Intro

Some devices required multiboard (2+ boards), let's see how to cheap and secure connect two different PCB.

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🔺 Issue Description

Board-to-board connectors not always appropriate, you can use gold fingers, but the main issue is that it should be used only for electrical connection, while mechanical connection should be separate.

PCI Connector needs Gold Fingers and not stable against mechanical stress	Soldering board into board may fail by the time (solder crack or delamination of the copper pad)

🔧 Issue Fix

Depends on board purpose it could be different, but the main idea is to use right angle pin headers and vertical pin socket for electrical connection. For mechanical connection using right angle terminal with screw. Some cases can use solder nut to achieve easy mounting/dismounting.

Recommended components

Electrical Connection

You can use standard 2.54mm/2.00mm/1.27mm pin socket and pin header. For small applications I can recommend 1.27mm pitch parts from XKB (with gold) for portable devices:

Manufacturer Part Number	Photo	Specs
X1321WR-2x13J-C40D18		-40℃~+105℃ 1.27mm 1.27mm 1A 1mm 2 250V 26P 2x13P Black Brass Gold Pin Header 弯插,P=1.27mm Pin Headers ROHS
X1321FV-2x13-C43D24		-40℃~+105℃ 1.27mm 1.27mm 1A 2 250V 26P 2x13P 4.3mm Brass Gold Square Hole Through Hole Top 插件,P=1.27mm Female Headers ROHS

Mechanical Connection

Manufacturer Part Number	Photo	Specs
TTR34083132-1140		1 13.2mm 4 40A M3 Plug-in type Side Tin 插件 PCB Welding Terminal ROHS
T34069		1 4 40A 5mm 9mm M3 Plug-in type (with screw) Tin 插件 PCB Welding Terminal ROHS
SMTSO30100CTJ		M3X10 Tin plated — Patch round nut ROHS

Hole

It's metallized oval hole, so it allows small deviations in terminal positions:

✔ Fixed

I have double-side vertical board, so placed terminals on both sides:

Conclusions