• Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

QFN28 to perf board adapter?

Status
Not open for further replies.

dknguyen

Well-Known Member
Most Helpful Member
Last edited:

DirtyLude

Well-Known Member
You can get breakout boards for these at online retail outlets. Sparkfun.com sells them.
 

MrUmunhum

New Member
Thinking about that.

Lude,

That is an option I have been thinking about. I really don't like PCB because of the damage to the environment. That's way I like using perf boards. Maybe I am too simple minded but I think that perf boards have less of an impact than PCBs.

I got off on this tangent while working on a simple man-machine interface for a project I am developing where a user can use the tty (serial) ports to control the actions of a running program. I babble now!

Back to the point, I have found USB to Serial interfaces on the net for less than $10 US, I was just looking for a way to incorperate the USB-Serial chip into the project for less than that. If it was a DIP and not an QFN footprint then it would be workable. I guess that I will abandon the idea?

Thanks for all of your comments and you time.
 

DirtyLude

Well-Known Member
I remember some very old posts on this board talking about environmental impact and waste concerning etching chemicals. As far as the boards go environmental impact should be the same. As far as etching goes, there are etchants that are 'green' alternatives to ferric chloride, if that's what you are worried about.
 

MrUmunhum

New Member
I remember some very old posts on this board talking about environmental impact and waste concerning etching chemicals. As far as the boards go environmental impact should be the same. As far as etching goes, there are etchants that are 'green' alternatives to ferric chloride, if that's what you are worried about.
Yes, I don't trust any manufacturer to safely process etching PCB!

I worked for Amdahl here for 18 years. During that time, in one year there where 4 pregnancies in the manufacturing building, all four resulted in miscarriages. I don't trust how chemicals are used, especially off shore. Remember "Monolithic Memory", number one on the Super Fund List.

Off my soap box now.

I live Off-the-Grid and use as little resources as possible. I'm just trying to lessen my impact on Mother Earth.
 

Sceadwian

Banned
Those few bad polluters out there make the rest of the people that put good faith effort into keeping environmental impact low look bad. It sucks, but all that means is you should really do your homework about where you buy your stuff from. I would trust a PCB house over in house etching most days, they're likely going to have less of an impact than doing it at home will by large and far.
 

DirtyLude

Well-Known Member
I would trust a PCB house over in house etching most days, they're likely going to have less of an impact than doing it at home will by large and far.
Is this just an opinion based on no facts, or do you have anything to support this? What in house etching process are you comparing this too? I'm no chemist, so I have no idea.

From what I can see, Muratic Acid/Hydrogen Peroxide are pretty toxic as is, but seems to be able to be reduced to harmless components fairly easily. Hydrogen peroxide reduces itself to oxygen and water, and Muratic acid, you can add lime to neutralize it, or take it to your recycling centre.
 

Sceadwian

Banned
Muriatic Acid is stomach acid, it's not toxic at all. You can buy it at most hardware stores.
Hydrogen Peroxide isn't toxic either you can buy it at drug stores =) Concentrated they're dangerous though. And neutralizing it isn't the problem, it's keeping the ionic copper out of the ground water. Dissolved copper is toxic to most critters. A recycling center would likley throw you out on your ass if you brought a used etch bath =) The best solution for disposal would be to take it to a local Metal Finishing plant companies that do electro plating. They have waste treatment systems that are designed to take care of this stuff. I worked at one for 10 years. If you're lucky you can find a friendly waste treatment operator that'll take care of it for you, even small shops process so much waste that a few gallons of etchent would be no problem.
 

DirtyLude

Well-Known Member
Muriatic Acid is stomach acid, it's not toxic at all. You can buy it at most hardware stores.
Hydrogen Peroxide isn't toxic either you can buy it at drug stores =)
Because you can buy them at a store doesn't make them non-toxic. They are classified as toxic substances. I'm not going to drink them, that's for sure.

Concentrated they're dangerous though. And neutralizing it isn't the problem, it's keeping the ionic copper out of the ground water. Dissolved copper is toxic to most critters. A recycling center would likley throw you out on your ass if you brought a used etch bath =) The best solution for disposal would be to take it to a local Metal Finishing plant companies that do electro plating. They have waste treatment systems that are designed to take care of this stuff. I worked at one for 10 years. If you're lucky you can find a friendly waste treatment operator that'll take care of it for you, even small shops process so much waste that a few gallons of etchent would be no problem.
There's a place close buy that does this. They were trying to get me to plate my motorcycle frame. I guess a shiny frame somehow makes it faster. Something like stickers. I'm going to head over there sometime soon and see what they will do.

We have a toxic disposal site nearby that will take this stuff, but I have no idea what they do with it. Possibly high temp incinerator?

Thanks for the suggestion.
 

Sceadwian

Banned
I looked it up, the US considers HcL as toxic, the EU only classify it as corrosive. I don't consider it toxic, just extremely corrosive. The main reason I don't consider it toxic is because stomach acid is .5% Hydrochloric by volume. HCL is relativly easy to take care of if spilled it will evaporate, if it manages to get into ground water the only step needed is to neutralize it.

The US CDC site mentions briefly that ingested Hydrogen Peroxide could be toxic, but this is a wording oddity. Hydrogen Peroxide isn't regulated as a toxic substance by the EPA just as an oxidizer.

For the bad parts like the copper metal what is done is the PH is controlled usually via caustic soda and sulfuric acid to a certain range which is different for each metal. At that special PH range the metal tends to precipitate out of the sollution so they add a coagulant (polymer snott really fun stuff to play with) and sometimes aluminium or even ferric chloride to add weight to the precipitate, which goes through several clarifier tanks of various sizes and contructions until you end up with a sludge and treated liquid. The water is tested for purity and discharged to the sewer, the sludge is de-watered in a filter press, then heat dried to remove as much water as possible. That powder is then sent off to a plant that mixes it with concrete to immobilize it into large blocks and tosses it in the ground somewhere. Incineration is the LAST thing you would do to heavy metal bearing waste.
 
Last edited:
Status
Not open for further replies.

Latest threads

EE World Online Articles

Loading

 
Top