年紀已經可以稱"老",就有一些老心情要說一說,否則就忘了。

2011年7月26日 星期二

5V LDO 電路 (7805)

這是由網路找到的。
The best regulators for using in electronic projects are the 78LXX (78L05, 78L09, 78L12, 78L15 … ). I searched google for the application notes and I found them easily (look in the bottom part of the page for the download link).

Their typical application was the IC + 2 small condensers (the input is at 0.33uF and the output is at 0.01uF), but after some tryouts and more googling I found this page which, too be honest with you, I consider it to be the best circuit over the web.
I tested the circuit and it worked like charmed.
Reading the application note we see that the input voltage must be between 7V and 20V and the output voltage is between 4.75V – 5.25V .

IC1 = 78L05 / 78M05 / 7805 (差異:0.1A/0.5A/1.0A。當然,7805靜態功率較大)
78L05.GIF
所需元件
  • D1 = 1N4007
  • C1 = 100uF
  • C2 = 10uF