I have an old CCTV camera at the front of my house. At night, the camera doesn't pick up much detail, so I'm building an infrared illumator which I'm planning to house in an old halogen security/work light so it 'blends in' a little.
I don't know whether to go for:
1. 150+ LEDs, powered at 1.5V/30mA directly by DC (with protection resistors); or
2. 30-40 LEDs, pulsed to a higher current (1A) for 10ms (or so) using a 555 timer and transistor.
By all accounts, pulsing the LEDs to a higher current makes them much brighter, and uses less energy (as it doesn't operate continuously), at the expense of a few additional components and the chances of them burning out faster. More straight DC powered LEDs mean I can angle the LEDs in the housing to create a wider viewing angle, and they'll not be as 'visible' (i.e. glowing red at night).
Space isn't a factor (6"x4" / 150mm x 100mm), but current requirement and overall energy useage is. I have a 12V / 2A power supply which I'm planning to use, and for efficiency I'd like to use the minimum amount of energy, with the maximum amount of illumination.
Planning on using LEDs bought on ebay from China to complete the project. "may139189" picture labelled "Asia Engineer" - says 60mA operating current. Good idea/bad idea?
Is pulsing worth it, and how many LEDs can I get away with using either option based on my 2A supply?
TIA!
Mikky