If you need assistance, please send an email to forum at 4hv dot org. To ensure your email is not marked as spam, please include the phrase "4hv help" in the subject line. You can also find assistance via IRC, at irc.shadowworld.net, room #hvcomm.
Support 4hv.org!
Donate:
4hv.org is hosted on a dedicated server. Unfortunately, this server costs and we rely on the help of site members to keep 4hv.org running. Please consider donating. We will place your name on the thanks list and you'll be helping to keep 4hv.org alive and free for everyone. Members whose names appear in red bold have donated recently. Green bold denotes those who have recently donated to keep the server carbon neutral.
Special Thanks To:
Aaron Holmes
Aaron Wheeler
Adam Horden
Alan Scrimgeour
Andre
Andrew Haynes
Anonymous000
asabase
Austin Weil
barney
Barry
Bert Hickman
Bill Kukowski
Blitzorn
Brandon Paradelas
Bruce Bowling
BubeeMike
Byong Park
Cesiumsponge
Chris F.
Chris Hooper
Corey Worthington
Derek Woodroffe
Dalus
Dan Strother
Daniel Davis
Daniel Uhrenholt
datasheetarchive
Dave Billington
Dave Marshall
David F.
Dennis Rogers
drelectrix
Dr. John Gudenas
Dr. Spark
E.TexasTesla
eastvoltresearch
Eirik Taylor
Erik Dyakov
Erlend^SE
Finn Hammer
Firebug24k
GalliumMan
Gary Peterson
George Slade
GhostNull
Gordon Mcknight
Graham Armitage
Grant
GreySoul
Henry H
IamSmooth
In memory of Leo Powning
Jacob Cash
James Howells
James Pawson
Jeff Greenfield
Jeff Thomas
Jesse Frost
Jim Mitchell
jlr134
Joe Mastroianni
John Forcina
John Oberg
John Willcutt
Jon Newcomb
klugesmith
Leslie Wright
Lutz Hoffman
Mads Barnkob
Martin King
Mats Karlsson
Matt Gibson
Matthew Guidry
mbd
Michael D'Angelo
Mikkel
mileswaldron
mister_rf
Neil Foster
Nick de Smith
Nick Soroka
nicklenorp
Nik
Norman Stanley
Patrick Coleman
Paul Brodie
Paul Jordan
Paul Montgomery
Ped
Peter Krogen
Peter Terren
PhilGood
Richard Feldman
Robert Bush
Royce Bailey
Scott Fusare
Scott Newman
smiffy
Stella
Steven Busic
Steve Conner
Steve Jones
Steve Ward
Sulaiman
Thomas Coyle
Thomas A. Wallace
Thomas W
Timo
Torch
Ulf Jonsson
vasil
Vaxian
vladi mazzilli
wastehl
Weston
William Kim
William N.
William Stehl
Wesley Venis
The aforementioned have contributed financially to the continuing triumph of 4hv.org. They are deserving of my most heartfelt thanks.
Registered Member #176
Joined: Tue Feb 14 2006, 09:35PM
Location:
Posts: 44
Hi All,
I want to start working on my new projects but all the parts I want to use are now all SMD only so its a little hard to build a rats nest prototype without making a pcb.
Farnell sell these
Will these work for most of the new smds like DPacks and the small SOT223 SOT23 I-pak and d-pak? I am guessing the will work with SOIC ICS as well.
Whats the best way to solder them using a fine tip a decent light and gluing them in place while soldering them in place? I think there is a glue designed for doing this.
Any one got any tips?
This is the first time I will be working with SMDs.
Registered Member #191
Joined: Fri Feb 17 2006, 02:01AM
Location: Esbjerg Denmark
Posts: 720
its really not that hard, a very clean fine iron tip, and a steady hand will do. you can also practice on old electronix stuff first. like broken laptop mobo and junk like that.
Registered Member #56
Joined: Thu Feb 09 2006, 05:02AM
Location: Southern Califorina, USA
Posts: 2445
Well, as long as you don't want to use any parts smaller than sioc, you should be fine with just a fine tipped soldering iron (preferably temp controlled) and plenty of flux. I cannot stress the importance of flux enough, it makes soldering much easier.
I wouldn't worry about to glue too much, seems to work fine to just hold them in place with a tweser, but it might make life easier for you. I would recommend something that is more just a sticky goo than a glue, so you don't have to wait for it to dry.
As to prototyping, the correct device to use is called a 'surf board' and can be bought from places like digikey or sparkfun for about $1/board that will handle a single chip. This does get expensive tho... They have a set of pads for the chip, and then either pins on the side, or just pads to build the circuit on the board.
If you would be willing to draw up a layout for your converters for whatever pinouts of chips you need (sioc-8 and 16, to-23, and 8035 packages come to mind) I would be happy to etch a board of them for you. I could do a 2x5" of you design board shipped for $20.
