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A little breakout board for DIP ICs with output resistors

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Hello all.

This is my first instructable! If you have any suggestions or questions, feel free to send me a PM.

After receiving my cheap (horribly packaged, that's what you get for being a cheapskate) 74HC595 shift registers from China a short while back, I decided it was time to give them a try.

I made a shaky first build on my breadboard but forgetting the resistors (thinking the current was perhaps internally limited by a resistor, silly me), got the IC really hot.

After building a second prototype I realized how much of a hassle it was to prototype with ICs on a breadboard, having to break out all the outputs with either wires and then connecting them to resistors, the LEDs and then ground, or jumping them straight away with the resistors, and how much easier it would be to have a small board with an IC socket and resistors built into the outputs to save me all the work of inserting resistors.

The fact that I wasn't sure if the ICs were broken or not meant I had to keep placing and replacing the ICs in my breadboard, with bent pins and frustration as a result.

I decided to make a little IC breakout board on a piece of protoboard with a socket for the IC, connectors directly connected to the IC and connectors connected to the IC through a 1kΩ resistor.

This would not only allow me to connect LEDs to the IC, but also to connect directly to the IC. While building the board, I realised it had another feature: the headers that are connected to the resistors can be used to pull the logic level of the IC inputs up or down! While 1kΩ isn't exactly the perfect value - I would generally use 10kΩ or 15kΩ - as it will draw/source a relatively large amount of current, it is still usable for high-power ICs or ICs with a high input impedance (the type of IC where a pull down/up resistor is specifically necessary) like CMOS chips.

Let's get started!

 
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dozer7893 months ago

Nice tutorial for a first timer! Looks good!

One thing, where did you get that roll of resisters? I normally just get mine off of all my junk electronics, but a roll would be so much nicer!

Aars_Man_Tiny (author)  dozer7893 months ago

Thanks!

I bought them off ebay, I think it's a roll of 1000. The cheapest one currently goes for $5.79.

Like aphburner says, best places for bulk are ebay and similar auction-like sites. I usually go to taydaelectronics for small quantities. They post 15% discount coupons on facebook every month and all their stuff comes pricked in antistatic foam and in an antistatic bubblewrap envelope! Their resistors go in quantities of 10 for $0.01 a piece, with volume discount.

If you want more values I would recommend banggood or dealextreme as they stock resistor packs for cheap. I recently bought a huge pack of 50 or so values, 1000+ total resistors for about $8.

Thanks... Might order from them!

apburner3 months ago

where did you get your socket from. Those are turned pins.

Aars_Man_Tiny (author)  apburner3 months ago

I found those on ebay.

APuckNut3 months ago

Nice idea. One small suggestion for improvement I have would be to us a 28pin zif socket instead of the ic socket you used. This would make substituting the ic a lot easier.

Nice work though

Aars_Man_Tiny (author)  APuckNut3 months ago
Thank you for the kind comment.

Yeah a ZIF socket would be a much more convenient, but I found them too expensive and I only own a large one.
apburner3 months ago

This would work great with a TLC5940 also. Just make the breatout for a 28pin dip.

apburner3 months ago

best way I have found to buy alot of resisters of the same value is Ebay or Aliexpress. I just did a search of Ebay and found 1K 1/4W 100pcs was around $1.5 shipped.