New LED enables small form-factor MR-16 replacements
Living in the US, it’s easy to see the world of LED lighting through Edison-bulb-illuminated glasses, but these bulbs are not necessarily the dominant light source, especially in Europe.
I heard at Strategies in Light this week that Europe has 1 billion MR-16 lights, which are small 35-50W halogen lights, about 2 inches long (or high) and costing about $12 each:
An MR-16 is an example of a small form-factor light, which doesn’t lend itself to a multiple-LED approach. For example, below is an older LED-based MR-16 with a slew of individual LEDs. There is no secondary optic because focusing all of those LED point sources is basically impossible. Fitting the LED, its power management circuitry, and heat sink into the MR-16 requires a single LED solution.
Targeting the huge market that exists for small form factor lights, Cree introduced this week its MT-G LED array that combines Cree’s EasyWhite color-mixing technology, a low thermal resistance of 1.5C/W, and an efficacy of up to 92 lm/W (560 lm at 6W), at 85ºC temperature, 3000k. (It’s good to see that LED manufacturers are starting to quote their numbers at real-world operating condition.) It fits into a 9.1mm x 9.1mm footprint.
Here’s how the MT-G compares in size to other Cree LED arrays:
With the MP-G you can now design an MR-16 light with a single LED, packing the LED, a secondary optic, the power management circuit, and heat sink all into the small MR-16 form factor. Cree has published a reference design including power control circuits based on parts from National, TI, and Diodes, Inc. Here’s how the circuits stack up in size:
For more on the reference design and its constraints, visit mtg.cree.com. (You can download the reference design here: It requires filling in a simple registration form.)
UPDATE: …And hot on the heels of Crre’s LED announcement is LEDzWord Technology’s introduction of its MR16-6.5W lamp:
“Just 2 days after Cree made its first official media announcement of a new lighting class LED designed for high-output small form factor directional lighting, Ledzworld launches the first lamp that integrates the latest Cree multi-die MT-G LED with its own superior thermal design and driver- technology.”
Sphex commented:
In the UK MR16-s have largely been superseded by the GU10 230Vac lamp in the same size reflector format, in general lighting applications. The low voltage lamp still has its niche in e.g. shop counter displays and bathroom lighting, and where a narrow beam type is needed. GU10s are available for around $1.20. Several manufacturers are marketing multi-LED GU10 replacements at $15-$20, but I think the challenge of providing equivalent illuminance while meeting reliability, EMC, power factor and operating temperature criteria has still to be met.
Greg W commented:
One of the biggest problems I've encountered is power supply instability manifested as flickering and/or strobing of the LED lamp. Most manufacturers outfit their low voltage MR16 fixtures with "electronic transformers" (really just a switch mode power supply) designed to drive a (maximum) 75 Watt halogen (resistive) lamp. They worked great for 20-50 Watt halogen lamps but are often unstable with the non-linear, 2 - 6 Watt LED load. The fixture manufacturers I've spoken with are way behind the curve by not offering low voltage fixtures designed for use with 12 volt, MR16, LED bulb. A fixture with an 85 - 264 VAC input with a 12 volt output stable from 1 to 10 Watts is all we need.
LED Light commented:
While working for a European semiconductor manufacturer, the retrofitting of MR16’s were the first identified LED applications. This was in 2005. Based on the information contained in this article and by some of the subsequent comments, these lights do not seem to be completely understood. MR16’s were originally used in slide projectors and then became more mainstream as smaller halogen can lights. LED replacements have been commercially available in the US since 2006 and dimmable versions are widely available. Cree is merely updating/improving already available products.
Pator commented:
MR16's are not for general lighting but for accent lighting so it will all depend on how good their reflector system is at focusing the light.
Lambert vdH commented:
Prices of MR-16 are generally lower: 2-4 Euro and very often dimmable solutions are applied. This will hamper LED replacement.
Andy T commented:
Assuming you didn't misinterpret half angle for temperature, Margery, ditto on the 85 deg C lumen output spec.
Bravo!
