The Si8824EDB is surprisingly small. It would be great to fit this on a 5x8mm board inside the cable, but I didn't expect <1mm compionent size. We do have a bit more space available if you had a preferred alternative.
Yes, electronic components can be incredibly small theses days, and can fit into the smallest spaces. But fitting surface mount components can be extremely difficult, unless you are experienced and have the appropriate tools.
There are, in general, the following categories of component sizes:
(1) Tradition through hole: ideal for home makers
(2) First-generation surface mount: OK for home makers
(3) Second-generation surface mount: difficult for home makers (special optical and soldering tools required)
(4) Third-generation surface mount: impossible for home makers (extreme manual dexterity and expensive specialist tools required)
(5) Ball grid array (BGA): totally impossible for home makers (not only is the process difficult but joints cannot be inspected, so the success of BGA relies on a highly precise manufacturing control). But, low-pin-count BGA packages, transistors and opamps for example, can be mounted balls-up so that wires can be attached to the solder balls.
But, in spite of the above comments, some home makers do carry out all the above manufacturing processes, but they are exceptionally skilled and have the necessary equipment- often salvaged, re-purposed, or home-made.
In view of what you have said, I will have a look at a better approach for your USB pre-power supply.
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