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Altera_Forum
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14 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
Icon for Honored Contributor rankHonored Contributor
14 years ago

Did you connect a load to VCC? Then it may be a problem of missing bypass capacitors. If the pwm signal is driving a large capacitance, e.g. a MOSFET, the ground wire inductance can cause respective ground bounce.