LTC3440_15 Datasheet, PDF (3/20 Pages) Linear Technology – Micropower Synchronous Buck-Boost DC/DC Converter

LTC3440
ELECTRICAL CHARACTERISTICS The ● denotes specifications that apply over the full operating temperature
range, otherwise specifications are at T_A = 25°C. V_IN = V_OUT = 3.6V, R_T = 60k, unless otherwise noted.
PARAMETER
CONDITIONS
MIN
TYP
MAX UNITS
PMOS Switch Leakage
Switches A and D
0.1
10
µA
NMOS Switch On Resistance
Switches B and C
0.19
Ω
PMOS Switch On Resistance
Switches A and D
0.22
Ω
Input Current Limit
l
1
A
Maximum Duty Cycle
Boost (% Switch C On)
Buck (% Switch A On)
l 55
75
%
l 100
%
Minimum Duty Cycle
l
0
%
Frequency Accuracy
l 0.8
1
1.2
MHz
MODE/SYNC Threshold
0.4
2
V
MODE/SYNC Input Current
Error Amp AVOL
V_MODE/SYNC = 5.5V
0.01
1
µA
90
dB
Error Amp Source Current
15
µA
Error Amp Sink Current
380
µA
SHDN/SS Threshold
When IC is Enabled
l 0.4
1
1.5
V
When EA is at Maximum Boost Duty Cycle
2.2
V
SHDN/SS Input Current
V_SHDN = 5.5V
0.01
1
µA
Note 1: Absolute Maximum Ratings are those values beyond which the
life of the device may be impaired.
Note 2: The LTC3440E is guaranteed to meet performance specifications
from 0°C to 70°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: Current measurements are performed when the outputs are not
switching.
TYPICAL PERFORMANCE CHARACTERISTICS
Li-Ion to 3.3V Efficiency
(f_OSC = 300kHz)
100
90 _{Burst Mode}
OPERATION
80
70
V_IN = 4.2V
V_IN = 2.5V
60
V_IN = 3.3V
50
40
30
f_OSC = 300kHz
20
0.1
1
10
100
OUTPUT CURRENT (mA)
1000
3440 G01
Li-Ion to 3.3V Efficiency,
Power Loss (f_OSC = 1MHz)
100
1000
90 Burst Mode
OPERATION
80
100
V_IN = 4.2V
70
V_IN = 2.5V
V_IN = 3.3V
60
10
50
V_IN = 3.3V
40
1
30
20
0.1
f_OSC = 1MHz
0.1
1
10
100
1000
OUTPUT CURRENT (mA)
3440 G02
Li-Ion to 3.3V Efficiency
(f_OSC = 2MHz)
100
90 Burst Mode
OPERATION
80
70
60
V_IN = 2.5V
50
V_IN = 4.2V
V_IN = 3.3V
40
30
20
0.1
f_OSC = 2MHz
1
10
100
1000
OUTPUT CURRENT (mA)
3440 G03
For more information www.linear.com/LTC3440
3440fc
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