Trying out SMD, any parts advice?

fab
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I have had a couple of boards fabbed and honestly was amazed at the simplicity, speed, and cost of getting this done. I am just NOT going to hand wire any more. I have been doing through-hole parts which has been fine as I don’t normally need to use more than one of these boards at a time. This latest design (once completed) is something I am thinking I will need to be able to “just use” with minimal manual intervention so thought it would make sense to consider as part of getting this board fabbed, get the basic parts installed too.

I assume that means using SMD parts vs through-hole. I have never used surface mounted parts before and the different descriptions of the SMD sizes is a bit confusing. There does not seem to be an option of “I don’t care” for selecting a SMD part. In this specific case it is some MOSFETs, a few resisters, and a couple of diodes.

For the MOSFETs it looks like the main options are D2Pak or DPak. The part is a IRLB8721PBF (if that matters). Since it is only a 3-pin device, DPak preferred?

As for the resisters, the different available options all appear to affect size, is smaller cheaper? Or is that not a cost factor in such a common part? What would be the more common side to use?

The diodes are just a pair of rectifier diodes to protect the circuit in the case of accidental power lead reversal. There are three options, is there a “most popular” choice?

Thanks.

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Which website are you going to use for PCB fab?

If u are using Aisler (the Fritzing Fab), not that you will be getting a bare board… (I.e. hand-solder all SMD parts…

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I have had very good results with JLCPCB (the two prior times I have used them). They can take the gerber files from Fritzing though I have not [as noted] ever tried getting them to place the parts. This is not a very complicated board from a parts count perspective and I could very easily do what I have always done and hand solder them, I just thought I would try it this time to see how the overall process worked (having them do the parts installation) as well as the cost difference.

The boards I design include a micro-processor dev board and so the parts counts are typically low.

I looked at the one preferred by Fritzing and two or three others highlighted by youtubers a few years back and JLCPCB was the least expensive so started using them. Checked just yesterday between JLCPCB and PCBWay and wow, PCBWay was SO much more pricey, like 3+ times more!

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You need to manually create a pick and place file (Fritzing won’t auto generate it) there is a forum post on how someone did so if you search for pick and place in the forum search bar.

Peter