Newbie on SMD. From THM to SMD PCB design and manufacturing [closed]

Question

I have made a prototype of a device using THM technology. Now one of my successful friends has suggested me to move the design to SMD technology to reduce component and PCB manufacturing costs. I have started struggling and tried to research what's best to do but still not happy.

1) A PCB Design Tool with a rich library as in ready to use (better than Proteus at least, I have tried Altium as well but still not happy) so I don't have to struggle every time to find the footprint, model, design, measures and so on (real pain sometimes or anyway quite annoying for many devices).

2) How do you choose which manufacturer and which package to use? (there are too many)

3) Do you really need reflow-oven for QFN (microcontrollers)?

4)Sometimes SMD components have so many different versions/codes just because of their different ordering packaging type and it just makes it hard to take a decision.

Any further suggestion would be good. Thanks anyone for their time.

Answer 1

Moving to SMD is a good idea.

1) I have yet to find software that has completely satisfied me with its built in part/footprint libraries. KiCad has recently become very usable, and has decent libraries. I would recommend taking a look at it.

2) I choose parts by going to a site like Digi-Key and using their parametric search. Once I have narrowed the list down to my required specs for a given part, I often sort by price and pick the cheapest part that seems to be available in large quantities. This is an attempt to not chose parts that may be hard to source later.

3) No. You can hand solder (with traditional iron, or hot air) almost all SMD parts aside from BGA. If you do want to go the reflow route, I have had success with anything from a toaster oven to a panini grill.

4) Unless you are manufacturing at high volume and have a pick and place machine, package type is nearly irrelevant. You can pick by price and availability.

I would also recommend getting a cheap inspection camera. These can be very valuable when soldering and/or inspecting your work on those tiny parts.

Answer 2

1. I suggest you get used to creating your own footprints and avoid the prebuilt libraries. If you use a program that supports 3D it's good to include accurate 3D models of the parts to ensure mechanical fit. Through-hole and SMT.
2. Manufacturer- is the same as any other part- based on meeting the specifications, expectation for current and future availability, and so on. Package- I usually consider second sourcing and distributor stock levels so I don't get stuck specifying some dog of a package that gets discontinued.
3. No you can do it with hot air (with a decent tool) or an IR work station. It's not easy to inspect afterward but you can see the part settle into position if you are doing it manually. Lots of liquid flux.
4. Yeah. The vast majority of components introduced have been SMT for the past decade or two, so relaxing the constraint to avoid SMT may feel overwhelming.