LTC3105
3
3105fb
For more information www.linear.com/LTC3105
ELECTRICAL CHARACTERISTICS
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 LTC3105 is tested under pulsed load conditions such that
T
J
≈
T
A
. The LTC3105E is guaranteed to meet specifications from
0°C to 85°C junction temperature. Specifications over the –40°C to 85°C
operating junction temperature range are assured by design, character-
ization and correlation with statistical process controls. Note that the
maximum ambient temperature consistent with these specifications is
determined by specific operating conditions in conjunction with board
layout, the rated package thermal impedance and other environmental
factors.
The l denotes the specifications which apply over the full operating
junction temperature range, otherwise specifications are at T
A
= 25°C (Note 2). V
AUX
= V
OUT
= 3.3V, V
LDO
= 2.2V, V
IN
= 0.6V, unless
otherwise noted.
PARAMETER CONDITIONS MIN TYP MAX UNITS
Step-Up Converter
Input Operating Voltage
l
0.225 5 V
Input Start-Up Voltage (Note 5)
T
J
= 0°C to 85°C (Note 5)
l
0.25 0.4
0.36
V
V
Output Voltage Adjust Range
l
1.6 5.25 V
Feedback Voltage (FB Pin)
l
0.984 1.004 1.024 V
V
OUT
I
Q
in Operation V
FB
= 1.10V 24 µA
V
OUT
I
Q
in Shutdown SHDN = 0V 10 µA
MPPC Pin Output Current V
MPPC
= 0.6V 9.72 10 10.28 µA
SHDN Input Logic High Voltage
l
1.1 V
SHDN Input Logic Low Voltage
l
0.3 V
N-Channel SW Pin Leakage Current V
IN
= V
SW
= 5V, V
SHDN
= 0V 1 10 µA
P-Channel SW Pin Leakage Current V
IN
= V
SW
= 0V, V
OUT
= V
AUX
= 5.25V 1 10 µA
N-Channel On-Resistance: SW to GND 0.5 Ω
P-Channel On-Resistance: SW to V
OUT
0.5 Ω
Peak Current Limit V
FB
= 0.90V, V
MPPC
= 0.4V (Note 3) 0.4 0.5 A
Valley Current Limit V
FB
= 0.90V, V
MPPC
= 0.4V (Note 3) 0.275 0.35 A
PGOOD Threshold (% of Feedback Voltage) V
OUT
Falling 85 90 95 %
LDO Regulator
LDO Output Adjust Range External Feedback Network, V
AUX
> V
LDO
l
1.4 5 V
LDO Output Voltage V
FBLDO
= 0V
l
2.148 2.2 2.236 V
Feedback Voltage (FBLDO Pin) External Feedback Network
l
0.984 1.004 1.024 V
Load Regulation I
LDO
= 1mA to 6mA 0.40 %
Line Regulation V
AUX
= 2.5V to 5V 0.15 %
Dropout Voltage I
LDO
= 6mA, V
OUT
= V
AUX
= 2.2V 105 mV
LDO Current Limit V
LDO
0.5V Below Regulation Voltage
l
6 12 mA
LDO Reverse-Blocking Leakage Current V
IN
= V
AUX
= V
OUT
= 0V, V
SHDN
= 0V 1 µA
Note 3: Current measurements are performed when the LTC3105 is not
switching. The current limit values measured in operation will be somewhat
higher due to the propagation delay of the comparators.
Note 4: This IC includes over temperature 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 5: The LTC3105 has been optimized for use with high impedance
power sources such as photovoltaic cells and thermoelectric generators.
The input start-up voltage is measured using an input voltage source with
a series resistance of approximately 200mΩ and MPPC enabled. Use of the
LTC3105 with lower resistance voltage sources or with MPPC disabled may
result in a higher input start-up voltage.
