S1K50000 Epson Electronics America, Inc., S1K50000 Datasheet - Page 78

• Manufacturer Part Number: S1K50000
• Description: Design Guide S1k50000 Series
• Manufacturer: Epson Electronics America, Inc.

5.8 Differentiating Cell Usage
5.9 Intra-Chip Skew
STANDARD CELL S1K50000 SERIES
DESIGN GUIDE
(1) Cells with names suffixed by *P, *V, *O, *X2, or *X3
(2) Cells with names suffixed by *C or *X0
Inside an LSI, due to varying transistor characteristics between lots or makes and other
reasons, tpd varies even for the same type of gate. Therefore, tpd may have relative drifts
between multiple signals. This is known as the “skew.” This skew may make it impossible for
the setup or hold time to be met. Take this skew into consideration in the design of a circuit, to
ensure a sufficient timing allowance.
The intra-chip skews in the S1K50000 series are listed in Table 5-5 below.
These cells have enhanced drive capability compared to that of ordinary cells.
These cells have reduced drive capability compared to that of ordinary cells.
Internal cell
I/O cell
Cell
Table 5-5 Intra-Chip Skew
All areas
All areas
Location
EPSON
Chapter 5: Propagation Delay Time and Timing Design
Skew
5%
5%
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