0402

Sure. I had that same revelation when I first used them about three years ago at my PPoE. They'd never used them and the manufacturing guy was surprised how easy they were to use on the line, too. No problems at all.

At my CPoW, we use 0402s as the default size. The only issues I have with them are our design rules and jumper wires. Our 0402 pads are semicircular and barely larger than the device body (you really can't see the pad with the part mounted) This pad was designed to avoid tombstoning but it makes them a bit more of a pain than a scaled version of an 0603 pad. The other issue is attaching an EC wire to them. They're a little small (the relatively smaller pad makes it worse) to attach a #30 wire to than an 0603. It's certainly possible but a little more difficult.

I do like to use a Mantis if I'm going to work on them for any time but I can use a magnifier easily enough. I still try to use 0603s for parts I expect to change. One of my coworkers curses me when he has to change the 0402s in the customer's office. ;-)

The bottom line is that with a good solder station I really don't have any trouble with them. I don't really want to go to 0201s (or

I sometimes use a bunch of 0402s in parallel for hard bypassing problems. If you keep the flux off your tweezers so they don't stick, you can even bodge 0402s where there aren't any pads.

Cheers

Phil Hobbs

Did some EMC work a while ago, couldn't find any 0.1's in 0603 or bigger, only 0402. Needed to bypass a trace to a distant pad. So, tack the 0402 on the pad with a nice blob, run a wire from the other trace to the 0402 and blob it again. Just fine. I think it's not so much a matter of placing them -- you need awfully fine tweezers to do that -- you pick up the chip by one pad (making sure not to grab both pads and submerge it in the blob) and maneuver it over to where you need it. Drag off the blob and hopefully it stays behind, at the right angle.

Tim

Hard to do three or four next to each other that way, though.

I often put a small binder clip on the handle end of my tweezers, and slide it along the length of them to adjust the closure. That really helps prevent losing tiny parts when you shift your grip on the tweezers, and it doesn't get in the way.

Cheers

Phil Hobbs

If you put reference designators on the silk, there's hardly any advantage to going below 0603. And 0402s do tend to tombstone.

The sideways caps, like 0306's, are good high-speed coupling and bypass caps, like a row of 0402s.

You can see a couple of them here, just before the SMA connectors on the right.

You can't line 0603s up next to the pins of a .5mm QFP. They save a lot of space if you use a lot of them. Tombstoning indicates a problem with your process. I probably use 20x the number of 0402s as I do of 0603s.

I put a blob of solder on one pad, solder one end of the resistor to that pad, then come back and solder the other pad. That way the parts don't stick to the tweezers. They still have to be kept clean but it's impossible to keep them absolutely clean if you're using flux.

There's a huge difference in fragility between different parts- some you can manhandle significantly, others lose their end caps if you look at them sideways.

Best regards, Spehro Pefhany

In the same example, I later accidentally bumped that jumper wire... oops, back to the soldering iron. :o)

Tim

You can do that with 0402's? Show us a picture.

We tend to use resistor packs for stuff like that, like series terminating ADC outputs and such. Like U7 here:

They save a

I never use larger than 0402 for passives (especially R, C, and FB) unless larger is needed for power, voltage, current, Q, or some other fundamental reason. Coils do often end up larger than 0402, but not always.

I've been using them heavily for 15 years. Smaller parts (0201 & 0402) are a bit better with respect to frequency performance and are a must in dense designs.

Even 0805s are good to many GHz. It's best to match a resistor width to the size of the trace that it's terminating, so sometimes you want a wider resistor.

Do it all the time. Don't have pictures and no place to show them if I did. A 0402 is 1x.5mm so there is a little spreading but not much. Two fit in series and one across very nicely on .65mm spacing. I DACs with both spacings and this makes for nice tight output filters. They're nice for series terminations, too.

Coworkers like R-packs. I'd rather be able to remove or change one and they're expensive. 0402s are $.0005, give or take a couple hundred percent. Placing them isn't free but it's still a win.

One guy's hand shakes too badly to place them well but no one else has trouble with 0402s. It just takes some practice.

A Lithium Polymer charge controller recommended thermistor BC2534CT for cell voltage compensation. I should have checked the dimensions.

Holding them down with a fingernail and tapping the edges with an iron was the only way I could attach them. Solder paste and heating the board definitely didn't work. One side's solder always wetted before the other side and it flipped up vertically.

I once ordered a 1005. Problem was I ordered the 1005 Metric instead of 1005 Imperial. Simple pcb, I made it work. Learned something that day. Mikek

For the simple pcb's I've made, the smallest amount of super glue on a pin placed on the pcb, before placing and holding the part in place makes soldering easy. Great for one of boards. Mikek

yep made the same mistake, a 0603 capacitor kit turned out to be metric (0201 imperial) doing that by hand is pushing it

-Lasse

I know.

Sure. For example, a 10 mil Rogers 4350B core and a 50 ohm line mean stepping up from an 0201 to an 0402.