DS1685 Datasheet, PDF (29/33 Pages) Maxim Integrated Products – 3V/5V Real-Time Clocks

POWER-UP/DOWN TIMING—5V
(T_A = +25°C)
PARAMETER
SYMBOL
MIN
CS High to Power-Fail
t_PF
Recovery at Power-Up
t_REC
V_CC Slew Rate Power-Down
t_F
4.0 £ V_CC £ 4.5V
300
V_CC Slew Rate Power-Down
t_FB
3.0 £ V_CC £ 4.0V
10
V_CC Slew Rate Power-Up
t_R
4.5V ³ V_CC ³ 4.0V
0
Expected Data Retention
t_DR
10
DS1685/DS1687 3V/5V Real-Time Clocks
TYP MAX UNITS NOTES
0
ns
150
ms
ms
ms
ms
years
9, 10
POWER-UP/DOWN TIMING—3V
(T_A = +25°C)
PARAMETER
SYMBOL
MIN
CS High to Power-Fail
t_PF
Recovery at Power-Up
t_REC
V_CC Slew Rate Power-Down
t_F
2.5 £ V_CC £ 2.7V
300
V_CC Slew Rate Power-Up
t_R
2.7V ³ V_CC ³ 2.5V
0
Expected Data Retention
t_DR
10
TYP MAX UNITS NOTES
0
ns
150
ms
ms
ms
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
Input Capacitance on All Inputs
Except X1 and X2
Output Capacitance on IRQ,
SQW and DQ pins
SYMBOL
C_IN
C_OUT
MIN
TYP
MAX
UNITS NOTES
12
pF
12
pF
WAKE-UP/KICKSTART TIMING
(T_A = +25°C)
PARAMETER
SYMBOL
MIN
TYP
MAX
UNITS NOTES
Kickstart Input Pulse Width
t_KSPW
2
ms
Wake-Up/Kickstart Power On
Timeout
t_POTO
2
seconds
7
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