🚀 go-pugleaf

Fred Bloggs wrote:
> 
> 
> John Williams wrote:
> 
>> John Larkin <jjlarkin@highlandSNIPtechTHISnologyPLEASE.com> wrote in 
>> message
>>
>>> <jwilliams@itee.uq.edu.au> wrote:
>>>
>>>
>>>> I'm looking for a 2.5V, 100MHz clock source, preferably in a surface 
>>>> mount package.  Any part or supplier suggestions?
>>>>
>>>> 2.5V operation is my highest priority.  Existence of an Australian 
>>>> supplier would also be helpful!
>>>
>>>
>>
>>> Um, how accurate? 
>>
>>
>>
>> Well I'm not measuring the speed of light - but +/- 100ppm or so would
>> be good.
>> For any future critical time keeping applications I could use an RTC
>> chip or whatever.
>>  
>>
>>> Must it be a crystal oscillator?
>>
>>
>>
>> Not necessarily - just simple and stable - basically just solder it in
>> and off I go...
>>
>>
>>> Why 2.5 volts? Clocking an FPGA or something?
>>
>>
>>
>> Precisely - and the IO bank onto which this clock comes is driving
>> some 2.5V DDR, so I don't have a lot of room to manoeuvre.
>>
>> The FPGA is actually hosting a soft core microprocessor (running our
>> linux port no less!), so I'm just generating a processor clock with
>> it.  The FPGA has a digital clock synthesiser inside it that I could
>> use, but I'd prefer not to "waste" one if I don't need to (since the
>> DDR drive logic needs a couple as well).
>>
>> But I should ask...  what are my options for simple and stable 2.5V
>> oscillators and lower frequencies (24Mhz, 66Mhz, ...)??
>>
>> Thanks,
>>
>> John
> 
> 
> This will do it:
> 
> http://www.eea.epson.com/go/Prod_Admin/Categories/EEA/QD/SAW_Products/SAW_Oscillators/displayItem?itemId=EG2021CA&categoryId=EEA.QD.SAW_Products.SAW_Oscillators 
> 
> 
> -or-
> 
> http://www.eea.epson.com/go/Prod_Admin/Categories/EEA/QD/SAW_Products/SAW_Oscillators/go/Resources/TestC2/EG2021CA 

I just noticed that these devices are due for mass production in Spring 
2004, given the small numbers we'll be wanting, I wouldn't expect to get 
some any time soon.

So, falling back to al ower frequency, but still on 2.5V.. It is stated 
explicitly in the Xilinx data sheets not to drive an input above it's 
rated voltage - so I'm not happy about using a 3.3V clock.

So, any 2.5V oscillators at 25-66Mhz?

Thanks,

John