A lot of small quantity PCBs come individually routed these days, but when they get too small or come in larger quantities, panels can be very nice to have. When you have your PCBs panelized, what's your preferred method? And why?

We get questions about this reasonably often: "What's the best way to panelize my boards?" For our shop, we have some guidelines on how to go about it (make sure to follow the specific guidelines from whatever manufacturer is assembling your boards), but the guidelines don't specify whether you should use V-score or tab routed. That's a decision left to you.

V-score section What if you don't know? Well, it depends then, but you can easily eliminate a few options. For example, if you have curves in your board outline, you can't V-score. V-scoring only works in straight lines. With curves or odd shapes, you have to use tab-routed. If your outline is a pure rectangle, V-scoring tends to require less board-edgBoth tab and
v-scoree so you can get a bit more out of your PCB real estate. But it's more difficult to deal with on very thin boards and V-scoring leaves a rougher edge after snapping the boards apart.

Two of the key disadvantages of tab-routing are the greater waste area and the nubs that stick out after separating the boards. You can leave the nubs, sand them down or use a clean-up router.

Here's my take on it: A) If it truly doesn't matter, use whichever method is less expensive or that you think looks prettier. B) If you have curves or other odd shapes, you'll probably need to go with tab-routed. C) If your boards are rectangles and you can deal with the less-smooth board edge, go for the V-score.

Duane Benson

Tab. Not Diet Coke.