LDR, photodiode or?

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Did the same thing (up-teem LEDs for one resistor. Made a Christmas Star and Seattle Seahawks emblem w. LEDs.
looked at using smaller LEDs (using 1206) but hand soldering is ??
 
You are limiting yourself a bit by using one resistor for a group of 4 LEDs. That means only one LED in each group should be on at a time. That saves maybe 3 cents per group of 4 (and admittedly, a lot of soldering) at the cost of only having a quarter of your LEDs on at any time.
 
At the risk of opening a very large can of worms, you could have boards assembled by JLCPCB. My only relationship with JLC is that I'm a satisfied customer.

Let's assume your board is 100mm × 100mm or less. The cost for board assembly breaks down like this:

1. Cost for 10 boards, engineering services and stencil: $13.50

2. Cost of components (per board): ~$3
JLC only has the PIC18F46K22-I/PT in stock. It's the big brother of the 18F43K22, with much more memory. It's $1.95 for 10+ pieces. The resistors, caps and LEDs would be pennies each at most. Probably less that a buck a board.

3. Cost for "extended" parts: $3 total.
The PIC is an extended part, meaning there's a charge to set up a pick&place machine with it. With careful selection, all of the other components should be available on the "basic" list.

4. Cost per pin for soldering: $?
This is some insignificant amount that I never even notice on my builds.

5. Shipping – DHL: $17

So for roughly $65, you'll receive 10 boards with [only] the surface mount parts installed.

Read this carefully: soldermask option is green. SMT parts are soldered to one side of the board only, and through-hole parts are your responsibility. Only parts in-stock and in their SMT library will be installed, and parts not on the basic list incur a $3 setup charge, which should only be for the PIC if other parts are selected carefully. Parts not in stock or not in their library won't be installed.

You're paying essentially $8.50 to have a lot of 10 boards assembled and getting a break on component costs buying though them.

If you want to do this, I'd recommend using JLC's free EasyEDA software – it will make it easier to provide BOM and pick&place files in the proper format. It's easy to use with a simple learning curve.

I have used this service for several boards and have been extremely pleased with the results. But be absolutely clear on one thing: For a successful build, it's entirely up to you to select components from their library and in-stock, and to be aware that only surface mount parts are part of the service.

 
I made similar using one resistor per led and yes it was a nightmare to assemble.
As mentioned before, I plan to multiplex just the blue leds then have the white leds with different patterns programmed so changing patterns constantly. Saves having to include the IR detector. Eliminating the battery saves on weight with slight cost increase with the USB ac adapter.
Will consider your idea of having boards populated by JLC.
I have an inquiry with JLCPB about cutting out the star pattern instead of the pattern on a square pcboard. Would make the project POP!
 
They can route any board outline you can draw that can be cut with a 1mm router bit.

I think I forgot to mention – green is the only option for soldermask color on assembled boards.

Add up the costs to assemble the boards yourself. The service is virtually free and would eliminate your perpetual problem of poor solder joins and bridges.
 
I have yet to have poor solder joints etc.
Since I went with the Hako soldering iron and really thin led solder, assembly of boards has been pretty easy but contemplating the JLC PCB assembly.
 
One more warning about jlcpcb.com, you may design for a specific basic or extended component BUT, if the component is out of stock when your board reaches assembly, they simply skip that component and ship your boards without that component. Also, they will not just give you a different 100 ohm 0805 SMD, they just skip it.
So, don't order unless: they have a bunch of the pieces you need OR you haave the skills to add the bits when the boards arrive.
 
That may have changed. I've received a notice when parts are out of stock when I'm ordering. So at least there is some warning.

I don't understand why they don't substitute generic parts if the basic part is out of stock. Any 0603 10k resistor is probably as good as the basic part when it's out of stock.
 
Last month, we submitted a project and they had more than 1000 of our LED in stock and our boards showed up empty in that place. No note, no notification - but they do warn you in the instructions that shipping empty is there policy.
 
I am going to give JLC a shot at my project and hopefully not have an issue with out of stock.
First I need to download the software and add a voltage regulator to my design.
Using JLC maybe I can get 805 LEDs and resistors? instead of the 1206 I am using as that is about as small as I dare hand soldering.
 