I also have tons of smd parts if you need anything, just see my assorted components thread.
Overall I would recommend that you use a hybird approach to prototyping, using smd components of the 'big' components like the ic's, and using normal leaded resistors/caps/led/etc all on a bread board; because no matter how hard you try you are going to end up with a major rats nest of wires running around after the first few revisions which makes it very hard to use a soldering iron on the board (thus being able to plug the stuff in is a good idea).
Registered Member #176
Joined: Tue Feb 14 2006, 09:35PM
Location:
Posts: 44
... wrote ...
Well, as long as you don't want to use any parts smaller than sioc, you should be fine with just a fine tipped soldering iron (preferably temp controlled) and plenty of flux. I cannot stress the importance of flux enough, it makes soldering much easier.
I wouldn't worry about to glue too much, seems to work fine to just hold them in place with a tweser, but it might make life easier for you. I would recommend something that is more just a sticky goo than a glue, so you don't have to wait for it to dry.
As to prototyping, the correct device to use is called a 'surf board' and can be bought from places like digikey or sparkfun for about $1/board that will handle a single chip. This does get expensive tho... They have a set of pads for the chip, and then either pins on the side, or just pads to build the circuit on the board.
If you would be willing to draw up a layout for your converters for whatever pinouts of chips you need (sioc-8 and 16, to-23, and 8035 packages come to mind) I would be happy to etch a board of them for you. I could do a 2x5" of you design board shipped for $20.
I also have tons of smd parts if you need anything, just see my assorted components thread.
Overall I would recommend that you use a hybird approach to prototyping, using smd components of the 'big' components like the ic's, and using normal leaded resistors/caps/led/etc all on a bread board; because no matter how hard you try you are going to end up with a major rats nest of wires running around after the first few revisions which makes it very hard to use a soldering iron on the board (thus being able to plug the stuff in is a good idea).
Have fun!
Cheers for the advice. Basically I am going to use regular parts as best as I can but the inductor and mosfet / diode FETKEY package is all in SMD so I have about 4 SMD parts the rest can be regular components just rats nested to the PCB. My idea was a peace of that SMD board glued to a peace of copper clad and cut out aeras for common ground and supply and of course the power supply then use vero board (strib board) to use with the regular parts and micro. Might look a mess but it will get the prototype working as fast as possible.
Diode and Mosfet combined in one package. This sucker is really nice RDS on is 0.27 ohms, VDS is 20V, ID @ 25 deg is 1.8A and IDM is 22A. It’s in a SO-8 package.
These parts are crucial to the design so I am using them as they are in SMD form. Everything else is standard resistors, capacitors, 8 pin SOIC micro etc.
Registered Member #56
Joined: Thu Feb 09 2006, 05:02AM
Location: Southern Califorina, USA
Posts: 2445
The so-8 package isn't all that hard to use... I have seen people that have successfully made an adapter out of perfboard (pad per hole). You take a piece 5 holes wide and 4 holes long, then use an exacto knife to remove the middle 4 pads (going the short way), then the one on either side of middle at the ends (4 more) then cut the two remaining pads in the middle in half (make the cut parallel to the short axis). Then you can solder the chip on the two cut pads, then use a little wire to jump the top/bottom half of the split pads to the 8 pads remaining on the sides, and then solder a piece of 26awg solid wire in each of the 8 holes on the side. If you have no clue what I am talking about, I can draw a pic for you.
Registered Member #176
Joined: Tue Feb 14 2006, 09:35PM
Location:
Posts: 44
Hi,
Thanks I have seen that method. I will order the parts today and some fine wire and a peace of that board hopefully the stuff should be here tomorrow so I can build my prototype. I have some SDM adsheive on my parts list so that should help and a very fine soldering iron tip and fine solder any way.
Thanks for the tips I think I know how to go about this now. I also got a small pair of tweezers.
It will be a half and half prototype and I will post some pics. Some SMD some regular parts just to make it easier on me.
Registered Member #30
Joined: Fri Feb 03 2006, 10:52AM
Location: Glasgow, Scotland
Posts: 6706
I've managed to prototype a power electronic circuit using those SO-8 MOSFETs, switching about 2.5A at 5V. I just built it with the method I usually use, on double-sided copperclad PCB that I carved up with a Dremel. The prototype worked fine and translated well to the 4-layer PCB that I used for the production unit.
This site is powered by e107, which is released under the GNU GPL License. All work on this site, except where otherwise noted, is licensed under a Creative Commons Attribution-ShareAlike 2.5 License. By submitting any information to this site, you agree that anything submitted will be so licensed. Please read our Disclaimer and Policies page for information on your rights and responsibilities regarding this site.