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Altera_Forum
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15 years ago

Cyclone III – VCCIO of unused banks

Is it possible to power down the VCCIO voltage on unused banks in Cyclone III devices? If Yes that which banks can be power down and what I must to do – leave unconnected VCCIO or connect they to GND...
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Altera_Forum
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15 years ago

Handbook writes:

Pg. 258, 296 > “VCCIO for all I/O banks must be powered up during device operation”

Pg.174> “If the device is powered up from the power-down state, the VCCIO for all the I/O banks must be powered up to the appropriate level for the device to exit from POR.”

That is I must apply power on ALL Vccio. But!

But on pg.260 wrote > “POR monitors the VCCINT, VCCIO, and VCCA pins during power-on. … POR circuitry also ensures the VCCIO level of I/O banks 1, 6, 7, and 8 that contains configuration pins reach an acceptable level before configuration is triggered.”

That is may be sufficiently apply power on Vccio only of banks 1,6,7,8?

But on pg.174 wrote > “To begin configuration, the required voltages shown in Table 9–4 must be powered up to the appropriate voltage levels: VCCINT, VCCA, VCCIO for banks in which the configuration and jtag pins reside.”

For serial configuration modes used only banks 1 and 6 – may be sufficiently apply power only on Vccio of this banks (1 and 6)?

What is right?

Alexander