Article View: sci.electronics
Article #19856Re: speaking of LEDs
From: Ray Berry
Date: Tue, 04 Oct 1988 17:31
Date: Tue, 04 Oct 1988 17:31
18 lines
1325 bytes
1325 bytes
>>emergency light sources: Two LEDs, each in series with a 33-ohm >>resistor, connected to two alkaline AA-cells... > >Why not connect the two LEDs in series and use a smaller resistor. ... >Answer of sorts ... the forward drop across the LED >is too great. About 2 volts for green... I suspect a single-chip switching converter could be configured as an efficient method of powering a couple LEDs - for instance, two lamps in serial driven through a convertor designed to convert 5-9 vdc to a 20 mA. output current. A 9 volt alkaline could then power the lamps efficiently over a wide range of its service life. -- Ray Berry KB7HT Seattle Silicon Corp., 3075 112th Ave NE., Bellevue WA 98004 (206) 828 4422 UUCP:...!uw-beaver!tikal!ole!ray =============================================================
Technical Details
Message-ID:
<497@ole.UUCP>Path:
arc1-ca.pugleaf.net!utzoo!utgpu!water!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!mailrus!cornell!uw-beaver!tikal!ole!rayReferences:
<491@ole.UUCP> <7200014@silver> <779@mplvax.nosc.MIL> <1988Oct2.053515.18004@utzoo.uucp>Show Full Headers
Complete Article Headers
Path: arc1-ca.pugleaf.net!utzoo!utgpu!water!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!mailrus!cornell!uw-beaver!tikal!ole!ray From: ray@ole.UUCP (Ray Berry) Newsgroups: sci.electronics Subject: Re: speaking of LEDs Message-ID: <497@ole.UUCP> Date: 4 Oct 88 17:31:20 GMT References: <491@ole.UUCP> <7200014@silver> <779@mplvax.nosc.MIL> <1988Oct2.053515.18004@utzoo.uucp> Reply-To: ray@ole.UUCP (Ray Berry) Organization: Seattle Silicon Corporation, Bellevue, WA. Lines: 18