I'm working on a power filter for an LED lamp; the lamp is this bad boy:
https://www.amazon.com/gp/product/B00LN3Q37C/
I like it because it can run on 10-30VDC, which makes my life easier since I'm not hooking it up to your run-of-the-mill 12VDC automotive system.
The power supply I have handy is ~16VAC (I measured about 15.5V AC no load, I figure I should round up to give myself some margin of error). The first order of business is to slap in a full-wave bridge rectifier, so I'm not losing half the juice. That's no problem, I have one rated 1KV/35A that shouldn't even need heatsinking
After that though, I want to filter out the rectified sine ripple, and for that I need caps. If I recall correctly, the formula for calculating RMS voltage is
[latex]V_{rms} = \frac{V_{pk}}{\sqrt{2}}[/latex] which means to peak voltage should be
[latex]V_{pk} = V_{rms} \times \sqrt{2}[/latex]that is,[latex]V_{pk} = 16V \times \sqrt{2} \approx 23V[/latex] correct? So I should be fine and dandy with 50V capacitors? This value also makes me happy because it's well below the 30V rated max input.
The next order of business is figuring out capacitance... I don't even know where to begin on this. On past projects I just grab a decent-sized one and hope for the best, but is there any way to determine what will give me the best filtering without overkill? Instinct tells me a 2200uF cap might do the trick here... and since it's usually easiest/cheapest to get them in packs of 5 or 10, would it hurt to just throw two in parallel and call it a day (I'm pretty sure 4400uF
is overkill)?
Thanks!