DS1685 Datasheet, PDF (27/33 Pages) Maxim Integrated Products – 3V/5V Real-Time Clocks

RTC AC TIMING CHARACTERISTICS
(V_CC = 5.0V±10%, T_A = 0°C to +70°C, T_A = -40°C to 85°C.)
PARAMETER
SYMBOL
MIN
Cycle Time
Pulse Width, RD/WR Low
Pulse Width, RD/WR High
Input Rise and Fall Time
Chip-Select Setup Time
Before WR or RD
t_CYC
195
PW_RWL
75
PW_RWH
75
t_R, t_F
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
30
Muxed Address Hold Time
from ALE Fall
t_AHL
15
RD or WR High Setup to ALE
Rise
t_ASD
25
Pulse-Width ALE High
PW_ASH
40
ALE Low Setup to RD or WR
Fall
t_ASED
30
Output-Data Delay Time from
RD
t_DDR
20
Data Setup Time
IRQ Release from RD
t_DSW
60
t_IRD
AC TEST CONDITIONS
Output Load: 50pF
Input Pulse Levels: 0 to 3.0V
Timing Measurement Reference Levels
Input : 1.5V
Output: 1.5V
Input Pulse Rise and Fall Times: 5ns
DS1685/DS1687 3V/5V Real-Time Clocks
TYP
MAX
UNITS NOTES
DC
ns
ns
ns
30
ns
ns
ns
50
ns
ns
ns
ns
ns
ns
ns
60
ns
6
ns
2
ms
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