Preliminary – Intel 8XC251SA User Manual
Page 20

20
PRELIMINARY
8XC251SA/SB/SP/SQ HIGH-PERFORMANCE CHMOS MICROCONTROLLER
T
RLRH
(2)
RD# or PSEN# Pulse Width
@ 12 MHz
@ 16 MHz
146.6
105
2(1+N)
T
OSC
– 20
ns
T
WLWH
WR# Pulse Width
@ 12 MHz
@ 16 MHz
146.6
105
2(1+N)
T
OSC
– 20
ns
T
LLRL
ALE Low to RD# or PSEN# Low
@ 12 MHz
@ 16 MHz
58.3
37.5
T
OSC
– 25
ns
T
LHAX
ALE High to Address Hold
@ 12 MHz
@ 16 MHz
83.3
62.5
(1+2M)T
OSC
ns
T
RLDV
(2)
RD#/PSEN# Low to valid Data/Instruction In
@ 12 MHz
@ 16 MHz
106.6
65
2(1+N)
Tosc – 60
ns
(4)
T
RHDX
(2)
Data/Instruction Hold Time. Occurs after
RD#/PSEN# are exerted to V
OH
0
0
ns
T
RLAZ
RD#/PSEN# Low to Address Float
Typ.=0
(5)
2
Typ. = 0
(5)
2
ns
T
RHDZ
1
Instruction Float after RD#/PSEN# High
commercial @ 12 MHz and 16 MHz
express @ 12 MHz and 16 MHz
Typ.=2
5
Typ.=2
5
(5)
18
10
Typ.=25
Typ.=25
(5)
18
10
ns
T
RHDZ
2
Data Float after RD#/PSEN# High
@ 12 MHz
@ 16 MHz
156.6
115
2Tosc – 10
ns
T
RHLH
1
RD#/PSEN# High to ALE High (Instruction)
@ 12 MHz
@ 16 MHz
10
10
10
ns
T
RHLH2
RD#/PSEN# High to ALE High (Data)
@ 12 MHz
@ 16 MHz
156.6
115
2T
osc
- 10
ns
T
WHLH
WR# High to ALE High
@ 12 MHz
@ 16 MHz
171.6
130
2T
osc
+ 5
ns
Table 11. AC Characteristics (Continued)
Symbol
Parameter
@ Max F
osc
(1)
F
osc
Variable
Units
Min
Max
Min
Max
NOTES:
1.
16 MHz.
2.
Specifications for PSEN# are identical to those for RD#.
3.
In the formula, M=Number of wait states (0 or 1) for ALE.
4.
In the formula, N=Number of wait states (0,1,2, or 3) for RD#/PSEN#/WR#.
5.
“Typical” specifications are untested and not guaranteed.