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BREADBOARDING

by Stuart Ball

Start ý Grounding ý Placing Copper Strips ý Power Wiring and Supply Bypassing ý Lead Wiring ý Test Points ý Surface-Mount Parts ý Other Tips ý Putting It All Together ý Other Techniques ý Sources and PDF

OTHER TIPS

Sometimes you have to wire a connector such as an IDC header, where there are two rows of pins but all the wires come off the same side. With a PLCC or PGA socket, you have a similar situationýinner and outer rows of pins, with the wires of the inner pins having to pass through the outer pins.

Figure 4 shows the best way to handle such situations. Wire the inner rows first and solder the connections. Then wire the outer rows, passing the wires between the pins of the inner rows. This way, you donýt damage the insulation on the outer wires while soldering the inner pins.

Figure 4ýHere are some wiring tips for devices with two rows of pins and for wiring discrete components.

Also shown in Figure 4 is a tip on wiring discrete component leads such as resistors and transistors. When wiring these parts, wrap the wire around the component lead close to the board. If you leave a lot of component lead protruding above the perfboard, the leads are more prone to bend and adjacent leads may short together.

Because the perfboard doesnýt have any pads or traces, you can drill holes without worrying about shorting anything. Power devices, such as TO-220 regulators, can be bolted directly to the board.

The copper tape is about the same thickness as 1-oz. copper on a PC board, and you can use it in much the same way. If you are using small surface-mount power packages (such as DPAK and D²PAK), you can solder their power tabs directly to the copper for heatsinking. The only thing to remember is that the tape is stuck to the board with adhesive, not bonded. Too much heat will soften the adhesive, and the tape will let go. Any mechanical stress will eventually lift the tape unless it is clinched to the board (as described earlier).

Because the copper tape can be placed wherever you want it, you can have two independent ground grids. For example, you can have separate digital and analog grounds connected where power comes into the board.

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