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Topic: PCA9685 - I2C fading 16 LED driver breakout board (Read 8860 times) previous topic - next topic

Grumpy_Mike

Jun 15, 2011, 04:45 pm Last Edit: Jun 15, 2011, 08:12 pm by Grumpy_Mike Reason: 1
I am having made some small breakout boards for the PCA9685 chip. This is a NXP chip is in a TSSOP28 package with 0.65mm spacing so it is a bit hard to prototype with which is why I am having to make some boards. These are single sided and are suitable for soldering pins on for directly plugging into a soldererless bread board. The have space for surface mount current limiting resistors or a link as well as address setting links by using solder blobs. And of course space for a surface mount decoupling capacitor.


I am looking to see if there is anyone who would like to have some of these boards. The price would be £2.50 each plus P&P at cost. Payment by PayPal. I need to have an idea of the demand so I can order the right number. If you are interested then reply to this thread or PM me. Also for any questions about this or the chip then reply here.

About the PCA9685
One chip will directly drive 16 LEDs @ 20mA with 4096 levels of brightness by using PWM. Each LED requires it's own current limiting resistor in a current sinking mode. It is easy to add FET drivers to drive more or bigger LEDs. There are six external address lines making the total limit of 64 of these chips on a bus at one time. That's 16 * 64 = 1024 individually controlled LEDs before you have to bother with bus switching. Being I2C it is easier to site these remotely from the arduino than the TLC5940 and you can get I2C drivers to extend the range of the bus. There is total flexibility about the on time and off time of the LEDs so you can arrange things to minimise current surges by not having all the LEDs come on at the same instance, although they will appear to so. Software control is easy and I have already written functions to show how this works.

wdl1908

I'v got a question about where to find the chip within the EU?


wdl1908

A pitty that as a private person I can't order via the site. They request fax orders and it needs to be minimum 50 EUR.

Grumpy_Mike

Where about in the world are you? I am a private person and I order stuff off their web site. The only minimum order required is to get free postage, I can order any amount I want.

You can also get them from RS:-
http://uk.rs-online.com/web/p/products/7275649/?searchTerm=PCA9685&relevancy-data=636F3D322664663D5926696E3D4931384E4D616E506172744E756D626572266D6D3D6D61746368616C6C7061727469616C26706D3D5E5C772B2426706F3D3226736E3D592673743D4D414E5F504152545F4E554D424552267573743D504341393638352677633D5926

Plus the other distributors.

wdl1908

I'm in Belgium. and the belgian site has guidelines for private customers stated above.

rs-online is out also when I registered they asked for my VAT code number. I asked them about private customers and they answered in the negative for orders from private customers.


wdl1908

Mouser only ships from the US with a 20EUR shipping charge. a little expensive.

I know I have been looking at all the big ones and they or need a VAT number or ship from the US. I once ordered something from Digikey from the .be site and it was shipped form the US I had to pay 45EUR taxes.


wdl1908

I'll check out future maybe that will work out.

Now on another note you can buy SSOP28 breakout boards for about $0.70

http://www.futurlec.com/SMD_Adapters.shtml

Grumpy_Mike

Yes never ordered stuff from them. I here that the prices are good but delivery can run into months. Have you used them?

wdl1908

Yeah I ordered from them have not received it yet is only 3 days since ordering A friend of mine has ordered and received his shipment in about 8 days. So i'm confident.

Chagrin

Futurlec took about a month for me (to the US). They ship from HK.

MrNiceGuy

#13
Apr 19, 2014, 08:18 pm Last Edit: Apr 19, 2014, 08:22 pm by MrNiceGuy Reason: 1
I've got mine from here: http://www.aliexpress.com/item/pca9685pw-pca9685-pca-Good-qualtity-HOT-SELL-FREE-SHIPPING-BUY-IT-DIRECT/1307247311.html

costs 28 Usd for 10 pcs (free shipping). Delivery to Austria took about 3-4 Weeks (thats normal from China).


Breakout-Board is available here:
http://www.aliexpress.com/item/20pcs-lot-TSSOP28-SSOP28-MSOP28-SOP28-TURN-DIP28-28pin-IC-adapter-Socket-Adapter-plate-PCB-Suitable/1701544152.html

20pcs of them costs 5,23USD (free Shipping included ;-) )

Came without problems.

Have fun :-)

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