Dear CPF members,
today my OSRAM OSTAR arrived. It's a LE W E3B. Of course I share my first impressions with you.
In short: It is definitely bright. Very bright. I had to use solar shield foil (bought for the solar eclipse in 1999) to directly watch the emitter in action.
The first picture shows the OSRAM star on a CPU heatsink (normally used for a Pentium4):
The close-up picture shows more details:
On the next picture I fed the star with 18V 700mA (~12W).
I made some first measurements, or better observations (since they are not very scientific). All tests were made with the star laying on the heatsink with with a thin layer of standard heat-conducting paste between star and heatsink.
Minimum useful operating mode is about 15V @100mA. The LED gets quite bright already. Next major step in brightness is made @ 16V 300mA when it outperformes a Luxeon III. When operated at 20V 700mA it beats the pants off a Luxeon V at maximum power. I will provide comparison pictures soon.
One word about temperature: While running at low current values (100-500mA) it didn't get hot on the heatsink (30-32°C). When driven at 700-1000mA it got slowly hotter up to 37-40°C.
Next step for me is to find a suitable housing. I'm looking forward to receive a step-up driver capable of doing 22V 980mA from a low voltage battery source up to 4A input current.
Best regards.
today my OSRAM OSTAR arrived. It's a LE W E3B. Of course I share my first impressions with you.
In short: It is definitely bright. Very bright. I had to use solar shield foil (bought for the solar eclipse in 1999) to directly watch the emitter in action.
The first picture shows the OSRAM star on a CPU heatsink (normally used for a Pentium4):
The close-up picture shows more details:
On the next picture I fed the star with 18V 700mA (~12W).
I made some first measurements, or better observations (since they are not very scientific). All tests were made with the star laying on the heatsink with with a thin layer of standard heat-conducting paste between star and heatsink.
Minimum useful operating mode is about 15V @100mA. The LED gets quite bright already. Next major step in brightness is made @ 16V 300mA when it outperformes a Luxeon III. When operated at 20V 700mA it beats the pants off a Luxeon V at maximum power. I will provide comparison pictures soon.
One word about temperature: While running at low current values (100-500mA) it didn't get hot on the heatsink (30-32°C). When driven at 700-1000mA it got slowly hotter up to 37-40°C.
Next step for me is to find a suitable housing. I'm looking forward to receive a step-up driver capable of doing 22V 980mA from a low voltage battery source up to 4A input current.
Best regards.
I thought the 5W Luxeons were the most powerful emitters around.