You do not need a voltage regulator if you are using a 5v USB power supply. The –K22 parts are happy with 5 volts.

Yes, you could use 0805 resistors and LEDs or even 0603 parts. You could also use one resistor per LED so you have more flexibility in operation.

Please don't take this the wrong way. I have used J LC's assembly service for about 5 or 6 boards with excellent results. I know they do a good job if you do your homework properly. I take ZERO responsibility for how anything you do with them turns out. ZERO. NONE. If you end up with a pile of scrap, not my fault.
 
Here are the "basic" 0603 LEDs available, so pretty much the standard colors. There are many pages of "extended" 0603 LEDs available – using an extended part is find if you can't find what you want in the basic list, but it adds a $3 service charge. There may be a limit on how many different extended parts you may use. I think it was limited to 10, but I'm not sure that still applies.

 
I down loaded the software from JLC now to figure out how to use it. I found 18f43k22 and started a schematic just for experimenting to see how it works.
snap to grid would be nice. it probably has it but ?
need more time with it.
As for the voltage reg. never hurts to be sure. The USB adapters are accurate and proper voltage??
better safe than sorry.
 
What to you get when you plug 5 volts into 5 volt regulater????

EasyEDA has numerous help files, tutorials and a forum. You should start at the start.
 
or use any other PCB software that can generate a gerber file. Jlcpcb has a gerber viewer to make sure the back side is flipped (mirrored) properly.
 
or use any other PCB software that can generate a gerber file. Jlcpcb has a gerber viewer to make sure the back side is flipped (mirrored) properly.

True. But it will be a lot simpler to generate the BOM and pick&place files in a usable format using EasyEDA.
 
When designing for assembly, you will save yourself a lot of grief by selecting available parts as you go, rather than going back later and updating details for every component on the board. This is especially true for the micro if it's in a different package with a different pinout. <Voice of experience.

The easiest way to select parts that are in the assembly program is to go to JLC's webpage and find the SMT LIBRARY under the RESOURCES tab.

(Click on the screen shots to enlarge)



Let's look for the PIC18F44K22. Enter it in the box at the top of the library page, and you'll get this. Oops. Only a few available in any of the package options. Bad choice.



The 18FF46K22 is the same part with more memory. Maybe it's a better choice?



Ahh. Lots of those available, in a TQFP package. Any package is OK, since JLC is assembling it. Looks like a winner.

Clicking on the part number brings up the page for this part. Lots of information there, including a link to the data sheet, which is very handy (although sometimes you get the Chinese language version). What we are most interested in is the LCSC part number. Click on the box at the right end of the row to copy this number to the clipboard. Then go into EasyEDA, paste this number (CNTL-V) in the search library function, and place the part on your schematic.




How about looking for other components, say a 10k 0603 resistor. Enter it in the search box on the JLC page, and you'll end up with several pages of parts.



This list includes basic and extended parts, of things including "10k" in the name, like 510k resistors. Let's narrow it down by clicking the BASIC option at the top left.



Read very carefully to select what part you want to use and click the part number as above to go to the page for that part. READ the description carefully to be sure it's the value you want. Use extreme caution. The way the list resistors is "10Ohm" – that's not a 100 ohm resistor. It's a 10 ohm resistor jammed against the capital O of ohm.
 
Am studying the easyeda tutorials but it just occurred to me that they only populate one side of the board.
My project uses both sides for cosmetic reasons. one side lots of LEDs and Lots of resistors (contemplating adding more LEDs and a resistors per port. (Jons suggestion is a good idea IF I go with an 805 LED package or even 603 instead of the 1206. More programming options but placing the pic on the front is questionable?
more thinking about this.
 
GETTING THE HANG OF THE EasyEDA
need to figure out how to put a single row of 5 holes for the ICSP port (footprint same as a 5 pin header but don't need to order the header.
have all the port pins with resistor(603) and led(805).
need to configure the LDO regulator and pad for the USB smt socket (micro B)
don't really want the PIC on the front but only way to have it assembled on one side only.
 
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