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Altera_Forum's avatar
Altera_Forum
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15 years ago

DEo NANO VCC noise

hi i have a de0 nano and in the gpio headers i am doing pwm at 50MHZ...it have 2 gpio headers of 40 pins .. and i notice that when they are the same ... in the VCC_SYS appear a noise almost 2 Vpp... ...
Altera_Forum's avatar
Altera_Forum
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15 years ago

i am using pckey CMOS OCTAL BUS BUFFERS(tc74hc541ap)...each PWM FROM THE BOARD IS THE INPUT OF EACH PIN OF THE BUFFERS. the buffer have 10 pF of input capacitence per pin i think.

but when i try to do it without the buffers(just the board, nothing else) the same thing happen.. there was the noise in VCC_SYS...