Dear CAT sir,
Please don’t mind as I just add some remarks. (我只是過路一提,請不要介意) It is a basic electronics that: Under no loading condition, it is just an open circuit. The voltage measured is the input voltage. For this reason, you should mention the voltage measured with respect to no loading, half loading or full loading conditions, etc... Then, Accphoto may understand correctly.
In summary, there are two kinds of method to step down high DC voltage to low DC voltage:
1) Without using IC (not constant DC output):
=> The simplest method is use resistor. But, with different loading, the voltage drop in the resistor is different which causes variable DC output.
2) With using IC (constant DC output):
=> Using voltage regulator or IC (integrated circuit) and called DC to DC converter which exists both linear and switch mode. It can provide constant DC output. But, select low noise IC for audio device. There are thousand of topologies in DC-DC converter design. Just few references at
=> video lecture at http://www.youtube.com/watch?v=WMi-ZN3qtSs&feature=user
=> http://www.powerdesigners.com/InfoWeb/design_center/articles/DC-DC/converter.shtm
=> http://www.maxim-ic.com.cn/appnotes.cfm/appnote_number/2031/
=> http://en.wikipedia.org/wiki/DC_to_DC_converter
=> Photo as below. Today’s DC to DC converter is very compact, like a IC chip. Applications include notebook computer, mobile phone, ipod, etc... For Hi Fi audio device, I never try!
You may continue this topic with Accphoto as he is a practical guy in here. Lastly, may I ask you a question: Are your boss called “Brother Thomas Favier” after seeing your email address and your principal subject is Economics? He is school supervisor of my son. If yes, I know who you are.
B. regards,
alant |