Is 48-HTSSOP ok ?

Archive BatchPCB
1

Hello,

I’m new here, so I say hello to all of you http://www.lsp-fr.com/forum/images/smilies/yo.gif

I’ve already ordered at BatchPCB and know of the overall quality of the work done, but this time I have a design with a 48-HTSSOP package. The design passes the DRC tests and is OK for processing. Nothing wrong here :wink:

My question was more about “quality” of the HTSSOP traces. Has anyone experienced it before at BatchPCB ? And if yes, what do you think of it ? I wouldn’t spend money (even if not expensive) for an unusable/unsolderable board :?

Thanks a lot

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I have not had any issues with Batchpcb making boards that are not solderable or were not good quality. The only issues so far have been my own or with manufacturer’s recommended footprints that are for reflow rather than hand soldering and don’t leave enough exposed pad next to the chip.

/mike

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Thank you, Mike.

I already have two PCB from BatchPCB and they are indeed very good quality. I was only wondering is such small traces as 48-HTSSOP were also this very good quality. Yuor answer does prove that it is the case, then :wink:

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I just received some 4-layer boards that have a 48-TSSOP, with 10mil and 7mil traces connecting to the pads. I am impressed with the quality of these boards. Very accurate copper areas considering the size of the features, and easy to solder by hand (if you are good at fine pitch soldering, that is).

The only issue was with the solder mask, but that was my mistake and it’s not a big deal anyway. The cell that you are using may be different, but mine has pads that are 12mil wide, and a solder mask feature that is the same size as the pad, meaning that there is a sliver of solder mask between each pad. This part of the solder mask is brittle, and ended up cracking off in some places while I was soldering the part. It would have been better practice for me to make sure there were no super-thin lines of solder mask in the design. Next time I will select the entire pad area on the solder mask layer, instead of just the pads themselves (I attached some pictures for comparison). I will also make sure my vias are masked off next time. :oops: D’oh!

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Thank you for this information ! FYI, the IC I’ll be using is a Texas Instrument DRV8821.

I’ve also noticed your issue with soldermask… Here’s what I have on my board :

So I think it will be good. Anyway, the PCB (2 layers) has been ordered yesterday. So, even if there’s a problem, it’s now too late :oops: At least with this batch.

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Just to follow up : I have received and soldered my PCB : works like a charm :wink:

But since it was my first try to SMD soldering, it’s not as clean as it should be, though :?

http://www.lsp-fr.com/astro/wp/wp-conte … soudee.jpg

I have made 2 mistakes on this PCB but it doesn’t prevent it from working.

For those who want to know what it’s about, it’s a multi-motors controller board for the FEZ Panda board. It can control 2 DC motors via PWM, 2 bi-polar steppers with 1/1, 1/2,1/4 and 1/8 step and 4 servos. It also contains a 256K EEprom and exposes 4 I²C headers, along with two +5V headers.

A video showing it in action with 3 motors : http://www.youtube.com/watch?v=uJdoQxI-R4o

This shield is mainly thought for the Panda board but can also be used on a Domino board, but then the servos and steppers won’t work.

So, I’m happy with this fabrication.

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nice job! Looks like a pretty fun project. Good to know that a TSSOP works with 2 layers as well. My first time soldering SMT didn’t look nearly as good as that, lol.