variation
Crystal: series resistance (increase with temp.), keep between 20 and
50 ohms.
Load cap of crystal keep to within 12pF maximum.
Else, both will increase the oscillator (data clk) settling time.
For battery, choose one that has enough Ampheres per hour, and it depends
on cost and your algorithm. You need at least 300mA.h |
[2005-6-30 11:21:30] |
[问:kevinlee] |
请问:有没有轮胎压力监控系统(TMPS)和 倒车测距预警 两个功能融合在一起的整套技术解决方案,即采用飞思卡尔的哪些芯片组。希望能得到全面的解答。
谢谢
我的Email:kevin_lee@zj.com |
[答:飞思卡尔] |
这个工作需要您自己完成。
倒车测距需要超声波等等感应方式或其它方式,我们暂时没有超声波感应芯片,但是可以和我们的单片机,比如您在TPMS接收端使用的融合成一体,节约成本。
根据具体的要求不同,您可以参考SG187.pdf文件来选择合适的单片机作为您的产品应用。 |
[2005-6-30 11:22:12] |
[问:meng_] |
请问大型车辆的TP-SENSOR 建议采用何种 |
[答:飞思卡尔] |
Depent on the pressure of the tyre. As you did not specific the tyre
pressure. You may check MPXY8040A spec. The pressure range can cover some
bus application. |
[2005-6-30 11:22:12] |
[问:ruzhao3324] |
为什么用电容式压力传感器,为什么不用应变片或压阻式? |
[答:飞思卡尔] |
PZ resistive can also work but it is more costly in power. Capacitive
is leading technology in this respect and you need to have many years
of running power for tires. |
[2005-6-30 11:23:01] |
[问:shanya] |
请问33594前面要用SAW吗,不用会有什么影响? |
[答:飞思卡尔] |
一般是不用加SAW, 原因请看以前我的答题 |
[2005-6-30 11:23:11] |
[问:sunny_liang] |
轮胎监测系统中的电池的使用寿命多久? |
[答:飞思卡尔] |
It is usual to consider 10 years and a bare minimum of 7years. |
[2005-6-30 11:24:04] |
[主持人:ChinaECNet] |
各位观众,现在用户提问很踊跃,专家正在逐一回答。请耐心等待您问题的答案,同一问题请不要多次提交。 |
[2005-6-30 11:24:05] |
[问:whwuhai] |
轮胎高速旋转时干扰或无线信号是怎样的?
有内胎的可以么?
电池寿命可靠么? |
[答:飞思卡尔] |
干扰来源很多,比如来自天线的方向性和地面的衰减和反射。
有内胎的轮胎不太适合安装。
电池的寿命决定于其自身的质量和使用的功耗。 |
[2005-6-30 11:24:57] |
[问:shanya] |
发射的匹配网络有怎么做?铜箔天线可能会被完全习屏蔽掉的? |
[答:飞思卡尔] |
发射的匹配网络请参考MC33493 data sheet page 13 或 application note AN2719 . |
[2005-6-30 11:25:39] |
[问:HAPYHU] |
与pc通讯的软件哪有?? |
[答:飞思卡尔] |
可以自己编写一个小的RS232程序和PC通讯。
我们的评估板使用的KX8串口程序在评估板中包含。 |
[2005-6-30 11:26:23] |
[问:kevinlee] |
你们的RS232和哪里的PC机连接,是指汽车里的吗? |
[答:飞思卡尔] |
在评估板套件中的应用程序是和普通电脑连接的。 |
[2005-6-30 11:27:01] |
[问:zlt7513] |
请问方案的功耗是多少,RF接收和发送的功耗,安装位置在什么地方,通信距离是多少,轮胎温度超过85度时,方案怎么解决,谢谢 |
[答:飞思卡尔] |
System power consumption depend on your system design, like how many
min. you read and transmit signal. transmition distance depend on you
antina design and tyre condition. MPXY8020A and 908RF2MFA operation temp
up to +125C |
[2005-6-30 11:27:50] |
[答:飞思卡尔] |
马先生在演讲中有提到目前TPMS有两份标准 – FMVSS 138 & ISO,请问到那里可以得到ISO的规格?
