LP3971
LDO 1 to 5
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, 10, 11, 15) and (Note 16).
Symbol
V
OUT
Accuracy
∆V
OUT
Parameter
Output Voltage Accuracy (Default
V
OUT
)
Line Regulation
Load Regulation
I
SC
V
IN
-
V
OUT
PSRR
I
Q
Short Circuit Current Limit
Dropout Voltage
Power Supply Ripple Rejection
Quiescent Current “On”
Quiescent Current “On”
Quiescent Current “Off”
T
ON
C
OUT
Turn On Time
Output Capacitor
Conditions
Load Current = 1 mA
V
IN
=3.1v to 5.0V, (Note 11) Load
Current = 1 mA
V
IN
= 3.6V,
Load Current = 1 mA to I
MAX
LDO1–4, V
OUT
= 0V
LDO5, V
OUT
= 0V
Load Current = 50 mA (Note 7)
f = 10 kHz, Load Current = I
MAX
I
OUT
= 0 mA
I
OUT
= I
MAX
EN is de-asserted
Start up from Shut-down
Capacitance for Stability
0˚C
≤
T
J
≤
125˚C
−40˚C
≤
T
J
≤
125˚C
ESR
0.33
0.68
5
45
40
60
0.03
300
0.47
µF
1.0
500
MΩ
µsec
µA
400
500
150
Min
−3
Typ
Max
3
0.15
0.011
Units
%
%/V
%/mA
mA
mV
dB
Buck Converters SW1, SW2, SW3
Unless otherwise noted, V
IN
= 3.6V, C
IN
= 10 µF, C
OUT
= 10 µF, L
OUT
= 2.2 µH 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 opera-
tion, −40˚C to +125˚C. (Notes 2, 6, 12) and (Note 13).
Symbol
V
OUT
Eff
I
SHDN
Efficiency
Shutdown Supply Current
Sync Mode Clock Frequency
f
OSC
I
PEAK
I
Q
R
DSON
(P)
R
DSON
(N)
T
ON
C
IN
C
O
Internal Oscillator Frequency
Peak Switching Current Limit
Quiescent Current “On”
Pin-Pin Resistance PFET
Pin-Pin Resistance NFET
Turn On Time
Input Capacitor
Output Capacitor
Start up from Shut-down
Capacitance for Stability
Capacitance for Stability
8
8
No Load PFM Mode
No Load PWM Mode
Parameter
Output Voltage Accuracy
Conditions
Default V
OUT
Load Current = 500 mA
EN is de-asserted
Synchronized from 13 MHz System
Clock
10.4
Min
−3
90
0.1
13
2.0
2.1
21
200
240
150
500
2.4
15.6
Typ
Max
+3
Units
%
%
µA
MHz
MHz
A
µA
mΩ
mΩ
µsec
µF
µF
9
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