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Subject: Re: Website place
Name:
 Bob
Date: 6/28/2004 5:12:25 AM (GMT-7)
IP Address: 68.43.170.181
In Reply to: Website place posted by
LED
Message:
LEDs driven direct thru a resistor from a power source is fine down to 2.1 volts & maybe a bit lowwer using certain colors & certain types. My cheap modern white LEDs require 3.2 volts thru
3.7 volts the higher the voltage & higher the current the more light you get out of an LED.
Thou really LEDs are a current driven device.
The thing is I am driving my LEDs with short pulses so the voltage must be raised alot.
My guess is 9 to 14 volts & I will shoot for 9 volts & lowwer next. As a small cheap 9 volt battery normal brightness could last for over 10 hours, dimmed could last over 20 hours. Now an insane brightness could eat a 9v in 5 hours.
Because of heat direct power can not drive LEDS this bright only thru pulse width modulation can normal 5mm LEDs be driven this high.
Another thing is some japan white LEDs are already pure only about 1% made are of this quality & the price is over $1 per LED shipped. I have been buying Hong Kong LEDs & they will be coming out soon with the pure white type for 30 cents each. Still the japan good LEDs give off more light but they are not worth the price as no one will buy LED flashlights that are overpriced. I watched Ebay alot lately. They will not even buy a cheap 6 LED solar recharable flashlight for $15.
Bob
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