DIY DIP heatsinks? - Page 1
Forum section: electronics / beginners

author: dentaku
author_rank: Frequent Contributor
timestamp: November 05, 2015, 12:44:52 am
content: I have a clone Adafruit Motor Shield V.1 with two L293D drivers on it.http://arduino-info.wikispaces.com/file/view/DK-MotorShield-300.jpg/419382206/DK-MotorShield-300.jpgI was testing out various little bipolar stepper motors I salvaged from scanners, fax machines etc. and the L293D eventually gets very hot.Is there a good DIY way of heatsinking 16 pin DIPs like this? I don't have any adhesive thermal paste or pads.I've got a bunch of tiny heatsinks I can cut down to the right length easily.

author: fivefish
author_rank: Frequent Contributor
timestamp: November 05, 2015, 01:22:03 am
content: You can stick chipset heatsinks on top.http://www.ebay.com/itm/20x-Mini-Aluminium-MOS-IC-Chipset-Cooler-Cooling-Adhesive-Back-Heatsink-/321388575314?hash=item4ad4407a52:g:ZT4AAOSweW5VdrLg

author: krivx
author_rank: Frequent Contributor
timestamp: November 05, 2015, 10:11:35 am
content: You can use any thermally conductive material, just make sure to measure temperatures and don't assume you will get results that are as repeatable as with commercial heatsinks.Here are some homespun examples:http://tangentsoft.net/elec/diy-hs.html

author: dom0
author_rank: Super Contributor
timestamp: November 05, 2015, 11:43:01 am
content: Or you could use a modern current mode stepper motor controller that is much more efficient than the 1940s L293. Seriously, 3 V drop at 1 A load current is fucken hilarious today. Even fifteen years ago actually.

author: dentaku
author_rank: Frequent Contributor
timestamp: November 05, 2015, 02:08:52 pm
content: Quote from: dom0 on November 05, 2015, 11:43:01 amIt was cheap and I wanted to try it.I also have some A3967 based EasyDrivers that are tiny and don't get nearly as hot.

author: dentaku
author_rank: Frequent Contributor
timestamp: November 05, 2015, 02:15:34 pm
content: Quote from: fivefish on November 05, 2015, 01:22:03 amYup, That's what I was thinking about. Most motherboards has tiny heatsinks stuck to the bigger ICs.

author: fivefish
author_rank: Frequent Contributor
timestamp: November 05, 2015, 02:18:50 pm
content: I've used this one too.http://www.mouser.com/ProductDetail/Aavid-Thermalloy/501200B00000G/?qs=VJtzl2NKxc3RD4IPRgm%2FVg%3D%3D&gclid=CNPF4dy8-cgCFRc6gQodS7sPmw

author: dentaku
author_rank: Frequent Contributor
timestamp: November 05, 2015, 11:23:32 pm
content: Just for fun I decided to sand down a rather large heatsink with very fine sandpaper until it was perfectly flat, added some Artic Silver and attached it to the chip by stringing a piece of wire under the DIP socket and over the top of the heatsink.Here's a photo of it before I managed to tighten it correctly. It seems to work quite well. If you tighten it until the outer heatsink fins start bending a bit you can let go and the springiness of the fins keeps everything tight.

author: JoeB83
author_rank: Regular Contributor
timestamp: November 06, 2015, 12:03:47 am
content: It looks like that solution would work pretty well as long as there's thermal grease between the sink and the case and it's attached firmly. Another solution, one I've used in the past, was finding clip-on heatsinks designed for TO-220 and narrowing the clip so it fits between the IC pins.

author: dentaku
author_rank: Frequent Contributor
timestamp: November 06, 2015, 12:19:18 am
content: Quote from: JoeB83 on November 06, 2015, 12:03:47 amHmmmI might have one of those.