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Programmable clocks

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mmracing

Computer
Nov 16, 2005
8
I have the following clock requirements for my present design:
200 MHz LVDS
166 MHz LVDS
166 MHz LVDS
166 MHz LVCMOS
166 MHz LVCMOS
166 MHz LVCMOS
166 MHz LVCMOS
150 MHz LVDS
150 MHz LVDS
133 MHz LVDS
133 MHz LVDS
100 MHz LVCMOS
100 MHz LVCMOS

Multiple clocks on single ended and differential outputs. These chips also need to be programmable. I2c, JTAG or some type of serial bus. Since these freqs are fairly close I definitiely need multiple PLLs.

I've found a couple from ICS and IDT which I think are the same company now. Any help will be appreciated.

thanks
 
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Doesn't Maxim-ic/Dallas have addressable clock chips?

Why does your list have many duplications?
 
I'll check them out.

Because I have multiple places that need the same clock frequency.
 
Hope you're just going to run one clock thru a couple of buffers to drive your different 'places'.
 
I'd split this project in two pieces:
1: generate the different frequencies and, Yes, you'll need multiple PLLs.
2: look at the distribution issue. Several companies have zero-delay clock distribution ICs (eg, 1 input to 4 outputs)

Look to ON Semiconductor's web page, they have quite a lot of this stuff.
 
Thanks for the help fellas.

I'm in the process of looking at On Semis web-site and you're right that they have a lot of good stuff.

I got a response from IDT last night with a 5 chip solution. 2 clock generators and 3 distribution chips. It would be nice to do this with 1 or 2 chips but that's proving difficult.

Thanks again for your help benta and itsmoked.
 
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