Oh, ok.. I guess I was thinking xtal1 would
output.. instead of input..
So that is why the pin8 on the crystalclock
oscillator would be hooked directly up to xtal1.
So what would I do with xtal2? Leave it
unconnected?
thanks
Lee
----- Original Message -----From: Kathy QuinlanSent: Monday, July 04, 2005 7:02 PMSubject: Re: [AVR-Chat] What crystals/resonators do you'll use?Pigeon wrote:
> Hmm.. because I would rather have something super simple.. and high
> quality, I like the idea of the
> crystal clock oscillator
> http://rocky.digikey.com/WebLib/Epson/Web%20Data/SG-51,531%20Series.pdf
>
> but my question is.
> I see
> pin1: 0E
> pin7: GND
> pin8: OUT
> pin14: Vdd
>
> but what pins go to what? (do I need any external caps/resistors)
>
>; I have seen a schematic that had xtal 1 go to the crystal clock
> oscillator.. then xtal2 go to another avr's xtal 1.. but that isn't what
> i want.
>
> I guess the pdf of this schematic expects an expert to be reading it :/
>
>
> what do you'll think?
>
> Lee
The ones I use (from Radio Spares in Au (only as I needed 2 and they
deliver ;))
Pin 1 is No Connection
Pin 7 is Ground
Pin 8 is Output
Pin 14 is Vcc
Not all the modules have the inverted output, some even have just a
buffer so that it can drive 2 loads.
All you need for most apps is Pins 7,8,14 and leave pin 1 open circuit.
The only special attention I give them is a 10uF electro and a 0.1uF
mono caps as close as possible (the mono is usually on the bottom as I
do mainly SMD these days.
In most products I design I have 2 versions, 1 uses a crystal, and the
other the internal oscillator. but unless it is a package that can have
its crystal pins used as IO, then I tend to wack a crystal in with the
two caps (it only adds au$1 to the product cost) and I am not making
100's of these, most runs are bellow 20.
Regards,
Kat.