Datasheet

LTC3115-2
3
31152f
For more information www.linear.com/LTC3115-2
The l denotes the specifications which apply over the specified operating
junction temperature range, otherwise specifications are for T
A
= 25°C (Note 2). PV
IN
= V
IN
= 24V, PV
OUT
= 5V, unless otherwise noted.
elecTrical characTerisTics
PARAMETER CONDITIONS MIN TYP MAX UNITS
Input Operating Voltage
l
2.7 40 V
Output Operating Voltage
l
2.7 40 V
Input Undervoltage Lockout Threshold V
IN
Falling
V
IN
Rising
V
IN
Rising (0°C to 125°C)
l
l
2.4
2.6
2.7
2.8
2.725
V
V
V
Input Undervoltage Lockout Hysteresis 100 mV
V
CC
Undervoltage Lockout Threshold V
CC
Falling
l
2.4 2.6 V
V
CC
Undervoltage Lockout Hysteresis 200 mV
Input Current in Shutdown V
RUN
= 0V 3 10 µA
Input Quiescent Current in Burst Mode Operation V
FB
= 1.1V (Not Switching), V
PWM/SYNC
= Low 50 µA
Oscillator Frequency R
T
= 35.7k, V
PWM/SYNC
= High
l
900 1000 1100 kHz
Oscillator Operating Frequency V
PWM/SYNC
= High
l
100 2000 kHz
PWM/SYNC Clock Input Frequency
l
100 2000 kHz
PWM/SYNC Input Logic Threshold
l
0.5 1.0 1.5 V
Soft-Start Duration 9 ms
Feedback Voltage
l
977 1000 1017 mV
Feedback Voltage Line Regulation V
IN
= 2.7V to 40V 0.1 %
Feedback Pin Input Current 1 50 nA
RUN Pin Input Logic Threshold
l
0.3 0.8 1.1 V
RUN Pin Comparator Threshold V
RUN
Rising
l
1.16 1.21 1.26 V
RUN Pin Hysteresis Current 500 nA
RUN Pin Hysteresis Voltage 100 mV
Inductor Current Limit (Note 3)
l
2.4 3.0 3.7 A
Reverse Inductor Current Limit Current into PV
OUT
(Note 3) 1.5 A
Burst Mode Inductor Current Limit (Note 3) 0.65 1.0 1.35 A
Maximum Duty Cycle Percentage of Period SW2 is Low in Boost Mode,
R
T
= 35.7k (Note 5)
l
90 95 %
Minimum Duty Cycle Percentage of Period SW1 is High in Buck Mode,
R
T
= 35.7k (Note 5)
l
0 %
SW1, SW2 Minimum Low Time R
T
= 35.7k (Note 5) 100 ns
N-Channel Switch Resistance Switch A (From PV
IN
to SW1)
Switch B (From SW1 to PGND)
Switch C (From SW2 to PGND)
Switch D (From PV
OUT
to SW2)
150
150
150
150
mΩ
mΩ
mΩ
mΩ
N-Channel Switch Leakage PV
IN
= PV
OUT
= 40V 0.1 10 µA
PV
CC
/V
CC
External Forcing Voltage 4.58 5.5 V
V
CC
Regulation Voltage I
VCC
= 1mA 4.33 4.45 4.58 V
V
CC
Load Regulation I
VCC
= 1mA to 20mA 1.2 %
V
CC
Line Regulation I
VCC
= 1mA, V
IN
= 5V to 40V 0.5 %
V
CC
Current Limit V
CC
= 2.5V 50 110 mA
V
CC
Dropout Voltage I
VCC
= 5mA, V
IN
= 2.7V 50 mV
V
CC
Reverse Current V
CC
= 5V, V
IN
= 3.6V 10 µA
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 LTC3115-2 is tested under pulsed load conditions such
that T
J
≈ T
A
. The LTC3115E-2 is guaranteed to meet specifications from
0°C to 85°C junction temperature. Specifications over the –40°C to
125°C operating junction temperature range are ensured by design,
characterization and correlation with statistical process controls. The
LTC3115I-2 specifications are guaranteed over the –40°C to 125°C
operating junction temperature range. The LTC3115H-2 specifications are
guaranteed over the –40°C to 150°C operating junction temperature range.
The LTC3115MP-2 specifications are guaranteed over the –55°C to 150°C
operating junction temperature range. High junction temperatures degrade