We have a PCB having three AD584 (TO5-8 Package) and two DC-DC converters THD 10-2423.
- PCB has total 6 layers including top and bottom planes.
- Three pins of AD584 are connected to ground on two internal ground plans as well as top and bottom planes through spokes.
- Four pins each of DC-DC Converter are connected to ground planes and rest of four connected to power planes.
- Components are new and have clean pins and have shiny appearance.
- Components as well as PCB surface finish are pro lead compatible.
- AD584TH pin diameter is 0.45mm and Plated through hole internal diameter is 0.85mm.
- DC-DC Converter diameter is 0.5mm and Plated through hole internal diameter is 1.0mm.
We are trying to solder these components manually as well as passing through wave solder machine. After soldering, solder joints on these ground and power plane connected pins don’t fulfill acceptable criteria of IPC-A-610D class III 7.5.5.1 Sported Holes – solder- vertical fill (A). Rest of the 5 pins on these three AD584 meet target condition in this respect (i.e. there is 100% fill).
For manual soldering, we are using bottom heat plate for PCB preheating up to 120°C and soldering station temperature set to 450°C (iron 150W).
For wave soldering machine, preheating temperature up to 120°C, peak temperature 245°C to 250°C and dip time 5-6 seconds.
Possible reasons for this problem and recommendations for its solution are required.
Best Answer
You mention the plane connections on the top and bottom are through "spokes", by which I assume you mean thermal reliefs. It sounds like you neglected to also use thermal reliefs on your inner planes, and as a result, that's where all your heat is going.
The only holes in planes (outer or inner) that shouldn't have thermal reliefs for hand or wave soldering are vias, which have plated connections.
This is not normally an issue for SMT boards, where the entire board gets heated to soldering temperature simultaneously.