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adafruit / Adafruit-Eagle-Library

Slowly building up a collection of parts we use here ... This file includes some library parts from microbuilder.eu Most of 'em are either Eagle parts that I've changed a little to make them easier to solder, some are 'handmade' and a few are from microbuilder.eu Its released into the Public Domain - that means you can do whatever you want. We'd like it if you kept the author email/url in the part description, just so we can be alerted if there are errors. Enjoy!
http://www.ladyada.net/library/pcb/eaglelibrary.html
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74*125 package #23

Open buelowp opened 8 years ago

buelowp commented 8 years ago

I'm trying to use the 74*125 components for a little circuit I'm working up, but it seems the eagle library has these as individual transistors, not as the full DIL-14 package. I'm not very good with Eagle yet, so I'm not exactly sure if this is on purpose, or it's just an oversight. The 74*245 seems to be correct with pinouts and form though, so I think this is just a bug. Can someone let me know if that's true, or if it's right, how to use this form? Thanks.

uChip commented 8 years ago

The 74125 is a single package containing four independently controlled tri-state buffers. To use each buffer select the 74125 from Add... menu or button (choosing your preferred package option). Then click on your schematic where you want to draw. Each time you click Eagle will drop a single buffer. If you watch the pin numbers you will see that each buffer has different pins. You will also see that each buffer will be named the same with an "A", "B", "C" or "D" suffix calling out the individual gate in that package. Don't forget to add the power pins by using the Invoke button or menu. Have fun!

buelowp commented 8 years ago

Thank you for the feedback, I'll do that.

I haven't checked (at work now), but will there be a valid 14 pin chip available for the .brd file? How do I get that if not? Why is the 125 different from the 245?

buelowp commented 8 years ago

Sorry, I should just add I just bought the 74AHCT125 from you guys, and want to add it to an existing circuit I have in Eagle. It would be nice if there was a defined package for it unless I'm missing something.

uChip commented 8 years ago

The three options underneath 74*125 are all 14 pin dip packages so if that is what you bought, you are good. Most 7400 series parts have the same pinout across families (LS, C, AHCT, ...)(but not always across different packages: DIP, SOIC, etc), but you should always check to make sure. In this case, I checked and they do have the same pinout. The package will be added to the board file when you add the first gate into the schematic. BTW, I don't work for Adafruit. I was just being helpful. ;-)

LGKev commented 7 years ago

I am so glad that I found this. "Invoke" is what I needed to correct my board! Thank you so much

afreeland commented 5 years ago

I am also very new to creating schematics and PCB..as in first time. Here is a fritzing of how the the 74AHCT125 is wired up would love some advice as to how this maps to the transistor symbol? The blue is connected to GPIO 18. image

This is all I have currently setup for the Pi Zero W image

Looking at the technical specs here it looks like I am only using 1 of the level shifters. Just not quite sure where/how things should map up... image