Datasheet

DS80C320/DS80C323 High-Speed/Low-Power Microcontrollers
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AC ELECTRICAL CHARACTERISTICS—DS80C323
18 MHz VARIABLE CLOCK
PARAMETER SYMBOL
MIN MAX MIN MAX
UNITS
External
Oscillator
0 18 0 18
Oscillator
Frequency
External
Crystal
1/t
CLCL
1 18 1 18
MHz
ALE Pulse Width t
LHLL
68 1.5t
CLCL
-15 ns
Port 0 Address Valid
to ALE Low
t
AVLL
16 0.5t
CLCL
-11 ns
Address Hold After
ALE Low
t
LLAX1
6 (Note 5) 0.25t
CLCL
-8 (Note 5) ns
Address Hold After
ALE Low for MOVX
WR
t
LLAX2
14 0.5t
CLCL
-13 ns
ALE Low to Valid
Instruction In
t
LLIV
93 2.5t
CLCL
-46 ns
ALE Low to PSEN Low
t
LLPL
4 0.25t
CLCL
-10 ns
PSEN Pulse Width
t
PLPH
118 2.25t
CLCL
-7 ns
PSEN Low to Valid
Instruction In
t
PLIV
87 2.25t
CLCL
-38 ns
Input Instruction Hold
After
PSEN
t
PXIX
0 0 ns
Input Instruction Float
After
PSEN
t
PXIZ
51 t
CLCL
-5 ns
Port 0 Address to Valid
Instruction In
t
AVIV1
128 3t
CLCL
-39 ns
Port 2 Address to Valid
Instruction In
t
AVIV2
139 3.5t
CLCL
-56 ns
PSEN
Low to Address Float
t
PLAZ
(Note 5) (Note 5) 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.