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ben heck a/v selector, alternate chips Answered

Hey guys, I am about to set out and create Ben Heck's A/V selector.  http://www.engadget.com/2007/03/13/how-to-make-a-solid-state-a-v-switcher/

He uses a bus switch, CBT3244A, Digi-Key part # 568-3619-5-ND (out of stock I believe).  While I could order a comparable bus switch, I have several lying around from hacking apart a kid's toy.  74hc374.

I've looked at the datasheets and, I've never been very adept at understanding them, preferring the lazymans terms.  I understand that the original chip has 2 switches (to use for two separate a/v connections, or turning both on for a connection with more pins) while the chip I have has only one switch, allowing up to 8 channels to go through.

What I'm confused about is the state of the "on" switch for the one I have, or maybe the clock.  From what I understand, they each need to be pulled LOW (connected to ground) in order for their respective inputs to flow through, can the clock, in my case, be ignored?

For the arduino tags, I do plan to make this project remote controlled.  But I'm a serious beginner in this area.  Basically I plan to replicate this project for arduino.  http://www.tauntek.com/tinyir2-learning-ir-remote-control-receiver.htm  Would there be a point to that?  Or would it be simpler to just order the chip by itself already programmed.  I think that programmed tinyir2 PIC chip and arduino chips come out around the same price wise.  I have the other components lying around already.

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user
steveastrouk (author)2011-12-28

The 374 is NOT an alternative to the CBT3244

Steve

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user

How so? If the Arduino can be included in the project, it can probably handle the clock part. Or is it something else?

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user

The CBT3244 is being used as an analog switch from what I can discern of the original link. The 374 is a DIGITAL bus switch.

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user

ah ok. Could I use them for an led matrix then?

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user

They haven't got the output drive for a matrix display. Try ULN 2803.

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