Trying to identify a chip...

Nov 17, 2009 6 Replies
D

Suspect it is a MC145155-2 in the 18-pin DIP package. Datasheet for this chip shows pin 5 as VDD, and I am wondering, isn't VDD usually the same as GND? (Don't see any pins labled as GND, although there is VSS ,which I am thinking is +5 volts). Any help is appreciated...



Thanks,



Dave


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D

Forgot to mention, the 145155-2 is the 18-pin DIP version of a (common?) Phase-Locked Loop.

Thanks again.

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J

No, it's the supply voltage.
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D

Hah. So I had it backwards. VDD is supply voltage, and VSS is GND. Damn. Glad I asked.

Thanks much!

Dave

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J

You're welcome. :-) One thing... On these electronics groups it's customary to crosspost instead of multi-posting in that all of the replies will appear in all the groups when the reply is made in _any_ of the groups. Makes it much easier to follow the thread and not have to post individual replies in each group. JF
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M

Think in terms of "drain" and "source". For an n-channel FET, the drain goes to the positive supply, the source goes to ground.

Michael

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D

Yeah, sorry. I'm a DIP (and that is not dual inline package.) Will try to do better...

Dave

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