Yes... go narrower viewing angle for greater brightness, but in a=20 smaller visible area. I deal directly with SunLED regularly, who gives me better pricing than=20 available on Digikey etc. Also, depending on what system these are in, if you have a spare=20 microcontroller output, you may consider toggling them on/off rapidly as=20 you can halve the current and not lose half the effective brightness. Cheers, -Neil. On 5/27/2016 6:09 PM, Bob Blick wrote: > Hi Dwayne, > I don't have any part numbers for you, but I do have a couple of thoughts= about LEDs. mcd is a measurement of brightness at a particular angle, so t= he lens(and viewing angle) plays a big part in that number. Most SMT LEDs h= ave no real lens and the viewing angle is large, >100 degrees and the mcd r= ating is correspondingly low. Compare this to a through-hole LED with a cle= ar lens and a viewing angle of 30 degrees or less. So you might not look to= o hard at the mcd rating. > > The other thought relates to color. The short-wavelength greens are very = efficient but have longer lifespan than blues. They also have a high voltag= e drop, similar to blue LEDs, so if you are running at 3.3 volts you'll nee= d to pay close attention to your dropping resistor after choosing your exac= t LED. The greens I'm talking about emit at about 520nm. > > Happy hunting! > > Friendly regards, Bob > > ________________________________________ > From: piclist-bounces@mit.edu on behalf of Dway= ne Reid > Sent: Friday, May 27, 2016 12:09 PM > To: pic microcontroller discussion list > Subject: [EE] Looking for high-efficiency SMT LEDs > > Good day to all. > > I'm looking for a single-color SMT LED that gives me reasonable > brightness when operating at less than 1mA current. > > Neither size or color is critical - what I'm after is lowest cost > combined with highest brightness. > > Here's where I'm coming from. > > We currently use 5mm through-hole LEDs in most of our boards. The > green and blue LEDs are stunningly bright - even when run from only > 0.2mA or so. > > I've spent significant time looking for SMT versions of bright > LEDs. Unfortunately, most of the offerings from Digikey are way less > than 1000 mcd when running at 20mA. I need reasonable brightness > when running from 0.5mA or so. > > I'm in the design phase right now but I'm at the point where I have > to make decisions regarding the voltage dividers that these LEDs are > in series with. These decisions ripple through my entire design, up > to and including the power supply. > > Because these LEDs are near screw-terminal blocks, physical size > isn't an issue. But I want machine-installable LEDs - ideally with a > flat top (as opposed to a dome top). > > Initial annual quantity would be in excess of 10k but will be > increasing as I migrate more of my current through-hole designs to SMT. > > I'm okay with Asian suppliers so long as the product that I receive > is of consistently high quality. > > I'm hoping that someone can refer me to a supplier. > > Many thanks! > > dwayne > --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .