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STK18TA8
April 2005
Document Control #ML0028 rev 0.8
5
RTC DC CHARACTERISTICS
Commercial
Industrial
Symbol
Parameter
MIN
MAX
MIN
MAX
Units
Notes
IBAK
RTC Backup Current
-
300
-
350
nA
From either VRTCcap or VRTCbat
VRTCbat
RTC Battery Pin Voltage
1.8
3.3
1.8
3.3
V
Typical = 3.0 Volts during normal
operation
VRTCcap
RTC Capacitor Pin Voltage
1.2
2.7
1.2
2.7
V
Typical = 2.4 Volts during normal
operation
-
1
-
1
min
@ MIN Temperature from Power up
or Enable
tOSCS
RTC Oscillator time to start
-
10
-
10
sec
@25ºC from Power up or Enable
RTC RECOMMENDED COMPONENT CONFIGURATION
X1
X2
Recommended Values
Y1 = 32.768 KHz
RF = 10M Ohm
C1 = 2.2 pF
C2 = 47 pF
Figure 4. RTC COMPONENT CONFIGURATION