
32
Altera Corporation
FLEX 8000 Programmable Logic Device Family Data Sheet
Timing Model
The continuous, high-performance FastTrack Interconnect routing
structure ensures predictable performance and accurate simulation and
timing analysis. This predictable performance contrasts with that of
FPGAs, which use a segmented connection scheme and hence have
unpredictable performance. Timing simulation and delay prediction are
available with the MAX+PLUS II Simulator and Timing Analyzer, or with
industry-standard EDA tools. The Simulator offers both pre-synthesis
functional simulation to evaluate logic design accuracy and post-
synthesis timing simulation with 0.1-ns resolution. The Timing Analyzer
provides point-to-point timing delay information, setup and hold time
prediction, and device-wide performance analysis.
Tables 8 through
11 describe the FLEX 8000 timing parameters and their
symbols.
Table 8. FLEX 8000 Internal Timing Parameters
Symbol
Parameter
tIOD
IOE register data delay
tIOC
IOE register control signal delay
tIOE
Output enable delay
tIOCO
IOE register clock-to-output delay
tIOCOMB IOE combinatorial delay
tIOSU
IOE register setup time before clock; IOE register recovery time after asynchronous clear
tIOH
IOE register hold time after clock
tIOCLR
IOE register clear delay
tIN
Input pad and buffer delay
tOD1
Output buffer and pad delay, slow slew rate = off, VCCIO = 5.0 V, C1 = 35 pF, Note (2) tOD2
Output buffer and pad delay, slow slew rate = off, VCCIO = 3.3 V, C1 = 35 pF, Note (2) tOD3
Output buffer and pad delay, slow slew rate = on, C1 = 35 pF,
tXZ
Output buffer disable delay, C1 = 5 pF
tZX1
Output buffer enable delay, slow slew rate = off, VCCIO = 5.0 V, C1 = 35 pF, Note (2) tZX2
Output buffer enable delay, slow slew rate = off, VCCIO = 3.3 V, C1 = 35 pF, Note (2) tZX3
Output buffer enable delay, slow slew rate = on, C1 = 35 pF,