Low output drive currents

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buck91's picture
Last seen: 6 min 58 sec ago
Joined: 07/29/2016 - 08:21
Posts: 582
Location: Michigan
Low output drive currents

Has anybody seen output tests of, well, any of the popular LEDs at lower drive levels? Specifically, what is mA difference between 1-5-15 lumens out of a typical 3535 LED such as the 219B these days? While I’m sure that number will vary based on efficiency between the various options out there, I would think at such a low level it would remain fairly tight.

Last seen: 12 min 59 sec ago
Joined: 02/25/2016 - 17:38
Posts: 580
Location: Uruguay

Cree PCT says 155 lm/W, 41.5lm, 2.67V for a XP-G3 R3 at the lowest measurement of 100mA. lm/W Efficiency seems to improve about 5% every time the current is halved, and lm/A 3%.

Extrapolating that I would guess about 33mA for 15lm, 10mA for 5lm, 2mA for 1lm. A bit more for the 219B because of higher CRI. At 1lm the driver could easily take more power than the LED.

Scallywag's picture
Last seen: 14 min 32 sec ago
Joined: 01/11/2018 - 22:23
Posts: 1735
Location: Ohio, United States

Yup we have big efficiency problems at low LED output with most of the blf drivers. It’s where zebralights really shine

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