DS14285 Datasheet, PDF (18/25 Pages) Dallas Semiconductor – Real Time Clock with NV RAM Control

AC ELECTRICAL CHARACTERISTICS Over the operating range
PARAMETER
SYMBOL MIN TYP MAX
Cycle
t_CYC
225
DC
Pulse Width, DS/E Low or RD/ WR
PW_EL
115
High
Pulse Width, DS/E Low or RD/ WR
Low
PW_EH
80
Input Rise and Fall Time
R/ W Hold Time
t_R, t_F
30
t_RWH
10
R/ W Setup Time Before DS/E
t_RWS
10
Chip Select Setup Time Before DS,
t_CS
20
WR , or RD
Chip Select Hold Time
t_CH
0
Read Data Hold Time
t_DHR
10
50
Write Data Hold Time
t_DHW
0
Muxed Address Valid Time to AS/ALE t_ASL
30
Fall
Muxed Address Hold Time
t_AHL
10
Delay Time DS/E to AS/ALE Rise
t_ASD
20
Pulse Width AS/ALE High
PW_ASH
60
Delay Time, AS/ALE to DS/E Rise
t_ASED
35
Output Data Delay Time From DS/E or t_DDR
10
75
RD
Data Setup Time
Reset Pulse Width
IRQ Release from DS
t_DSW
60
t_RWL
5
t_IRDS
2
IRQ Release from RESET
t_IRR
2
DS14285/DS14287
UNITS NOTES
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
9
ns
µs
µs
µs
AC TEST CONDITIONS
Input Pulse Level: 0 to 3.0V
Input Rise/Fall Times: 5 ns
Input and Output Timing Reference Levels: 1.5V
OUTPUT LOAD Figure 5
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