DS80C310_09 Datasheet, PDF (13/22 Pages) Dallas Semiconductor – High-Speed Microcontroller

DS80C310
AC ELECTRICAL CHARACTERISTICS (Note 1)
PARAMETER
Oscillator
Frequency
External Oscillator
External Crystal
SYMBOL
1/t_CLCL
25MHz
MIN
0
1
MAX
25
25
ALE Pulse Width
t_LHLL
40
Port 0 Address Valid to ALE Low
t_AVLL
10
Address Hold after ALE Low
t_LLAX1
2 (Note 2)
ALE Low to Valid Instruction In
t_LLIV
56
ALE Low to PSEN Low
PSEN Pulse Width
PSEN Low to Valid Instruction In
Input Instruction Hold after PSEN
Input Instruction Float after PSEN
t_LLPL
7
t_PLPH
55
t_PLIV
41
t_PXIX
0
t_PXIZ
26
Port 0 Address to Valid Instruction In
t_AVIV1
71
Port 2 Address to Valid Instruction In
PSEN Low to Address Float
t_AVIV2
t_PLAZ
81
(Note 2)
VARIABLE
CLOCK
MIN MAX
0
25
1
25
1.5t_CLCL-
5
0.5t_CLCL-
5
0.5t_CLCL-
18
0.5t_CLCL-
13
(Note 2)
2.5t_CLCL-
20
2t_CLCL-5
2t_CLCL-
20
0
t_CLCL-5
3t_CLCL-
20
3.5t_CLCL-
25
(Note 2)
UNITS
MHz
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
Note 1:
Note 2:
All parameters apply to both commercial and industrial temperature operation unless otherwise noted. Specifications to -40C
are guaranteed by design and not product tested. AC electrical characteristics assume 50% duty cycle for the oscillator, and
are not 100% tested but are guaranteed by design. All signals characterized with load capacitance of 80pF except Port 0, ALE,
PSEN, and WR with 100pF. Interfacing to memory devices with float times (turn-off times) over 25ns can cause contention.
This does not damage the parts, but rather causes an increase in operating current. Port 2 and ALE timing changes in relation
to duty cycle variation.
Address is held in a weak latch until overdriven by external memory.
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