两份标准有何差异? |
[答:飞思卡尔] |
请访问它们的网站获得。前者是美国的标准,后者是国际标准。 |
[2005-6-30 11:28:11] |
[问:oneteng] |
抗干扰指标是多少?两车靠近是否会相互干扰 |
[答:飞思卡尔] |
因signal传送时间是很短很短,而且每个发射器有自己的ID,所以干扰是可以减低. |
[2005-6-30 11:28:35] |
[问:HAPYHU] |
请问发射模块能不能把它设计成在晚上停车的时候停止工作,或休眠啊? |
[答:飞思卡尔] |
可以通过其它辅助手段完成。
这些手段可以是软件完成,硬件完成,或两者结合完成。 |
[2005-6-30 11:29:05] |
[问:Deng] |
遥感模块和TPMS的通信是通过那种方式进行?是采用CAN或别的接口? |
[答:Harvey] |
SPI |
[2005-6-30 11:29:07] |
[问:yhonghua2002] |
freescale,目前有没有量程达到1400Kpa的传感器? |
[答:飞思卡尔] |
1400kPa sensor is not in production yet. |
[2005-6-30 11:29:23] |
[问:nannar] |
如果接收端加了LNA放大器后,有没有必要在放大器的前端加SAW! |
[答:飞思卡尔] |
没有必要 |
[2005-6-30 11:29:24] |
[问:Wilson Wu] |
mcu上所配的13.56m晶体有特别要求吗? |
[答:飞思卡尔] |
情看MCU手册上说明。 |
[2005-6-30 11:29:47] |
[问:shanya] |
RF匹配网络有推荐的电路吗? |
[答:飞思卡尔] |
发射请参考MC33493 data sheet
接收请参考application note AN2601 |
[2005-6-30 11:31:31] |
[问:davidjoe77] |
Freescale方案关于汽车的运动是怎么检测的? |
[答:飞思卡尔] |
可以通过气压变化的速率来检测汽车的运动,辅助于其它的硬件手段也可以达到。 |
[2005-6-30 11:31:32] |
[问:sqsensor] |
请问贵公司的传感器模块内好像没有集成加速度传感器?那么贵公司使用的是什么方式来控制系统何时开启工作?何时关闭工作? |
[答:飞思卡尔] |
We sensor has not G-switch integrated as the electronic G-switch bring
in high power consumption. Most Customers add in machenical g-switch in
their system as very low cost and power save. |
[2005-6-30 11:31:50] |
[问:HAPYHU] |
与pc机连接在PS上显示数据用的是什么软件,对每一款单片机都可以吗? |
[答:飞思卡尔] |
该软件仅针对TPMS评估板。 |
[2005-6-30 11:32:18] |
[问:yhonghua2002] |
有没有8020a的应用笔记可供下载 ?谢谢! |
[答:Harriet] |
MPXY80xx 和其他信息可在以下网站下载
http://www.freescale.com.cn/Applications
/automotive_tire.asp |
[2005-6-30 11:32:53] |
[问:qianwei920] |
请问低频的近场效应使得低频的通讯距离很短,这样每个轮胎附近要做个天线以实现低频通讯,这每个天线与低频发射之间怎么连接? |
[答:飞思卡尔] |
今天我们讨论的方厂案是没有低频通讯功能加上的. |
[2005-6-30 11:32:58] |
[问:sqsensor] |
用你们的电路系统配其它的传感器模块是否可以?比如传感器选用硅压阻的额?(内部集成包括压力传感器,温度传感器,加速度传感器) |
[答:飞思卡尔] |
如果您选择其它的传感器,请参考它们的使用要求来构建您的电路。 |
[2005-6-30 11:33:15] |
[问:Deng] |
据我们所知,TPMS解决方案有间接式和直接式两种,能介绍这两种方案的差异吗?那种方案较好? |
[答:飞思卡尔] |
在我们的讲座中提到了。
间接式是利用其它部件来计算的。
直接式是利用专门的部件来测量的,更准确,适应的范围大。 |
[2005-6-30 11:35:02] |
[问:Deng] |
遥感模块能否进行在应用中编程(IAP)? |
[答:飞思卡尔] |
不能 |
[2005-6-30 11:35:31] |
[问:ys3663391] |
我感觉TPMS系统只能应用在特定的汽车里。因为如果我的汽车如果没用TPMS系统,如果我需要这种功能,我的汽车从轮胎到汽车电子系统是否需要完全进行更换?如果是,我认为他会限制TPMS系统的市场推广,谢谢! |
[答:飞思卡尔] |
In China, many TPMS module makers provide after market solution. If
you choose to install those solution, you will no need to change tyre
and elctronic system. They can add module to your rim or change valve.
Of cause, there will be a additional electronic system to install in you
card for TPMS. |
[2005-6-30 11:35:34] |
[问:gsm504004] |
请再介绍一下台压检测原理 |
[答:飞思卡尔] |
请看我们的AN1951.pdf文件 |
[2005-6-30 11:35:54] |
[问:zhngjnpng911] |
远程轮胎压力监测模块的整体电源管理十分重要,Freescale采用了那些解决方案? |
[答:飞思卡尔] |
我们使用的传感器和单片机(MPXY8020/40和RF2)都是低功耗的,从而在根本上保证了产品的低功耗。多种工作模式,灵活应用可以到达节电的目的。 |
[2005-6-30 11:38:22] |
[问:kevinlee] |
评估板或实验板,我可以从哪里获得?
