LP3971
LDO RTC
Unless otherwise noted, V
IN
= 3.6V, C
IN
= 1.0 µF, C
OUT
= 0.47 µF, C
OUT
(V
RTC
) = 1.0 µF ceramic. Typical values and limits
appearing in normal type apply for T
J
= 25˚C. Limits appearing in
boldface
type apply over the entire junction temperature
range for operation, −40˚C to +125˚C. (Notes 2, 6, 7) and (Note 10)
Symbol
V
OUT
Accuracy
∆V
OUT
Parameter
Output Voltage Accuracy
Line Regulation
Load Regulation
Conditions
V
IN
Connected, Load Current =
1 mA
V
IN
= (V
OUT
nom + 1.0V) to 5.5V
From Main Battery
Load Current = 1 mA to 30 mA
From Backup Battery
V
IN
= 3.0V
Load Current = 1 mA to 10 mA
I
SC
Short Circuit Current Limit
From Main Battery
V
IN
= V
OUT
+0.3V to 5.5V
From Backup Battery
V
IN
-
V
OUT
I
Q
_Max
TP1
TP2
C
O
Dropout Voltage
Maximum Quiescent Current
RTC LDO Input Switched from
Main Battery to Backup Battery
RTC LDO Input Switched from
Backup Battery to Main Battery
Output Capacitor
Load Current = 10 mA
I
OUT
= 0 mA
V
IN
Falling
V
IN
Rising
Capacitance for Stability
ESR
0.7
5
30
2.9
3.0
1.0
500
100
mA
30
375
mV
µA
V
V
µF
mΩ
Min
2.632
Typ
2.8
Max
2.968
0.15
0.05
0.5
%/mA
Units
V
%/V
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