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PINOUT ON 4558.

Started by mcasey1, November 13, 2006, 09:43:47 AM

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mcasey1

What are the pins (1-8) on a 4558 from this angle?


wampcat1

Quote from: mcasey1 on November 13, 2006, 09:43:47 AM
What are the pins (1-8) on a 4558 from this angle?



http://www.diystompboxes.com/wiki/index.php?title=DIY_FAQ

Here's the pinout for dual op amps such as the TL072, JRC4558:

http://www.diystompboxes.com/pedals/ampins.GIF

Dual Op Amps have this pinout (TL072, JRC4558).

Referring to the IC in schematic picture above, the wire going into the minus sign is the InvertedInput/pin 2. The wire going into the plus (+) sign is the Non-InvertedInput/pin 3. Vcc refers to the Vcc (+) input /pin 8. The groundgoes to Vcc(-)/pin 4. The wire exiting the IC in schematic is the Output /pin 1. Since the TL072 is a dual op amp, there are two sets of Input and Outputs. Sometimes circuits will use both amps (inputs and outputs), sometimes it will use only one set. In both cases, Vcc(+) and Vcc(-) will have to be connected. Vcc(+)goes to positive power. Vcc(-) goes to ground. If only one of the op amps are used, the other set of inputs and outputs can be left disconnected. In some schematics, the Vcc(+) (power) and Vcc(-) ground will not be shown. This does not mean you don'thave to connect these pins, you have to; the schematic writer is assuming you already know this..


MikeH

"Sounds like a Fab Metal to me." -DougH

Mark Hammer

Although I suppose there are always exceptions to everything, I can't recall a single chip of the tens of thousands I have stared at for one reason or another where the chip information did NOT run from left to right starting from the junction between pins 1 and 8.  That "starting point" is most often indicated by a slight indent between those two pins, but is also often indicated by a small dot-like depression beside pin 1.  Sometimes there might be some white inside the depression to help identify it, and sometimes there isn't and you just have to hold it up to the light to see the little dent.

So, whether the writing/information, the indent in between pins 1 and N (8, 14, 16, 18, 24, etc., or however many pins the DIP chip has), or the dent beside pin 1, you will always be able to identify pin 1.