郑州是否有代理商? |
[答:飞思卡尔] |
郑州有我们的代理。请访问我们的中文网站http://www.freescale.com.cn获得联系方式。 |
[2005-6-30 11:39:57] |
[主持人:ChinaECNet] |
所有问题均已提交给Freescale公司的专家。座谈期间未回答的问题,Freescale公司专家也会逐一回答,并在中电网上公布,请大家注意收看。 |
[2005-6-30 11:40:35] |
[问:ivanjin] |
请问,在150KM/H下,RF盲点具体指什么呢?与通讯协议,编码方式有关吗。还是RF的天线不匹配。 |
[答:飞思卡尔] |
RF盲点是指在轮呔转动时有些位置是接收不到的.这是RF的问题,像天线. 因每一个编码信号侍送是需要一定的时阎,若在这时阎内收不到信号通信便有问题,高速时这机会增加. |
[2005-6-30 11:42:23] |
[问:zhaohongzheng] |
轮胎模块的具体安装位置?以及压力和温度传感器具体采集压力和温度数据的过程?谢谢!!! |
[答:飞思卡尔] |
The sensing module is mounted inside the rim or valve stem of the wheel.
Essential an internal 8bit register is used to perform the A/D function
in the sensor module. A digital output is provided, you need to shift
them out. For pressure, the internal P cell performs the sensing of the
pressure in terms of capacitance and this is converted to voltage. It
is compared to an internal 8 bit register.
There is also a current source that provides a voltage with the diffused
resitor which gives a reading of the temperature. This is also
shifted out when selected.
An on board timer (outputs a low every 3s) is used to signify the MCU
for capturing of the digital output which can be either temp or pressure
depending on the selection bits S0 and S1.
To know how to perform pressure/temp measurement pls refer to our app
notes AN1954 and 8020 data sheet. |
[2005-6-30 11:43:48] |
[问:renmingcan] |
飞思卡尔应用的是低功耗工艺,但是与SAW相比,又没有什么有点? |
[答:飞思卡尔] |
请你具体多说一次问题 |
[2005-6-30 11:44:42] |
[问:rglist] |
根据你们的DEMO方案在实际发射中,因轮毂屏蔽作用实际发射距离很短,除了螺旋天线,是否有其他的具体的解决方案可提供参考 |
[答:飞思卡尔] |
请参考MC33493 data sheet 或Application Note AN2719 |
[2005-6-30 11:45:47] |
[问:lionel_lau] |
请问如何解决RF2发射pll锁定慢?正常1ms,部分晶振要〉50ms才有212kHz
clock output |
[答:飞思卡尔] |
请参考您使用的晶体参数是否合适,一般正常是在1.5ms之内可以完成锁定的。
推荐的晶体参数指标可以在RF数据手册上PLL有关章节得到。 |
[2005-6-30 11:46:08] |
[答:飞思卡尔] |
目前在某些角度会收到不到讯号,请问要如何避免RF死角? |
[答:飞思卡尔] |
Use antenna with better radiation pattern,
Good matching. |
[2005-6-30 11:47:29] |
[问:ivanjin] |
请问对于天线的匹配,通过耦合来测量的标准是什么呢? |
[答:飞思卡尔] |
We are now using the S-parameter by the Network Analyzer. |
[2005-6-30 11:48:49] |
[主持人:ChinaECNet] |
由于时间关系,本次中电网“在线座谈”马上就要结束了。虽然各位听众(网友)已与Freescale公司的专家讨论了许多问题,但是还有许多提问没有来得及进行交流。本次在线座谈结束后,中电网将请Freescale公司的专家继续答复所有的来自各位听众(网友)的提问,然后整理上载到中电网网站上,以便大家查阅。 |
[2005-6-30 11:48:54] |
[问:bill_xie] |
如何确定不同厂家、不同使用年限的车胎的胎压的安全范围? |
[答:飞思卡尔] |
You will get the data when you purchase tyre. You may also get data
from tyre maker web. |
[2005-6-30 11:49:04] |
[主持人:ChinaECNet] |
恭喜您, 温州市盛博电子有限公司的shanya经过电脑抽奖您在本次座谈中获得一部MP3播放器。请网名为shanya的用户与中电网联系(8610-82888222-7008
或 lilin@chinaecnet.com)。 |
[2005-6-30 11:49:05] |
[主持人:ChinaECNet] |
在此,中电网特别感谢给予本次中电网在线座谈巨大支持的Freescale公司,特别感谢专门在线回答各位听众(网友)提问的Freescale公司的各位专家们,特别感谢各位听众(网友)积极热情的参与。 |
[2005-6-30 11:49:15] |
[问:qianwei920] |
您前面有提到接收模块使用mc9s12dp256,现在有这款mcu的例程供学习参考吗?用到mc9s12单片机是不是将其他汽车电子模块一起构建一个比较庞大的集成系统? |
[答:飞思卡尔] |
这是和其它功能结合的一个参考。目前暂时没有例程。 |
[2005-6-30 11:49:17] |
[问:qianwei920] |
目前Daytona的压力及温度值都是用8 bits的数值来代表,请问在新一代的solution中会用多少bits的数值来代表?精密度有没有提高? |
[答:飞思卡尔] |
Please wait for new solution datasheet. |
[2005-6-30 11:50:05] |
[问:zhgh0325] |
RF电路如何实现? |
[答:飞思卡尔] |
发射请参考MC33493 data sheet 或 application note AN2719
接收请参考AN2610 或 AN2830 |
[2005-6-30 11:51:05] |
[主持人:ChinaECNet] |
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[2005-6-30 11:51:39] |
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