MM74HC4049?

Started by KerryF, October 16, 2006, 04:20:15 PM

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KerryF

I just searched this but no results for this exact model.  Will it work instead of a CD4049UB_?

Datasheets:
MM74HC4049- http://www.fairchildsemi.com/ds/MM%2FMM74HC4049.pdf
CD4049UB_- http://www.fairchildsemi.com/ds/CD%2FCD4049UBC.pdf

Thanks.

mojotron

I would think that it would work. From the datasheet, it looks like it would work. However the MM74HC4049 can take a max of 7v VCC - so make sure that the reference design brings the supply volts down to below 7v.

As a side note, I have used mc14049 ICs and they work great...

KerryF

So in other words... The IC will be smoking and dead if 7v or more gets to it.  But that means that if the voltage getting to the IC is 7v then its bad... which still means Resistors can be used to protect it?  Is there a certain pin that I have to specifically protect, so that I can measure the voltage to that specific pin?

mojotron

Pin 1 - VSS - is where the +V is applied. Either you can use a 7V source, or make a voltage divider.