Datasheet

3
LTC3405
3405fa
INPUT VOLTAGE (V)
2.5 3.0 4.0 5.0
EFFICIENCY (%)
4.5
95
90
85
80
75
70
65
60
55
50
3405 G02
3.5 5.5
Burst Mode OPERATION
V
OUT
= 1.8V
I
OUT
= 0.1mA
I
OUT
= 250mA
I
OUT
= 100mA
I
OUT
= 10mA
I
OUT
= 1mA
OUTPUT CURRENT (mA)
0.1
EFFICIENCY (%)
10
1000
100
90
80
70
60
50
40
30
20
10
0
3405 G03
1 100
V
IN
= 3.6V
V
IN
= 4.2V
V
IN
= 3.6V
V
IN
= 4.2V
V
OUT
= 1.8V
PULSE SKIPPING MODE
Burst Mode OPERATION
OUTPUT CURRENT (mA)
0.1
EFFICIENCY (%)
10
1000
100
90
80
70
60
50
40
3405 G04
1 100
V
IN
= 2.7V
V
IN
= 5.5V
V
IN
= 4.2V
V
IN
= 3.6V
V
OUT
= 1.8V
TYPICAL PERFOR A CE CHARACTERISTICS
UW
OUTPUT CURRENT (mA)
0.1
EFFICIENCY (%)
10
1000
100
90
80
70
60
50
40
3405 G05
1 100
V
IN
= 2.7V
V
IN
= 4.2V
V
OUT
= 1.3V
V
IN
= 3.6V
Efficiency vs Input Voltage
Efficiency vs Output Current
Efficiency vs Output Current
Efficiency vs Output Current
Reference Voltage vs
Temperature
Oscillator Frequency vs
Temperature
Oscillator Frequency vs
Supply Voltage
Output Voltage vs Load Current
R
DS(ON
) vs Input Voltage
TEMPERATURE (°C)
–50
REFERENCE VOLTAGE (V)
0.814
0.809
0.804
0.799
0.794
0.789
0.784
25 75
–25 0
50 100 125
V
IN
= 3.6V
3405 G06
TEMPERATURE (°C)
–50
FREQUENCY (MHz)
1.70
1.65
1.60
1.55
1.50
1.45
1.40
1.35
1.30
25 75
–25 0
50 100 125
V
IN
= 3.6V
3405 G07
SUPPLY VOLTAGE (V)
2
OSCILLATOR FREQUENCY (MHz)
1.8
1.7
1.6
1.5
1.4
1.3
1.2
34 56
3405 G08
LOAD CURRENT (mA)
0
OUTPUT VOLTAGE (V)
1.834
1.824
1.814
1.804
1.794
1.784
1.774
100
200 300 400
3405 G09
500 600
Burst Mode
OPERATION
PULSE SKIPPING MODE
V
IN
= 3.6V
INPUT VOLTAGE (V)
0
R
DS(0N)
(Ω)
2
4
5
3405 G10
13
6
7
1.2
1.1
1.0
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
MAIN SWITCH
SYNCHRONOUS
SWITCH
(From Figure1a Except for the Resistive Divider Resistor Values)