I understand what an inverter does , it takes say a Low signal and makes it High for example. Is there any way to test an 7406 out of circuit?
You're currently viewing posts by Pinsider BillinIndiana.
Click here to go back to viewing the entire thread.
I understand what an inverter does , it takes say a Low signal and makes it High for example. Is there any way to test an 7406 out of circuit?
EDIT:^^^ our post passed each other in cyberspace, Haha
Quoted from Spybryon:It should be either AND gate or OR gate right? So, look at the data sheet, find the +5v power and ground. Apply power and ground.
Next find a pair of inputs. Apply the right inputs and check the output. IF its OR gate the output should turn on with one input, if its AND gate the output should only turn on with both inputs.
I guess I should have said with a DMM. I have a power source but I don't have a way to apply Logic. Then again I guess that Logic is voltage right? huh?<< sorry still learning this confusing stuff.
So would applying say 2 vdc on the correct input pin(s) make the output pin High?
Quoted from terryb:There are people who test IC's with a DMM in diode/continuity mode. Sometimes you'll catch a problem, sometimes not. Best to test them in circuit or as I described above.
I tried to use my DMM in diode mode on Pin's 5 input and 6 output and I get an Open circuit with my leads both ways. So I thought I'd ask here.
Anyways I received my new 7406's in the mail today and I was just curious as if there was a way to test them out of circuit. I'm going to put a socket on my PCB anyways, but if you haven't noticed.... I ask a lot of questions...
Quoted from Spybryon:. Not sure where 2v is coming from unless Bill you just meant you happen to have that power supply laying around and wanted to use it.
I was just using 2 v as an example of what voltage would be needed to get a Low signal.. I'm a total noob to this, so I guessed a little high.. I know I would have hook a pot or something up to the 5 volt lead on my power supply to even get it down below 2 volts.. << There again I'm just guessing as if this would even work.
Quoted from KenH:or just get one of these:
Ebay link
That is pretty cool. I was just wanting to test kinda for the learning experience also. I doubt I'll ever work with 7400's enough to actually buy a tester.
Quoted from Noahs_Arcade:TTL chips are low below 0.7V and high above 3.5V or so. This will vary from chip to chip, so check your datasheet for those values. They should be Vil/Vih or something similar.
If you have a power supply, you have all the signals you need. 5VDC on the V+ connection, 0VDC (Gnd) on the GND connection. Then you use those existing 0V and 5V signals to test each inverting gate.
I just have an old computer supply I converted to a desk top power supply. It has -5 ,+5 VDC and -12, +12 and a Ground..
Quoted from vid1900:For $25 shipped, if you tested 2 chips it would be worth the time saved.
My tester was $499 back in the day, I can't believe how cheap that one is!!!!
Well it's like this, I'm still not sure I have the brain power for all this. I'm trying but I think I'll quote ole Forrest Gump with... "I'm notta smart man..."
Quoted from ChrisHibler:Yes, there is a way...
http://www.pinwiki.com/wiki/index.php?title=General#Testing_an_integrated_circuit
--
Chris Hibler - CARGPB #31
http://www.Team-EM.com
http://webpages.charter.net/chibler/Pinball/index.htm
http://www.PinWiki.com - The new place for pinball repair info
Thanks, I ran through the test and hey what do you know? A brand new chip is good.!
Anyways, I didn't know that whatever inverts the signal in the inverter would read as a voltage drop like a diode.
Also by placing my red lead on ground I'm actually going the opposite direction that the signal would be going, right?
That and in the test from Pinwiki it has me put my pos lead on ground and neg on each pin.. I show .5 or so with my DMM set to diode, so is there some kind of connection?
Quoted from terryb:Actually I never thought about it, but it is kind of drawn like all pins go to ground. The outer line is just the way they're showing the IC package, not a logical connection.
Quoted from Borygard:Every TTL device created is going to have *some* connection to ground, and 5V. That's how they work.
--
Rob Anthony
Pinball Classics
http://LockWhenLit.com
Quality Board Work - In Home Service
borygard at gmail dot com
I figured I was getting in a little over my head..LOL. I tend to overthink things sometimes.
You're currently viewing posts by Pinsider BillinIndiana.
Click here to go back to viewing the entire thread.
Wanna join the discussion? Please sign in to reply to this topic.
Great to see you're enjoying Pinside! Did you know Pinside is able to run without any 3rd-party banners or ads, thanks to the support from our visitors? Please consider a donation to Pinside and get anext to your username to show for it! Or better yet, subscribe to Pinside+!
This page was printed from https://pinside.com/pinball/forum/topic/7406-inverter-test?tu=BillinIndiana and we tried optimising it for printing. Some page elements may have been deliberately hidden.
Scan the QR code on the left to jump to the URL this document was printed from.