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Altera_Forum
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16 years ago

FPGA drive current effect on power draw in Cyclone IV

Howdy, With the Cyclone IV FPGA, we have run into some issues with noise on Vccio and Vccint pins while using the 24 mA default drive current. I found an application note (http://www.altera.co...
Altera_Forum's avatar
Altera_Forum
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16 years ago

With Cyclone II, the most likely failure mechanism is PLL unlocking caused by ground bounce or switching "noise" affecting VCCA. It's particularly a problem with PQFP packages and it's huge pin inductances. If lower drive strength doesn't help, reduction of simultanous switching outputs may be the only solution.