DS17285 Datasheet, PDF (27/38 Pages) Dallas Semiconductor – 3V/5V Real-Time Clock

RTC AC TIMING CHARACTERISTICS
PARAMETER
SYMBOL MIN
Cycle Time
t_CYC
360
Pulse-Width, RD / WR Low
PW_RWL
200
Pulse-Width, RD / WR High
PW_RWH
150
Input Rise and Fall
t_R, t_F
Chip-Select Setup Time
Before WR or RD
t_CS
20
Chip-Select Hold Time
t_CH
0
Read Data Hold Time
t_DHR
10
Write Data Hold Time
t_DHW
0
Muxed Address Valid Time to
ALE Fall
t_ASL
40
Muxed Address Hold Time to
ALE Fall
t_AHL
10
RD or WR High Setup to
ALE Rise
Pulse-Width ALE High
t_ASD
30
PW_ASH
40
ALE Low Setup to RD or WR
Fall
t_ASED
30
Output Data-Delay Time from
t_DDR
20
RD
Data Setup Time
t_DSW
70
IRQ Release from RD
t_IRD
AC TEST CONDITIONS
Output Load: 50pF
Input Pulse Levels: 0V to 3.0V
Timing Measurement Reference Levels
Input: 1.5V
Output: 1.5V
Input Pulse Rise and Fall Times: 5ns
DS17285/DS17287
Over the operating range (3V)
TYP MAX UNITS NOTES
DC
ns
ns
ns
30
ns
ns
ns
90
ns
ns
ns
ns
ns
ns
ns
200
ns
6
ns
2
ms
27 of 38