6169 - ispMACH4000: What is the difference between "LVCMOS33" and "LVCMOS33_5V"?
Description:
The I/Os in the ispMACH 4000 are split into two banks. Each bank has a separate I/O power supply. Inputs can support a variety of standards independent of the chip or bank power supply.
Outputs support the standards compatible with the power supply provided to the bank. Support for a variety of standards helps designers implement designs in mixed voltage environments.
In addition, 5 V tolerant inputs are specified within an I/O bank that is connected to VCCO of 3.0 V to 3.6 V for LVCMOS 3.3, LVTTL and PCI interfaces.
Solution:
I/O type of "LVCMOS33_5V" means that a 5V tolerant input for LVCMOS will be assigned by the software to a bank that has a 3.3V VCCO while the "LVCMOS33" I/O type, will assign the 3.3V tolerant input to 3.3V VCCO, a standard.
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