Datasheet

DS1390–DS1394
Low-Voltage SPI/3-Wire RTCs with
Trickle Charger
8
Maxim Integrated
OUTPUTS
V
CC
V
PF(MAX)
INPUTS
HIGH IMPEDANCE
RST
DON'T CARE
VALID
RECOGNIZED
RECOGNIZED
VALID
V
PF(MIN)
t
RST
t
RPU
t
R
t
F
V
PF
V
PF
Figure 5. Power-Up/Down Timing
t
RST
PB
DB
RST
Figure 6. Pushbutton Reset Timing
POWER-UP/POWER-DOWN CHARACTERISTICS
(T
A
= -40°C to +85°C) (Figures 5, 6)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
V
CC
Detect to Recognize Inputs
(V
CC
Rising)
t
RST
(Note 17) 160 200 ms
V
CC
Fall Time; V
PF(MAX)
to
V
PF(MIN)
t
F
300 µs
V
CC
Rise Time; V
PF(MIN)
to
V
PF(MAX)
t
R
0µs