LP3907 Datasheet, PDF (8/44 Pages) National Semiconductor (TI) – Dual High-Current Step-Down DC/DC and Dual Linear Regulator with I2C Compatible Interface

Low Drop Out Regulators, LDO1 and LDO2
Unless otherwise noted, V_IN = 3.6, C_IN = 1.0µF, C_OUT = 0.47µF. 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, 7, 8, 9, 10, 11, 12)
Symbol
Parameter
Conditions
Min
Typ
Max Units
V_IN
Operational Voltage Range
VINLDO1 and VINLDO2 PMOS
pins (Note 15)
1.74
5.5
V
V_OUT Accuracy Output Voltage Accuracy (Default V_OUT) Load current = 1 mA
−3
ΔV_OUT
Line Regulation
V_IN = (V_OUT + 0.3V) to 5.0V,
(Note 12), Load Current = mA
3
%
0.15 %/V
I_SC
V_IN – V_OUT
Load Regulation
Short Circuit Current Limit
Dropout Voltage
V_IN = 3.6V,
Load Current = 1mA to I_MAX
LDO1-2, V_OUT = 0V
Load Current = 50mA
(Note 10)
0.011 %/mA
500
mA
30
200
mV
PSRR
θn
Power Supply Ripple Rejection
Supply Output Noise
F = 10kHz, Load Current = I_MAX
10Hz < F < 100KHz
45
dB
80
µVrms
I_Q (Notes 11,
14)
Quiescent Current “On”
Quiescent Current “On”
Quiescent Current “Off”
I_OUT = 0mA
I_OUT = I_MAX
EN is de-asserted(Note 16)
40
µA
60
µA
0.03
µA
T_ON
C_OUT
Turn On Time
Output Capacitor
Start up from shut-down
Capacitance for stability
0°C ≤ T_J ≤ 125°C
−40°C ≤ T_J ≤ 125°C
ESR
300
µs
0.33
0.47
µF
0.68
1.0
µF
5
500
mΩ
Buck Converters SW1, SW2
Unless otherwise noted, V_IN = 3.6, 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 operation, −40°
C to +125°C. (Notes 2, 7, 8, 9, 11, 18)
Symbol
Parameter
Conditions
Min
Typ
Max Units
V_FB
V_OUT
Eff
Feedback Voltage
Line Regulation
Load Regulation
Efficiency
2.8< V_IN < 5.5
I_O =10mA
100mA < I_O < I_MAX
Load Current = 250mA
−3
+3
%
0.089
%/V
0.0013
96
%/mA
%
I_SHDN
f_OSC
I_PEAK
Shutdown Supply Current
Internal Oscillator Frequency
Buck1 Peak Switching Current Limit
Buck2 Peak Switching Current Limit
EN is de-asserted
0.01
1.7
2.1
1.5
1.0
µA
MHz
A
I_Q (Note 14) Quiescent Current “On”
No load PFM Mode
33
µA
R_DSON (P)
Pin-Pin Resistance PFET
200
mΩ
R_DSON (N)
Pin-Pin Resistance NFET
180
mΩ
T_ON
Turn On Time
Start up from shut-down
500
µs
C_IN
Input Capacitor
Capacitance for stability
10
µF
C_O
Output Capacitor
Capacitance for stability
10
µF
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