DS87C530_1 Datasheet, PDF (32/44 Pages) Dallas Semiconductor – EPROM/ROM Micro with Real Time Clock

AC ELECTRICAL CHARACTERISTICS
33 MHz
PARAMETER
SYMBOL MIN MAX
Oscillator Freq. (Ext. Osc.)
(Ext. Crystal)
1/t_CLCL
0
33
1
33
ALE Pulse Width
t_LHLL
40
Port 0 Address Valid to ALE Low
t_AVLL
10
Address Hold after ALE Low
t_LLAX1
10
ALE low to Valid Instruction In
t_LLIV
56
ALE Low to PSEN Low
t_LLPL
10
PSEN Pulse Width
t_PLPH
55
PSEN Low to Valid Instr. In
t_PLIV
41
Input Instruction Hold after PSEN
t_PXIX
0
Input Instruction Float after PSEN
t_PXIZ
26
Port 0 Address to Valid Instr. In
t_AVIV
71
Port 2 Address to Valid Instr. In
t_AVIV2
81
PSEN Low to Address Float
t_PLAZ
0
DS87C530/DS83C530
VARIABLE CLOCK
MIN
MAX
0
33
1
33
1.5t_CLCL-5
0.5t_CLCL-5
0.5t_CLCL-5
0.5t_CLCL-5
2.5t_CLCL-20
2t_CLCL-5
2t_CLCL-20
0
t_CLCL-5
3t_CLCL-20
3.5t_CLCL-25
0
UNITS
MHz
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
NOTES FOR AC ELECTRICAL CHARACTERISTICS:
All parameters apply to both commercial and industrial temperature range operation unless otherwise
noted. All signals rated over operating temperature. All signals characterized with load capacitance of 80
pF except Port 0, ALE, PSEN , RD and WR with 100 pF. Interfacing to memory devices with float times
(turn off times) over 25 ns may cause contention. This will not damage the parts, but will cause an
increase in operating current. Specifications assume a 50% duty cycle for the oscillator. Port 2 and ALE
timing will change in relation to duty cycle variation.
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