Author Topic: Ic suffix  (Read 1435 times)

klonisgayjplay

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Ic suffix
« on: January 03, 2017, 01:10:26 PM »
I already bought all my ic's so it's really too late. But when you're shopping for an ic can you buy ic's that aren't the exact on the build of materials? Like instead of jrc4885 it's jrc4885ce. I made this example up, if my question is unclear please let me know and I'll search my orders for a specific example.

devilsnight

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Re: Ic suffix
« Reply #1 on: January 03, 2017, 10:53:49 PM »
The 4558 for example could be a 4558M (surface mount) or 4558D (Dual 8 pin) so that matters quite a bit. The prefix is the supplier, RC4558 (texas inst.) NJM4558 (new japan radio) etc... Different manufactures may sound different also. It is best to check the data sheet so you know what your buying! If you bought NJM4558's instead of JRC4558's no problem. Some say the JRC4558 is a better sounding chip, maybe why they specify the JRC.
« Last Edit: January 03, 2017, 10:56:27 PM by devilsnight »

BrianS

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Re: Ic suffix
« Reply #2 on: January 04, 2017, 09:04:44 AM »
I'm not an expert on this by any means but often another 8 pin IC can be substituted i.e., TL071 or 72, NE5532, OPA2134PA, etc.... in some builds.  Many times the build doc will tell you that.  Checking the data sheet as said above will ensure the IC is working like the build doc IC.  My best advice is you should always socket any IC you put on a board. Trying to desolder an IC from a board is normally going to lead to 2 things, a burnt IC and/or a burned up board. 

midwayfair

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Re: Ic suffix
« Reply #3 on: January 04, 2017, 09:28:32 AM »
Datasheets tell you what the letters at the end mean.

You're likely to look at them and say to yourself "Why should I care?"
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klonisgayjplay

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Re: Ic suffix
« Reply #4 on: January 05, 2017, 12:14:14 PM »
Yeah from now on I'm reading data sheets. I have a nautilus from a few years back I finally wired up that isn't working and it makes me realize I've been a little carefree with the way I've been building. Jon just want to thank you for your YouTube channel, it's super helpful and encouraging.

stringsthings

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Re: Ic suffix
« Reply #5 on: January 05, 2017, 12:31:39 PM »
Just make sure you get the right package.  For 99% of pedal builds, this will be DIP - dual inline package or PDIP - plastic dual inline package.
These indicate that the part is for through hole mounting which we want.
You don't want a surface mount package. ( ex. SO-#, SOIC-#,  SOP-#, ... )
Some of the other suffixes are for the how the chips are bundled.  ( ex. reel, tape, bulk )

Try searching for a common chip like a TL072 on the Mouser site.
You'll see a bunch of matches with pictures on the left of the different packages.
Op amps like the TL072 are used all over the place in the in the pedal work.
The datasheets are pretty informative and not all that weird once you get to know your way around them.

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klonisgayjplay

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Re: Ic suffix
« Reply #6 on: January 05, 2017, 02:46:21 PM »
Which leads me to my next question. When A pedal doesn't work what parts should I start debugging first? I'm sure this is very wrong of me but this is what I imagine to be the scale of fragility from most fragile to least fragile. Ic's, transistors/mosfets, diodes, capacitors, resistors.

ShredderNemo

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Re: Ic suffix
« Reply #7 on: January 05, 2017, 04:07:12 PM »
You would want to check your own work before anything. Every time I've had an issue come about it was a result of an error I made. Most of my mistakes have been:

Solder bridges (they can be tucked away, or really unnoticeable in some cases), poor connections or solder joints, a forgotten ground connection, transistor orientation/placement, wiring mistakes, or a component grounding out against an enclosure.

Hope this helps!

stringsthings

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Re: Ic suffix
« Reply #8 on: January 05, 2017, 04:54:20 PM »
Which leads me to my next question. When A pedal doesn't work what parts should I start debugging first? I'm sure this is very wrong of me but this is what I imagine to be the scale of fragility from most fragile to least fragile. Ic's, transistors/mosfets, diodes, capacitors, resistors.

Components rarely go bad.  As ShredderNemo said, most problems can be traced back to soldering issues. 

There are several schools of thought when it comes to trouble-shooting.  I like to start by checking that power is getting to the right places and then check that the circuit grounds are in the right place.  The schematic of the circuit will give you this important information.  Since many pedal circuits use a 9V power supply, you can use your DMM to verify that the correct places are getting 9V ( or very close to 9V ).  Some circuits use what is called a bias voltage that is usually 1/2 of the supply voltage; in this case, that would be 4.5V.  So there would be another voltage to check. 

After that, using some sort of audio probe can lead you to where the fault might be.   Or you could the continuity function on your DMM ( you do have one, right ? ) to check connections between parts. 
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