Datasheet

DS1685/DS1687 3V/5V Real-Time Clocks
29 of 34
POWER-UP/DOWN TIMING—5V
(T
A
= +25°C)
PARAMETER SYMBOL MIN TYP MAX UNITS NOTES
CS High to Power-Fail
t
PF
0 ns
Recovery at Power-Up t
REC
150 ms
V
CC
Slew Rate Power-Down
t
F
4.0
≤
V
CC
≤
4.5V
300
µs
V
CC
Slew Rate Power-Down
t
FB
3.0
≤
V
CC
≤
4.0V
10
µs
V
CC
Slew Rate Power-Up
t
R
4.5V
≥
V
CC
≥
4.0V
0
µs
Expected Data Retention t
DR
10 years 9, 10
POWER-UP/DOWN TIMING—3V
(T
A
= +25°C)
PARAMETER SYMBOL MIN TYP MAX UNITS NOTES
CS High to Power-Fail
t
PF
0 ns
Recovery at Power-Up t
REC
150 ms
V
CC
Slew Rate Power-Down
t
F
2.5
≤
V
CC
≤
2.7V
300
µs
V
CC
Slew Rate Power-Up
t
R
2.7V
≥
V
CC
≥
2.5V
0
µs
Expected Data Retention t
DR
10 years 9, 10
WARNING: Under no circumstances are negative undershoots, of any amplitude, allowed
when device is in battery-backup mode.
CAPACITANCE
(T
A
= +25°C)
PARAMETER SYMBOL MIN TYP MAX UNITS NOTES
Input Capacitance on All Inputs
Except X1 and X2
C
IN
12 pF
Output Capacitance on IRQ,
SQW and DQ pins
C
OUT
12 pF
WAKE-UP/KICKSTART TIMING
(T
A
= +25°C)
PARAMETER SYMBOL MIN TYP MAX UNITS NOTES
Kickstart Input Pulse Width t
KSPW
2
µs
Wake-Up/Kickstart Power On
Timeout
t
POTO
2 seconds 7