
Chapter 1: Cyclone IV Device Datasheet
1–37
I/O Timing
December 2013
Altera Corporation
I/O Timing
Use the following methods to determine I/O timing:
■
the Excel-based I/O Timing
■
the Quartus II timing analyzer
The Excel-based I/O timing provides pin timing performance for each device density
and speed grade. The data is typically used prior to designing the FPGA to get a
timing budget estimation as part of the link timing analysis. The Quartus II timing
analyzer provides a more accurate and precise I/O timing data based on the specifics
of the design after place-and-route is complete.
Glossary
Table 1–46. Glossary (Part 1 of 5)
Letter
Term
Definitions
A
——
B
——
C
——
D
——
E
——
F
fHSCLK
High-speed I/O block: High-speed receiver/transmitter input and output clock frequency.
G
GCLK
Input pin directly to Global Clock network.
GCLK PLL
Input pin to Global Clock network through the PLL.
H
HSIODR
High-speed I/O block: Maximum/minimum LVDS data transfer rate (HSIODR = 1/TUI).
I
Input Waveforms
for the SSTL
Differential I/O
Standard
V
IL
V
REF
V
IH
VSWING