The board is 2 x 2.5” and used through hole parts since I had them sitting around. If I do it over again, it will be surface mount and much smaller (and with lower capacity FETs). I’d probably also put the high-current gate driver on the second PWM channel/FET.
Actually, you have to get rid of 21 Watts of heat in that circumstance. The 20 watts generated by the pelt PLUS the 1 watt of heat that is "Moved" from the cold side to the hot side.
texaspyro, any chance of you becoming some competition to TaskLED drivers? I love the H6Flex, but 40 bucks for a driver has gotta be a healthy profit margin, no?
Any chance of you making a cheaper version of the H6Flex?
40 bucks for the H6 flex is a healthy profit, but depending on the volume of them that are sold, it's not totally crazy. One cannot run a business for long on an unhealthy profit...
You're probably not far off simplec6.. With the cost of parts that don't pass QC and require rework or rebuild, the cost of RMA parts that fail in the field and must be replaced for the customer and the cost of overhead in running a business, that is actually just about the right breakdown. Most electronic manufacturers run at right around 50% material cost..
Anything less than that, and one is running a hobby, not a business. When material cost is more than about 50% of your sell price, you'll be losing money just about every time. There are limited exceptions (like products with VERY expensive materials or VERY cheap materials).