LTC3672B-1_15 Datasheet, PDF (3/12 Pages) Linear Technology – Monolithic Fixed-Output 400mA Buck Regulator with Dual

LTC3672B-1
ELECTRICAL CHARACTERISTICS The ● denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T_A = 25°C. V_IN = 3.6V, unless otherwise noted.
SYMBOL
PARAMETER
CONDITIONS
MIN TYP MAX UNITS
R_PD,BUCKOUT
BUCKOUT Pulldown Resistance in Shutdown
R_PD,SW
SW Pulldown Resistance in Shutdown
t_SS,BUCK
Soft-Start Time
LDO Regulator 1: V_IN1 = 1.8V Unless Otherwise Noted
V_LDO1
Regulated Output Voltage
Line Regulation
with Respect to V_IN
with Respect to V_IN1
Load Regulation
Available Output Current
V_ENALL = 0V
V_ENALL = 0V
LDO1 Output, I_LDO1 = 1mA
I_LDO1 = 1mA
V_IN = 3V to 5.5V, V_IN1 = 1.8V
V_IN = 3.6V, V_IN1 = 1.7V to 1.9V
I_LDO1 = 1mA to 150mA
10
kΩ
10
kΩ
0.2
ms
● 1.17
1.2
1.23
V
0.05
1
–0.05
150
mV/V
mV/V
mV/mA
mA
Short-Circuit Output Current
347
mA
V_DROP1
t_SS,LDO1
R_PD,LDO1
LDO Regulator 2
Dropout Voltage (Note 6)
Soft-Start Time
Output Pulldown Resistance in Shutdown
I_LDO1 = 150mA
484
570
mV
0.3
ms
10
kΩ
V_LDO2
Regulated Output Voltage
Line Regulation with Respect to V_IN
Load Regulation
Available Output Current
LDO2 Output, I_LDO2 = 1mA
I_LDO2 = 1mA, V_IN = 3V to 5.5V
I_LDO2 = 1mA to 150mA
● 2.73
2.8
2.87
V
1
mV/V
0.1
mV/mA
150
mA
Short-Circuit Output Current
453
mA
V_DROP2
t_SS,LDO2
R_PD,LDO2
Dropout Voltage (Note 6)
Soft-Start Time
Output Pulldown Resistance in Shutdown
I_LDO2 = 150mA
188
250
mV
0.1
ms
10
kΩ
Note 1: Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2: The LTC3672B-1 is guaranteed to meet performance specifications
from 0°C to 85°C. Specifications over the –40°C to 85°C operating
temperature range are assured by design, characterization and correlation
with statistical process controls.
Note 3: This IC includes overtemperature protection that is intended
to protect the device during momentary overload conditions. Junction
temperature will exceed 125°C when overtemperature protection is active.
Continuous operation above the specified maximum operating junction
temperature may impair device reliability.
Note 4: Dynamic supply current is higher due to the gate charge delivered
to the buck regulator’s internal MOSFET switches at the switching
frequency.
Note 5: The current limit features of this part are intended to protect the
IC from short term or intermittent fault conditions. Continuous operation
above the specified maximum specified pin current rating may result in
device degradation or failure.
Note 6: Dropout voltage is the minimum input to output voltage differential
needed to maintain regulation at a specified output current. When LDO1 is
in dropout, its output voltage will be equal to: V_IN1 – V_DROP1. When LDO2
is in dropout, its output voltage will be equal to: V_IN – V_DROP2.
3672B1f
3