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Topic: AVR's on the cheap? (Read 1 time) previous topic - next topic

focalist

Jun 06, 2012, 06:27 am Last Edit: Jun 06, 2012, 06:28 am by focalist Reason: 1
I've decided that I want to pick up some "other" AVR's, particularly a 644 or 1284.  These seem to be fairly steady in price, and I like DIP.  Bobuino convinced me that when I want tons more IO and memory, I can still "roll my own" with these chips.  SMT just isn't going to happen.. I have enough problem with DIP spacing, anything tinier would be a lost cause.

I expected, when I began looking at devices, to find that the ATTINY series would be cheaper..and have found that at the moment they aren't.  In addition, the cheapest TINY is a SOP8, and I've never used a SOP chip.  Certainly makes prototyping a bit tougher.

http://www.ebay.com/itm/1PCS-ATMEL-SOP-8-ATTINY13A-SU-ATTINY13A-TINY13A-SU-/250855806085?pt=LH_DefaultDomain_0&hash=item3a682bd485
ATTINY13A  .... $1.89 in qty one, delivered to USA from China.

http://www.ebay.com/itm/1PCS-IC-ATMEL-DIP-28-ATMEGA8-16PU-ATMEGA8-16PI-ATMEGA8-16PC-/260964533478?pt=LH_DefaultDomain_0&hash=item3cc2b2c4e6
ATMEGA8-16  .... $1.45 in qty one, delivered from China also.

Overall, this looks like a no-brainer.  Assuming that the bootloader is skipped, the small memory of these is still plenty for many projects, like one I want to do which converts standard 1602, 2004, etc LCD's to UART/SPI, to save pins on the Arduino.  Another is for color mixing of RGB LED's.  There's just no reason to dedicate a whole Arduino to tasks like these.

168's and 328's are still in the $3 and $5 range respectively.. I guess it may be worth the two or three bucks just to stay with a familiar platform.. but then again, if we did things the "right" way, I wouldn't be here in the first place.. nor would you, if you are like most Arduino junkies!
When the testing is complete there will be... cake.

Coding Badly


From what I can tell, the ATtiny prices fluctuate quite a bit.  Like you, I've occasionally found them to be more expensive than ATmega processors.  But you can't beat the size!

If you really are interested in the ATtiny13, try avnet.  The last time I ordered shipping was $8.00 and I had to pay sales tax (Texas).
http://avnetexpress.avnet.com/store/em/EMController?action=products&N=0&langId=-1&storeId=500201&catalogId=500201&term=ATTINY13A-PU

Osgeld

#2
Jun 06, 2012, 06:51 am Last Edit: Jun 06, 2012, 06:56 am by Osgeld Reason: 1
SMD really isnt that bad in certain cases (like 805 parts fit perfect on dip pads) or if you have time to make proper boards, SOP8 though your not going to plop on some perfboard without some ninja solderin-fu ahead of you (I dont like doing it and I just plopped 40 PLCC LED's on a 2x3 inch cut chunk of radio shack baord WITH SMD resistors stood on end! all with a smile)

some other dip options though would be the ATMEGA8, about 2.25$ at digikey, attiny44 at about 1.25$ at digikey, or the tiny2313 at about 1.32$ at digikey (and has a urart)

none of which get anywhere close to storage or ram of a 328, 644, or 1284, all the tinys get about 512bytes of ram, and smaller packages, but damn they are handy when you dont want to float a battleship on your perfboard, and really dont need all that much luxury ... I honestly use the attiny's more than any other MCU (just to get dumb crap done). Though on the other hand, if I want to deal with TV Out Lib or something piggy on ram out comes the aircraft carrier model 644 or 1284's (sometimes the MEGA 2650, since I have one now)
http://arduino.cc/forum/index.php?action=unread;boards=2,3,4,5,67,6,7,8,9,10,11,66,12,13,15,14,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,86,87,89,1;ALL

cr0sh


SMD really isnt that bad in certain cases (like 805 parts fit perfect on dip pads) or if you have time to make proper boards, SOP8 though your not going to plop on some perfboard without some ninja solderin-fu ahead of you (I dont like doing it and I just plopped 40 PLCC LED's on a 2x3 inch cut chunk of radio shack baord WITH SMD resistors stood on end! all with a smile)


I won't pretend to talk for focalist, but I think the hesitance at SMT work has more to do with health issues than anything else (please correct me if I am wrong here, focalist).

:)
I will not respond to Arduino help PM's from random forum users; if you have such a question, start a new topic thread.

Osgeld

#4
Jun 06, 2012, 07:25 am Last Edit: Jun 06, 2012, 07:27 am by Osgeld Reason: 1
one would be amazed on how much a drop of cheap super glue can help, I used to do it all the time ( or even setting your wrists on the edge of the table)

but! I am not going to go all

OMFG WTH IS YOUR PROBLEM SMT IS SOOOOOO EASY<<<< MUCH BETTER THAN TH WAFFLE WAFFLE WAFFLE

everything I do at home is though hole, like I said SMT ok in certain situations, otherwise break out the CAD and the acid, your blinky LED will work fine (heh) and its taken at least 6 months doing it damn near 12 hours a day to not totally suck at it
http://arduino.cc/forum/index.php?action=unread;boards=2,3,4,5,67,6,7,8,9,10,11,66,12,13,15,14,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,86,87,89,1;ALL

westfw

Quote
http://www.ebay.com/itm/1PCS-ATMEL-SOP-8-ATTINY13A-SU-ATTINY13A-TINY13A-SU-/250855806085?pt=LH_DefaultDomain_0&hash=item3a682bd485
ATTINY13A  .... $1.89 in qty one, delivered to USA from China.

Some products are NOT cheaper when bought on eBay and shipped from China.
The ATmega8 is apparently heavily used in "something" and I've bought cheap chips from eBay.
The tiny13a, on the other hand, is cheaper (as low as $0.58) from Mouser: http://www.mouser.com/Search/Refine.aspx?Keyword=attiny13&Ns=Pricing%7c0&FS=True

westfw

PS: I wouldn't consider the tiny13 a good choice for current experiments.  It's an old chip.  Better to try the ATtiny25/45/85 at about the same price (< $1 from mouser) and better features.

Jack Christensen

Mouser's prices have been hard to beat. The ATmega328P-PU price has dropped significantly, currently $2.50 each, $2.08 for 10, $1.95 for 25.
MCP79411/12 RTC ... "One Million Ohms" ATtiny kit ... available at http://www.tindie.com/stores/JChristensen/

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