Rainbow Electronics DS1511 - Manual (Page 8)

DS1501/DS1511 Y2KC Watchdog Real-Time Clocks
8 of 20
WAKEUP/KICKSTART TIMING
(T
A
= +25°C) (Figure 7)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
Kickstart-Input Pulse Width t
KSPW
2 ms
Wakeup/Kickstart Power-On Timeout t
POTO
(Note 10) 2 s
Note: Time intervals shown above are referenced in Wakeup/Kickstart.
Figure 7. Wakeup/Kickstart Timing Diagram
tKSPW
tPO T O
V C C
C O N D IT IO N :
V P F V B A T < V P F
V B A T
0V
V B A T
V P F
0V V C C
C O N D IT IO N :
V B A T V P F >
T D F /K S F
(IN T E R N A L)
V IL
V IH
H I-Z
____
IR Q
V IL
V IH
H I-Z
____
P W R
V IH
V IL
___
K S
1 2 3 4 5 IN T E R V A L S
Note 1: Limits at -40°C are not production tested and are guaranteed by design.
Note 2: RTC modules can be successfully processed through conventional wave-soldering techniques as long as temperature exposure to the
lithium energy source contained within does not exceed +85°C. Post-sold cleaning with water-washing techniques is acceptable,
provided that ultrasonic vibration is not used to prevent damage to the crystal.
Note 3: Voltage referenced to ground.
Note 4: Outputs are open.
Note 5: The
IRQ, PWR, and RST outputs are open drain.
Note 6: If V
PF
is less than V
BAT
and V
BAUX
, the device power is switched from V
CC
to the greater of V
BAT
or V
BAUX
when V
CC
drops below V
PF
. If V
PF
is greater than V
BAT
and V
BAUX
, the device power is switched from V
CC
to the greater of V
BAT
or V
BAUX
when V
CC
drops below the greater
of V
BAT
or V
BAUX
.
Note 7: V
BAT
or V
BAUX
current. Using a 32,768Hz crystal connected to X1 and X2.
Note 8: These parameters are sampled with a 5pF load and are not 100% tested.
Note 9: t
DR
is the amount of time that the internal battery can power the internal oscillator and internal registers of the DS1511.
Note 10: If the oscillator is not enabled, the startup time of the oscillator after V
CC1
is applied will be added to the wakeup/kickstart timeout.
Note 11: Typical values are at +25°C, nominal (active) supply, unless otherwise noted.