2011年2月23日 星期三

最猛太陽風暴

近十年來最大太陽風暴襲擊地球
2012/1/26
一起自2003年十月以來,最強烈的太陽風暴這幾天影響地球,各相關機構都在密切注意,各大航空公司也視情況決定是否改變航線。

美國國家海洋暨大氣管理局表示,由於太陽質子密度增強,因此管理局會對航空公司、人造衛星及相關產業發布警訊。而各大航空公司也將根據美國海洋大氣管理局公布的數據,調整班機航線。

2011年2月20日 星期日

為DC/DC轉換器選擇正確的電感器與電容器

為DC/DC轉換器選擇正確的電感器與電容器 

隨著便攜式電子產品的體積在不斷縮小,其複雜性同時也在相應的提高。這使得設計工程師麵臨的問題越來越多,如電池使用壽命、占板空間、散熱或功耗等。本文以德州儀器TPS6220x係列降壓穩壓器為例,向設計工程師介紹在權衡解決方案的占用空間、性能以及成本時,如何為轉換器選擇正確的與。
  隨著手機、PDA以及其它便攜式電子產品在不斷小型化,其複雜性同時也在相應提高,這使設計工程師麵臨的問題越來越多,如電池使用壽命、占板空間、散熱或功耗等。

  使用DC/DC轉換器主要是為了提高效率。很多設計都要求將電池電壓轉換成較低的供電電壓,盡管采用線性穩壓器即可實現這一轉換,但它並不能達到基於開關穩壓器設計的高效率。本文將介紹設計工程師在權衡解決方案的占用空間、性能以及成本時必須要麵對的常見問題。

2011年2月18日 星期五

Pads 2005 教學(含pads logical 和pads PCB)

包含下列課程
Pads 2005
chap 0 pads  layout 概論
pads 2005 八小時課程 01-19(19部影片)
pads layout


2011年2月10日 星期四

MSP430 16-bit Microcontroller Code Examples and Function Library

MSP430 16-bit Microcontroller Code Examples and Function Library

     Code examples are available for every MSP430 device that configures each of the integrated peripherals for various application needs. Each zip file below includes both C and assembly code examples that can be directly imported into IAR or CCS. Developers may use the code examples "as-is" or modify the various code modules to jumpstart custom applications. Check the readme to see the complete list of available code snippets along with brief descriptions. Please read applicable section under terms of use prior to utilizing any software. Happy coding!

2011年2月9日 星期三

Parallel Port Pic Programmer for ICSP (Printer port 界面PIC燒錄器)

Parallel Port Pic Programmer for ICSP

My faithful programmer bit the dust, so I needed a programmer to work with my  system. I do not have USB on this machine, so the simplest way to go was to build what was needed. This is the result of that very specific need. I do not need to program anything that is not in the 16F family and all my projects are designed to use ICSP. I had all the parts on hand, left over from a "No Parts Pic Programmer" from many years ago.

Serial Port PIC Programmer (PIC 串列埠燒錄器)

Serial Port PIC Programmer  
 

The PIC programmer presented here uses PC's serial port for communication between the programming software and simple PIC programmer hardware.

Here is the list of currently supported flash devices from Microchip PICmicro 12F and 16F product lines: 12F629, 12F675, 16F627, 16F627A, 16F628, 16F628A, 16F630, 16F648A, 16F676, 16F72, 16F73, 16F74, 16F76, 16F77, 16F737, 16F747, 16F767, 16F777, 16F83, 16F84, 16F84A, 16F87, 16F88, 16F818, 16F819, 16F870, 16F871, 16F872, 16F873, 16F873A, 16F874, 16F874A, 16F876, 16F876A, 16F877 and 16F877A.

2011年2月4日 星期五

SMD 電阻 電容 電感 marking code

How to calculate the value of an SMD resistor

Most chip resistors are marked with a 3-digit or 4-digit code -- the numerical equivalent of the familiar color code for through-hole components. Recently, a new coding system (the EIA-96) has appeared on precision SMDs.

The 3-digit code

Standard-tolerance SMD resistors are marked with a simple 3-digit code. The first two numbers will indicate the significant digits, and the third will be the multiplier, telling you the power of ten to which the two significant digits must be multiplied (or how many zeros to add). Resistances of less than 10 ohms do not have a multiplier, the letter 'R' is used instead to indicate the position of the decimal point.

3-digit code examples:
220 = 22 × 100 (1) = 22Ω (not 220Ω!)
471 = 47 × 101 (10) = 470Ω
102 = 10 × 102 (100) = 1000Ω or 1kΩ
3R3 = 3.3Ω

more 3-digit SMD resistor examples...

2011年2月1日 星期二

徹夜用省電燈泡 當心罹乳癌

     徹夜開燈與罹患乳癌的關聯早在十餘年前已被發現,但以色列海法大學生物學教授海姆近期研究指出,開燈睡覺者罹患乳癌的機率,比沒有開燈者高出22%。這項數據比之前的研究高出甚多,究其原因,他認為是人們逐漸換用省電燈泡所致。