New user frustrated - can't find part  :(

Am 25.08.2011 08:13, schrieb Steve Klett:

but the pin labels don't match what I'm expected (specifically, where is /E and /LE?)  The part in eagle has /ST and /INH

A lot of parts are available from MORE than one manufacturer, and,

unfortunately, these sometimes name their component pins differently:

E.g., the pin called LE ('latch enable') might be called /INH ('inhibit

not') by some other manufacturer. Without looking into the data sheets,

it's sometimes tricky to get to know whether things are compatible or

not. This might or might not be the case with your IC, but at least it's

something you should be aware of.

Andreas Weidner

Hi, thanks for the reply.  I realize there are multiple manufacturers but wasn't aware they would use different pin identifiers.

Interesting - I just did a digikey search for "HC4514" to get a list of some manufacturers to include in this response.  I noticed fairchild down at the bottom and checked out their datasheet.  And hey! - they use "strobe" for /LE and "Inhibit" for /E (assuming they are pin compatible)

You mention "Inhibit not" which I still need to read up on because the datasheet just says "inhibit"  From reading the datasheet it sounds like the outputs will respond to the inputs when the inhibit is LOW, so maybe this is what "inhibit not" means; "inhibit low"?

Anyway, thanks for the response and information.

Hi, thanks for the reply.  I realize there are multiple manufacturers but wasn't aware they would use different pin identifiers.

Interesting - I just did a digikey search for "HC4514" to get a list of some manufacturers to include in this response.  I noticed fairchild down at the bottom and checked out their datasheet.  And hey! - they use "strobe" for /LE and "Inhibit" for /E (assuming they are pin compatible)

You mention "Inhibit not" which I still need to read up on because the datasheet just says "inhibit"  From reading the datasheet it sounds like the outputs will respond to the inputs when the inhibit is LOW, so maybe this is what "inhibit not" means; "inhibit low"?

Anyway, thanks for the response and information.

Am 26.08.2011 03:40, schrieb Steve Klett:

You mention "Inhibit not" which I still need to read up on because the datasheet just says "inhibit"  From reading the datasheet it sounds like the outputs will respond to the inputs when the inhibit is LOW, so maybe this is what "inhibit not" means; "inhibit low"?

Yes that means low level active Unfortunately, as you have found

out, different manufacturers use different identifiers. So one must

compare the pin numbers. You see for cadsoft it is not so easy to hit

the "correct" identifier, since there is none. It just depends what

datasheet they used.

(The source is sometimes mentioned in the description of a device).

I have more than 4000 datasheets and still have to check a douzen or so

against other manufacturers because those sheets contain insufficient

information.

--

Mit freundlichen Grüßen / With best regards

Joern Paschedag

Am 26.08.2011 03:40, schrieb Steve Klett:

And hey! - they use "strobe" for /LE and "Inhibit" for /E (assuming they are pin compatible)

For digital ICs, one VERY often names a pin after its function, assuming

that this function is activated by a logic '1' signal.

E.g., the input pin 'EN' might mean 'enable' and usually enables some

functionality if connected to a logic '1'. If this function were

activated by a logic '0', the pin would often be called 'EN\' or '/EN'

or something like that (or, even nicer, would contain an overstrike,

which now can be done in EAGLE by using '!EN').

Depending on your view of the world, the same function could therefore

be called either 'EN' (enabled with a logic '1') or '/DIS' (disabled

with a logic '0'),...

In your case, it would be '/E' (enabled with a logic '0') and 'INH'

(inhibited or disabled with a logic '1'), which is essentially the same.

However this may be, you can never fully rely on it, and always should

risk a look into the data sheet.

Andreas Weidner

Guest wrote:

 

...(The source is sometimes mentioned in the description of a device). ...

 

I've come across this on a few parts avnd immediately appreciated it.  I have created a few parts (8 resistor SOIC array and Clare CPC1014 SSR) and added links to the parts, manf. info and PN.  If everyone did this (where applicable) it would be nice 

Guest wrote:

 

... something like that (or, even nicer, would contain an overstrike,

which now can be done in EAGLE by using '!EN').

 

 

Cool, good tip, thanks!  I like the overstrike notation.  Also your advice to check the datasheet is good advice, thanks.

Steve Klett schrieb:

Guest wrote:

>

> ..(The source is sometimes mentioned in the description of a device).

> ...

I've come across this on a few parts avnd immediately

appreciated it.  I have created a few parts (8 resistor SOIC array

and Clare CPC1014 SSR) and added links to the parts, manf. info and

PN.  If everyone did this (where applicable) it would be nice

You should really consider using a newsreader or at least a working

gateway to access these newsgroups. These posts via element14 are

horrible to read.

If you prefer web access, please have a look at eaglecentral.ca.

Tilmann