I'm designing a sensor triggered circuit that involves **220 V** passing on a PCB, so I designed the board thickness to withstand a maximum of **1.5 A**. The main load on the circuit would be a series of LED bulbs, each bulb draws **4 W** (says on package). I'm confused on calculating the maximum bulbs I can attach to the load, I'm guessing its one of those scenarios: 

> Max load = 1.5A / current per bulb = 1.5 / (4/220) = 82 bulbs
>
>Or does the manufacturer calculate power drawn from voltage regulator (5 V) and thus:
>> Max Load = 1.5A / Current per Bulb = 1.5 / (4/5) = 1.8 bulb = 1 bulb.


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