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ANBARASU's avatar
ANBARASU
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11 months ago

CYCLONE V FPGA POWER-UP SEQUENCE

Currently i am using the below cyclone V FPGA for my design, Part: 5CGTFD7D5F27I7N As per the CV-52001 (2023.10.18) -Volume 1: Device Interfaces and Integration The recommended power-up sequence g...
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Farabi's avatar
Farabi
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11 months ago

Hello,


The current transient of VCCPD meaning here is the sudden inrush current happening to the VCCPD and from voltage perspective, you will observe a voltage spike(likely a voltage ripple) if you dont follow the power up sequence. If this voltage spike shoot up above the maximum limit of the allowable operating condition of the VCCPD voltage, the POR circuitry will put the device back to reset mode and re-run the power cycle again. This process will be continuous until the voltage satisfied all the operating parameters defined in datasheet. It is important to power up all the power rails in Group 1 first, followed by Group 2 to avoid this kind of failure.


The maximum current transient will be ~1000mA for at least 50us will happen if you dont follow the power up sequence. You may need to add decoupling capacitors to smoothen the current transient if you dont follow the power up sequence. So to avoid this, it is recommended to follow the power up sequence as mention in user guide.


regards,

Farabi