Post by thread:[EE] How did they fit Switching Mode Power Supply

Hi: I didn't expect a SMPS inside a flashlight lamp, but that's what the data shows. How did they do it? http://www.prc68.com/I/LED.shtml#E10LED -- Have Fun, Brooke Clarke http://www.prc68.com/P/Prod.html Products I make and sell http://www.prc68.com/Alpha.shtml All my web pages listed based on html name http://www.PRC68.com http://www.precisionclock.com http://www.prc68.com/I/WebCam2.shtml 24/7 Sky-Weather-Astronomy Web Cam

Brooke Clarke wrote: > I didn't expect a SMPS inside a flashlight lamp, but that's what the > data shows. How did they do it? > http://www.prc68.com/I/LED.shtml#E10LED Your web page quotes something I must have written several years ago, and links to a file that I put on the internet only temporarily (it even has "temp" in its pathname) and has long since been deleted. I have a much more recent and complete writeup of a LED headlamp at http://www.embedinc.com/pic/knli. ******************************************************************** Embed Inc, Littleton Massachusetts, http://www.embedinc.com/products (978) 742-9014. Gold level PIC consultants since 2000.

Brooke Clarke wrote: > Hi: > > I didn't expect a SMPS inside a flashlight lamp, but that's what the data > shows. How did they do it? > http://www.prc68.com/I/LED.shtml#E10LED > > You can tell if there is a switching supply by measuring the current with an oscilloscope. It may have visible current spikes. How much does it cost? Where did you get it? - Martin

Hi Enki: I think something like this is the answer. The specs say 2.8 to 12 volt operation (notice not 1.5 V) and 1 Watt power, so it's not really a joule theif. Hi Martin: No Scope needed. Just look at the bench supply meters as the voltage is changed. Data at: http://www.prc68.com/I/LED.shtml#E10LED shows constant 1 watt power load. $8 Superbrightleds.com T10-WHP Hi Olin: Thanks for the new link, I've updated my page. Hi David VanHorn: Yes. I think of Switching Mode Power Supplies as transformers for DC. -- Have Fun, Brooke Clarke http://www.prc68.com/P/Prod.html Products I make and sell http://www.prc68.com/Alpha.shtml All my web pages listed based on html name http://www.PRC68.com http://www.precisionclock.com http://www.prc68.com/I/WebCam2.shtml 24/7 Sky-Weather-Astronomy Web Cam

Brooke Clarke wrote: > Hi Olin: > Thanks for the new link, I've updated my page. I can see it changed, but the links to my site are still messed up, at least assuming you meant your page at http://www.prc68.com/I/LED.shtml. The link for "Olin Lathrop's early prototype circuit" is dead. That was something I put up temporarily for the purpose of the post you quote. Later you replaced what I wrote with "KnurdLight PIC Example Project" and pointed it to a live link, but that is not what the text is referring to. Please don't change someone's words without making it clear you changed them. Your misquote now makes some of my remaining text wrong, since the new link doesn't refer to any schematic with a 16F628 in it. Again, that text referred to stuff I put on the web temporarily just until people had a chance to read the post. Those the things referred to by that text are gone. The KnurdLight link (http://www.embedinc.com/pic/knli) is a current (and not temporary) page that talks about the same general topic, but is not the schematic the other text refers to. You are probably best off writing your own short description and referring to the http://www.embedinc.com/pic/knli link where a detailed writeup, schematic, and other documetation of one of my LED headlamps can be found. ******************************************************************** Embed Inc, Littleton Massachusetts, http://www.embedinc.com/products (978) 742-9014. Gold level PIC consultants since 2000.

Brooke Clarke wrote: > Hi Enki: > I think something like this is the answer. The specs say 2.8 to 12 volt > operation (notice not 1.5 V) and 1 Watt power, so it's not really a joule theif. > > Hi Martin: > No Scope needed. Just look at the bench supply meters as the voltage is > changed. Data at: http://www.prc68.com/I/LED.shtml#E10LED > shows constant 1 watt power load. $8 Superbrightleds.com T10-WHP > > Hi Olin: > Thanks for the new link, I've updated my page. > > Hi David VanHorn: > Yes. I think of Switching Mode Power Supplies as transformers for DC. > > Brooke, You posted numbers showing relatively constant power anyway, then asked "what's going on?" The oscilloscope was merely a suggestion. - Martin