Boards??

[liv&let dive]

Hey all, please could someone offer me some advice. i do not have the facilties to make my own board and need to use 11 LED's as outputs - which pic chip would i need and are there any boards available to buy which would support this??

 

[jwhooper]

I would also like to ask how most of you go about producing just one or two simple little boards. The web sites I visited make it look awfully complicated and rather expensive.

 

[Rickharris]

Personally, for small one off jobs I use strip board - The perforated board with copper tracks on the back to solder on to.<A href='http://www.rapidonline.com/productinfo.aspx?tier1=Tools%2c+Fasteners+%26+Production+Equipment&amp;tier2=PCB+Equipment&amp;tier3=Prototyping+Boards&amp;tier4=Stripboard&amp;moduleno=29453' Target=_Blank>External Web Link</a> This stuff

 

[eclectic]

Diver. Have a look at the AXE022.

http://194.201.138.187/epages/Store.storefront/?ObjectPath=/Shops/Store.TechSupplies/Products/AXE022P

John.
Following on from Rick, have a look
at the free evaluation version of this:

http://194.201.138.187/epages/Store.storefront/?ObjectPath=/Shops/Store.TechSupplies/Products/ABA010

e.

 

[hippy]

I'd also recommend strip-board, also called vero-board in some places.

As to which PICAXE you need to drive 11 LED's, that depends upon how you want those LED's to work. If you only want one LED on at a time it might be possible with just an 08 or 08M ...

http://www.rev-ed.co.uk/picaxe/forum/Topic.asp?topic_id=5123

If you do not need all to be on together, and 18, 18A or 18X may do the job, but otherwise you may need a 28A, 28X or 40X, or have to add some extra hardware to drive the LED's.

 

[liv&let dive]

yes, the LED's will be coming on one at a time

 

[dannydig87]

If you want to make your own boards, the easiest and cheapest way is to do it with &quot;press and peel&quot; film. Look at

http://www.jaycar.com.au/productView.asp?ID=HG9980&amp;CATID=&amp;keywords=peel&amp;SPECIAL=&amp;form=KEYWORD&amp;ProdCodeOnly=&amp;Keyword1=&amp;Keyword2=&amp;pageNumber=&amp;priceMin=&amp;priceMax=&amp;SUBCATID=

I have got excellent results over the time I have been using it. All you need is an clothes iron and some etchent. You will also need access to a laser printer or photocopier. I use to do it the photosensitive way, but I will never go back. It is so easy to do.

You get 5 sheets of 215 x 280mm transfer film in each pack.
Full instructions supplied.
4 Easy steps
1. Print or Copy PCB artwork onto film.
2. Iron on to a clean PCB.
3. Peel off. Toner and film coating will remain.
4. Etch

You can now make boards in minutes (it usually takes me about 20 minutes to do).

 

[dannydig87]

When it comes to drawing up PCBs, I use Protel Autotrax, which is available as a free download from the Altium website. It runs in DOS, and is a very powerful system. You can also find suitable graphics drivers (eg. 1024x768 resolution) from the Airborn web site. Do a Google search for both. I have also got a component library made by Silicon Chip magazine. I don't think it is available anymore, but I can upload it to my website if you wish.

Also, note that with Autotrax, you have to generate a Postscript document of your PCB file, so you will need GSView and Ghostscript to view and print your PCBs. It also does not come with a help file, so you will have to learn it yourself. It is a very logical program as you may find, so it is easy to learn.

///

When it comes to driving the LEDs, I would use a 4017 IC. You clock the input pin to switch to the next LED. Do a search for &quot;4017 led chaser&quot; and you will get circuit of 10 LED chasers. In order to have 11 LEDs, you will have to use two 4017 decade counters, and clock them both in the right order. That is, you clock one six times, then clock the other 5 times. In order to not make the other one repeat, study how the reset pin works. Sometimes discrete components are the best option.

Edited by - dannydig87 on 12/10/2006 05:07:33

 

[moxhamj]

For one-offs I use an experimenters board like vero board except that it just has circles round each hole rather than strips. I solder wire wrap wire to make connections, but you do need a proper wire wrap wire stripper to bare about 2mm of wire. Picaxes are so simple that with judicious placing of components only a few wire links are needed. For 2-5 boards it is worth etching a PCB. For more than that, email off the artwork and get it done commercially.

 

[premelec]

There are a variety of chips made to drive LEDs with serial input from a PICAXE - TI TLC5922 16 LED chan 80 ma - NSC LP3943 16 LED chan PWM... the downsides are tiny chips and long data strings to control the LEDs - the chips are not expensive - ca $4US

 

[inglewoodpete]

After the breadboard stage, if I have the need, I do 1 or 2 stripboard versions. If I'm planning more I use the Press-n-Peel method of producing PCBs.

P-n-P is a great way to do low cost, low volume or prototype PCBs if you have a LASER printer. Getting the iron temperature and time correct takes a bit of trial and error.

At A$6 per A4 sheet, P-n-P is not exactly cheap. I tried cutting the A4 sheets into 2 (A5) but got lots of jams in the printer. So, fill up the sheet with a few copies of the PCB you want, or do several different PCBs at once.

On the 11 LEDs, try an 18/18A/18X and use 7 output pins to make a 3 x 4 matrix. The 3 columns would each have a NPN ss transistor with current limiting resistor. Also put a current limiting resistor between the PICAXE and each transistor base. Total of 9 components plus the PICAXE and LEDs.