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Altera_Forum
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11 years ago

Disabling PLL for Cyclone III

I am working to design a Cyclone III FPGA powered off of a 1.5 V battery. As I research powering all different parts of the FPGA, it looks like most output/input buffers etc. are receptive to this lo...
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Altera_Forum
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11 years ago

Powering the VCCA pins at 1.5V will clearly be out of spec. However, more importantly, the configuration process will not start until the correct voltages are detected on certain pins. This includes the VCCA pins. So, you're FPGA will not work unless VCCA is within spec.

Read the Configuration Process section on page 9-8 of the configuration, design security, and remote system upgrades in the cyclone iii device family (http://www.altera.com/literature/hb/cyc3/cyc3_ciii51016.pdf).

I trust you were not proposing to power the VCCINT pins at 1.5V...?

Cheers,

Alex