飛思卡爾輪胎壓力監(jiān)控系統(tǒng)(TPMS) 在線座談問題解答(16)
[ 問題 116 ] 車輛多時,干擾如何解決
[ 答案 116 ] 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 exampl
[ 問題 117 ] 通訊是單向的,如何解決沖突的問題
[ 答案 117 ] 因這通訊是單向的,解決沖突的問題只有用Time multiplex 方法.而每一個發(fā)射器應有自己的ID.
[ 問題 118 ] hi,我想請問RF天線問題,在輪胎里的發(fā)射器采用那類型天線會最好。
[ 答案 118 ] 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.
[ 問題 119 ] 在輪胎的高壓力中,關于壓力方面的要求對電池及晶體有什么特殊要求嗎?
[ 答案 119 ] You need to use good RF grade crystals. Component specification should cover (eg. -40 to +125°C)Component specification variationCrystal: series resistance (increase with temp.), keep between 20 and 50 ohms.Load cap of crystal keep
[ 問題 120 ] mcu上所配的13.56m晶體有特別要求嗎?
[ 答案 120 ] 情看MCU手冊上說明。