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phani New Member Offline Posts: 4 india	cmos i/o driver design Aug 05^th, 2009, 12:09am Hello all, I am new here. I want to know how a cmos i/o driver is designed for the given current specs and max. on resistance. it would be better if any body can explain the design procedure also using spice. Thanx, Phani.
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raja.cedt Senior Fellow Offline Posts: 1516 Germany	Re: cmos i/o driver design Reply #1 - Aug 5^th, 2009, 1:22am hi, i think nobody will give both..generally they give termination resistance at the driver....first you have to see how much swing your RX can detect and how much signal attenuation in channel...sum of these two will give the driver swing.....this swing is the drop across the termination resistance...... Thanks, Rajasekhar.
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phani New Member Offline Posts: 4 india	Re: cmos i/o driver design Reply #2 - Aug 5^th, 2009, 3:35am yes you r correct, If you see in case of SSTL min. Ioh and Iol are required so that min levels are provided to the RX after channel noise and max. ron is used to terminate the line. In this case how to design the driver to meet Ioh and Iol and ron values.
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raja.cedt Senior Fellow Offline Posts: 1516 Germany	Re: cmos i/o driver design Reply #3 - Aug 5^th, 2009, 9:42am hi, i didn't understand your terminology (like ioh,iol)..could you please explain? thanks, rajasekhar.
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phani New Member Offline Posts: 4 india	Re: cmos i/o driver design Reply #4 - Aug 27^th, 2009, 1:51am Ioh and Iol are source and sink currents respectively. JEDEC standard says to source and sink some minimum currents to meet the desired Vol and Voh values.
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ywguo

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Posts: 943
Shanghai, PRC

Re: cmos i/o driver design
Reply #5 - Sep 9^th, 2009, 8:45pm

Hi Phani,

Quote:

Posted on: Aug 27th, 2009, 1:51am
Ioh and Iol are source and sink currents respectively.
JEDEC standard says to source and sink some minimum currents to meet the desired Vol and Voh values.

Although I have not read JEDEC standard on SSTL. It seems that the answer is already in your own post. Just keep Ioh and Iol large enough to meet the minimum voh and maximum vol.

Yawei

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