Great thanks - I will (may) need for short bursts or extended periods of time, so the later is the best optionAttached is a example diagram of how I would do it. I have used Dual Mosfet drivers and low RDSOn FETS. This gives superior performance and efficiency.
However, if you only need to turn the LED's on and off occasionally then you can get by without the Mosfet drivers and can use Logic Level FETs driven directly from the Picaxe via a 330R resistor.
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