I got a question guys. After searching online for info on how to read schematics I learned a couple things. I don’t understand a couple thins tho. I see a logic gate symbol. I realize that this is an ic, I looked at the ic at radioshack and I saw it had a lot of legs or pins on it, but in the diagram itself it appears as a kinda triangle but with three points of connection on it. How do I know which pins I use? Or do I use all the pins? I am lost. Any help
logic gates are a representation. So you need to remeber each IC can have a differn't pin for a differn't part of the logic gate, so you need to look at the datasheet for your logic gate. There are a lot of standard types of logic gates. A quick google for the number on the one you saw at radio shak should get you a datasheet which shows you which pin does what.
helped yo thanks a lot mang, I found the data sheet, but it only brought me to the sad realization I may not be able to do this. Its like climbing up a hill with butter on my shoes, it gets more and more difficult. Argh! Someon help me
You should just have to connect the vcc and gnd pins on the chip to get it to work. You may have to set some options or whatever by connecting a few pins either high or low. The rest of the pins you should be able to leave hanging, and just use the three for the logic gate that you need.
" a triangle with 3 pins" sounds alot like an OP amp not a logic gate. A pic of the schematic would be good to make sure. Or a part number.
Thanks. Ok, I can identify the VCC and a ground pin on the chip thanks to data sheet(I still need to know the third pin or combinations I may need to solder). Now, the dilemma is, I don’t know which pins I solder to what. I drew a logic gate symbol with mspaint, don’t laugh, can anyone explain what the parts of the sybol represent. Thanks (yeah guys you gonna have to spoon feed me on this one). Component list C1 22 uF 10V electrolytic C2 22 uF 10V electrolytic R1 2.2 kohm R2 2.2 kohm R3 1.8 kohm R4 1.8 kohm R5 2.7 kohm R6..R8 47 ohm U1 74LS86 or 74HCT86 T1 BC 547 T2 BC 547 i dont know if i put in the pics correctly hope it works *fingers crossed* ok i dont know how to post pics if anyone wants to talk to me and share the wisdom directly i am drewsinbk on AIM
you need to upload your pics to a web server. There are a few free ones out there. use the search to find them.
http://www.semiconductors.philips.com/acrobat/datasheets/74HC_HCT86_CNV_2.pdf will give you the datasheet with a pin-out. It's a Quad 2-input EXCLUSIVE-OR gate, which means you get 4 seperate gates in the IC, all using the same power supply. The datasheet will show you which pins go with each gate. woot!!!111 4k post
i'll keep thanking everyone, cause so far you guys helped alot i am still lost tho. but that last data sheet sure helped me on the wiring of the ic. this is the schematic i have been talking about all the time now i understand how to wire the ic im wondering if i should still use that one, i found another on starfoxs site and it seems to use alot less components perhaps just what i needed this is it anyone can suggest which one they think should use ? im leaning towards the simpler one, but i dont understand how to wire this ic or the capacitor. im lost. AS USUAL oh guys. one more thing. can i wire a resistor wrong? or could it go either way? Im new to this, can u tell
Quick answer about resistors Just to answer your question about resistors, you can connect them either way, so don't worry.
And the 22uF capacitors will have a stripe down one side of the can next to the negative lead if they're aluminium electrolytic types. Just to confuse people, tantalum capacitors usually mark the positive lead instead as here.
