LTC3109_15 Datasheet, PDF (4/24 Pages) Linear Technology – Auto-Polarity, Ultralow Voltage Step-Up Converter and Power Manager

LTC3109
Electrical Characteristics
board layout, the rated thermal package thermal resistance and other
environmental factors. The junction temperature (T_J) is calculated from
the ambient temperature (T_A) and power dissipation (P_D) according to
the formula: T_J = T_A + (P_D • θ_JA°C/W), where θ_JA is the package thermal
impedance.
Note 3: Specification is guaranteed by design and not 100% tested in
production.
Note 4: Current measurements are made when the output is not switching.
Note 5: Failure to solder the exposed backside of the QFN package to the
PC board ground plane will result in a thermal resistance much higher
than 37°C/W.
Note 6: The Absolute Maximum Rating is a DC rating. Under certain
conditions in the applications shown, the peak AC voltage on the C2A and
C2B pins may exceed ±8V. This behavior is normal and acceptable because
the current into the pin is limited by the impedance of the coupling
capacitor.
Typical Performance Characteristics T_A = 25°C, unless otherwise noted.
I_IN vs V_IN
1000
V_OUT = 0V
100
I_VOUT vs V_IN
10000
1:100 RATIO, C1 = 1nF
1:50 RATIO, C1 = 4.7nF
1:20 RATIO, C1 = 10nF
V_OUT = 3.3V
1000 ^{NO LOAD ON VLDO}
10
1
10
1:100 RATIO, C1 = 1nF
1:50 RATIO, C1 = 4.7nF
1:20 RATIO, C1 = 10nF
100
V_IN (mV)
1000
3109 G01
100
10
10
100
V_IN (mV)
Input Resistance vs V_IN
7.0
V_OUT = 0V
6.5
6.0
5.5
5.0
4.5
4.0
3.5
3.0
2.5
2.0
10
1:100 RATIO, C1 = 1nF
1:50 RATIO, C1 = 4.7nF
1:20 RATIO, C1 = 10nF
100
V_IN (mV)
1000
3109 G03
Efficiency vs V_IN
50
1:100 RATIO, C1 = 1nF
45
1:50 RATIO, C1 = 4.7nF
40
1:20 RATIO, C1 = 10nF
V_OUT = 0V
35
30
25
20
15
10
5
0
10
100
V_IN (mV)
P_VOUT vs V_IN
100
1:50 RATIO
C1 = 4.7nF
10
1
V_OUT = 5V
V_OUT = 3.3V
1000
3109 G02
1000
3109 G04
0.1
10
100
V_IN (mV)
1000
3109 G18
Open-Circuit Start-Up Voltage
vs Source Resistance
90
80
70
60
50
40
30
20
10
0
0 1 2 3 4 5 6 7 8 9 10
SOURCE RESISTANCE (Ω)
3109 G05
3109fb
4
For more information www.linear.com/LTC3109