Hi folks,
I am trying to hook up a Decoder/Demultiplexer in order to multiply the number of outputs from the microcontroler. Here is the schematic:
I supply 5V to VCC and to one of the input pins. However all the output pins (0-15) remain HIGH. I would expect that I should be reading LOW on pad X1? What am I missing here?
Here is the schematic:
https://drive.google.com/file/d/1JFEzVuFqPfwSiq9UFO76exCtmS09j-OX/view?usp=sharing
Please post the image HERE - I'm not going to download anything off site.
So the device is working as designed. From the description of the device:
Each or these 4-line-to-16-line decoders utilizes TTL circuitry to decode four binary-coded inputs into one of sixteen mutually exclusive outputs when both the strobe inputs G1 and G2 are low The demultiplexing function is performed by using the 4 input lines to address the output line passing data from one of the strobe inputs with the other strobe input low **When either strobe input is high all outputs are high **
missdrew:
Please post the image HERE -
It's a link to a web image. You do not need to download anything. "Insert an image" icon doesn't allow to post an image. It asks to provide a link to the picture. At least this is my understanding.
@steve_mcdonald
Well, I do not have anything connected to G1 and G2. I presume, they are low in such case ?
I do not have anything connected to G1 and G2. I presume, they are low in such case ?
Why would you expect this to be true? They are floating, so the state is not fixed at HIGH or LOW!
Connect them to GND and see if that helps.
Good point. Thanks !