DS80C320 Datasheet, PDF (27/40 Pages) Dallas Semiconductor – High-Speed/Low-Power Micro

DS80C320/DS80C323 High-Speed/Low-Power Microcontrollers
AC ELECTRICAL CHARACTERISTICS—DS80C323
PARAMETER
SYMBOL
18 MHz
MIN
MAX
VARIABLE CLOCK
MIN
MAX
Oscillator
Frequency
External
Oscillator
External
Crystal
1/t_CLCL
0
1
18
18
0
1
18
18
ALE Pulse Width
Port 0 Address Valid
to ALE Low
Address Hold After
ALE Low
Address Hold After
ALE Low for MOVX WR
ALE Low to Valid
Instruction In
ALE Low to PSEN Low
PSEN Pulse Width
t_LHLL
t_AVLL
t_LLAX1
t_LLAX2
t_LLIV
t_LLPL
t_PLPH
68
1.5t_CLCL-15
16
0.5t_CLCL-11
6
(Note 5) 0.25t_CLCL-8
(Note 5)
14
0.5t_CLCL-13
93
2.5t_CLCL-46
4
0.25t_CLCL-10
118
2.25t_CLCL-7
PSEN Low to Valid
Instruction In
t_PLIV
87
2.25t_CLCL-38
Input Instruction Hold
After PSEN
t_PXIX
0
0
Input Instruction Float
After PSEN
t_PXIZ
51
t_CLCL-5
Port 0 Address to Valid
Instruction In
t_AVIV1
128
3t_CLCL-39
Port 2 Address to Valid
Instruction In
t_AVIV2
139
3.5t_CLCL-56
PSEN Low to Address Float
t_PLAZ
(Note 5)
(Note 5)
UNITS
MHz
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
NOTES FOR DS80C323 AC ELECTRICAL CHARACTERISTICS
All parameters apply to both commercial and industrial temperature operation unless otherwise noted. Specifications to -40°C
are guaranteed by design and are not production tested. AC electrical characteristics assume 50% duty cycle for the oscillator,
oscillator frequency > 16MHz, and are not 100% production tested, but are guaranteed by design.
1. All signals rated over operating temperature at 18MHz.
2. All signals characterized with load capacitance of 80pF except Port 0, ALE, PSEN , RD , and WR at 100pF.
Note that loading should be approximately equal for valid timing.
3. Interfacing to memory devices with float times (turn off times) over 35ns may cause contention. This will not
damage the parts, but will cause an increase in operating current.
4. Specifications assume a 50% duty cycle for the oscillator. Port 2 timing will change with the duty cycle
variations.
5. Address is held in a weak latch until over-driven by external memory.
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