Hello ,
I just started to play around with the digital realm and I got myself some basic gates .
I'm trying to connect this NAND gate I have ( SN7438AJ ) and play around with it but it's not working as it's supposed to be .
***
First of all in the datasheet it says that it's a quad 2-input NAND buffer . I know what a buffer is , but does that mean that I can use this IC as a normal NAND and that it's simply buffered for more current sinking/sourcing capability? Or does this IC need a normal NAND IC to function?
***
It also says that it's 'open collector' . I checked out some schematics to see what they mean but I cannot get a satisfying explanation in terms of how I should connect the gate (any advice would be appreciated) .
Also do I need pull-up/down resistors (why ? ) on the inputs/outputs for the gate to function properly?
The reason that I'm asking is because I'm trying to connect the gate and make it work but the gate is behaving like an 'AND' gate instead of 'NAND'
I've tried connecting an LED through a resistor with the positive terminal hooked to + voltage and negative to the output of the first gate and the LED lights up when both inputs are high and off otherwise (that's an 'AND' function right? )
I can't find any sources on the net that would explain practical wiring of Logic gates , I'd be very gratefull if someone pointed me in the right direction
Datasheet of the IC i'm using :
http://www.home.hs-karlsruhe.de/~bebe0001/74LSXX/7438.pdf
I just started to play around with the digital realm and I got myself some basic gates .
I'm trying to connect this NAND gate I have ( SN7438AJ ) and play around with it but it's not working as it's supposed to be .
***
First of all in the datasheet it says that it's a quad 2-input NAND buffer . I know what a buffer is , but does that mean that I can use this IC as a normal NAND and that it's simply buffered for more current sinking/sourcing capability? Or does this IC need a normal NAND IC to function?
***
It also says that it's 'open collector' . I checked out some schematics to see what they mean but I cannot get a satisfying explanation in terms of how I should connect the gate (any advice would be appreciated) .
Also do I need pull-up/down resistors (why ? ) on the inputs/outputs for the gate to function properly?
The reason that I'm asking is because I'm trying to connect the gate and make it work but the gate is behaving like an 'AND' gate instead of 'NAND'
I've tried connecting an LED through a resistor with the positive terminal hooked to + voltage and negative to the output of the first gate and the LED lights up when both inputs are high and off otherwise (that's an 'AND' function right? )
I can't find any sources on the net that would explain practical wiring of Logic gates , I'd be very gratefull if someone pointed me in the right direction
Datasheet of the IC i'm using :
http://www.home.hs-karlsruhe.de/~bebe0001/74LSXX/7438.pdf
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