Author |
Message |
Team Toothpaste
Joined: May 06, 2010 Posts: 25 Location: London
|
Posted: Fri Dec 10, 2010 9:43 am Post subject:
4093 problems Subject description: I keep breaking cmos 4093's |
|
|
hi everyone, i'd just like to start by saying thank you to everyone involved in these cmos synths on this forum. about a year ago i started working my way through nic collins 'the art of hardware hacking' and over the last couple of months the Lunetta section n this site has proved an excellent supplement to it.
so thanks
I've built a few little modules with 4093's and 4040's and i seem to get through a lot of 4093's (of the 6 or so i've bought only one still works) is there something i should be doing to prevent this or have i just been unlucky?
thanks again - any replies apreciated! |
|
Back to top
|
|
|
tjookum
Joined: May 25, 2010 Posts: 360 Location: Netherlands
Audio files: 26
|
Posted: Fri Dec 10, 2010 3:41 pm Post subject:
|
|
|
welcome Team Toothpaste(excellent name btw.)
Good to see another person join the lunetta fun.
The most common issue with cmos ic's is a static discharge across the pins. The official advice is to use a grounding wristband to dissapate the charge. I always handle them with care avoiding touching the pins and never had any fails but if you have carpet it might be a different story. It's also a good idea to use IC sockets when soldering, exposing an IC to very high temperatures is never a good idea and it's easier to pop in a new one if the old one fails.
I would love to see/hear some of your modules. _________________ There he goes. One of God's own prototypes. A high-powered mutant of some kind never even considered for mass production. Too weird to live, and too rare to die.
Hunter S. Thompson
movies
noise |
|
Back to top
|
|
|
Top Top
Joined: Feb 02, 2010 Posts: 266 Location: California
|
Posted: Fri Dec 10, 2010 7:27 pm Post subject:
|
|
|
Make sure the ground pin is well connected to ground. I have noticed that 4093 (and probably other CMOS) get very hot if the ground connection comes undone but there is connection to ground elsewhere (such as through an oscillator with a cap to ground).
I've killed a few myself, usually making wrong connections/experiments. Seems a cap connected from +v to some of the pins might mean the end of at least that particular NAND gate (I've killed single gates on chips where the other three kept working). _________________ ∆ A.M.P. ESOTERIC ELECTRONICS ∆ |
|
Back to top
|
|
|
Team Toothpaste
Joined: May 06, 2010 Posts: 25 Location: London
|
Posted: Sat Dec 11, 2010 5:01 am Post subject:
|
|
|
Thanks guys,
@tjookum, i use sockets but i also have a carpet, don't use a wrist band and have never taken particular care not to touch the pins - sooo I'll try those things and see how it goes (can't really get rid of the carpet though)
- my first machine is already being butchered for newer, more versatile modules... i finished it in a hurry for a college project, and also learned a lot by actually making it... the new one will be better... but i'll upload some pics and sound when i have them.
@Top Top i think once or twice i have accidentally touched the battery to the wrong terminals. could that cause the kind of problem you're talking about. also i meant to say that most of mine are partially working (with one or two gates not functioning properly) maybe an on switch to prevent terminal mishaps in future would be a good idea.
thanks for your quick replies guys! |
|
Back to top
|
|
|
rich decibels
Joined: Apr 01, 2010 Posts: 60 Location: Wellington, NZ
Audio files: 1
|
Posted: Sat Dec 11, 2010 7:00 pm Post subject:
|
|
|
Hi TT - also I'd recommend grounding unused inputs. If inputs are permanently connected to some other gate then you don't need to ground them at all. If you have any inputs that are to be permanently unused then wire straight to ground. If you're using patch cables (etc) then you'll have inputs that are sometimes connected and sometimes not - in that case tie your input to ground via a 100k resistor. This works like a default value for the input that it will return to if there's nothing connected.
The other thing you want to do is add some polarity protection, to stop you from killing everything if you accidentally touch the battery the wrong way round. The easiest way to do this is with a single diode (1N4004 etc) across the power input, with the bar side to the positive battery connection.
|
|
Back to top
|
|
|
Team Toothpaste
Joined: May 06, 2010 Posts: 25 Location: London
|
Posted: Sun Dec 12, 2010 6:09 am Post subject:
|
|
|
thanks rich, i already do the pull-down resistor thing. but that's a really useful tip with the diode - when you're self taught you occasionally miss little gems like that - i'm sure i killed 2 of the gates on a 4093 just the other day by touching the battery to the wrong terminals, such a simple solution that i probably never would have thought of.
- this forum is awesome, i hope i can be of use to some of you some time! |
|
Back to top
|
|
|
stolenfat
Joined: Apr 17, 2008 Posts: 476 Location: Sunny Oakland California
Audio files: 1
|
Posted: Mon Dec 13, 2010 3:43 am Post subject:
|
|
|
so here an interesting one for ya:
the 4093 i currently am using isnt spitting out a square wave.
Instead its spitting out some noisier waveform, which sounds akin to white noise.
The other oscillator that gates the one sent to amp seems to pitch/filter the noise.
Theres nothing fancy going on, i cant seem to explain why its doing that and kept the modual as is (a.k.a. happy accident) _________________ home made noise and electronic ill-logic |
|
Back to top
|
|
|
tjookum
Joined: May 25, 2010 Posts: 360 Location: Netherlands
Audio files: 26
|
Posted: Mon Dec 13, 2010 11:37 am Post subject:
|
|
|
Hmm, asuming you grounded unused inputs, did you use a bypass capacitor?
It's common practice to have a 0.1 uF cap between the +V and grnd as close to the pins as possible. Personally I don't think it's needed for every IC, I just use them on oscillators and use a bigger one for an entire pcb of logic cmos. _________________ There he goes. One of God's own prototypes. A high-powered mutant of some kind never even considered for mass production. Too weird to live, and too rare to die.
Hunter S. Thompson
movies
noise |
|
Back to top
|
|
|
Team Toothpaste
Joined: May 06, 2010 Posts: 25 Location: London
|
Posted: Mon Dec 13, 2010 11:47 am Post subject:
|
|
|
@tjookum i use one across the pins of the i.c, usually in the nearest holes on the circuit board. but i've never put a larger one on the whole board. what size would you suggest? also should it go close to the battery connection? |
|
Back to top
|
|
|
tjookum
Joined: May 25, 2010 Posts: 360 Location: Netherlands
Audio files: 26
|
Posted: Tue Dec 14, 2010 2:15 am Post subject:
|
|
|
Quote: | what size would you suggest? also should it go close to the battery connection? |
Actually, Im not going to suggest anything . A big part of lunetta design is experimentation. Firstly because I don't know, I've only been doing this for 8 months or so and still very much in the learning process. Secondly, these subtle differences are very important in making your lunetta sound just that little bit different from all the others. I once made 4 oscillators with 2x lm556 and forgot the bypass cap. It sounded kind of strange and added just that edge of randomness I like. So I just put in a switch so I can choose to have it with or without the bypass cap and it's been a stable feature in a lot of my tracks. _________________ There he goes. One of God's own prototypes. A high-powered mutant of some kind never even considered for mass production. Too weird to live, and too rare to die.
Hunter S. Thompson
movies
noise |
|
Back to top
|
|
|
|