Datasheet

LTC3642
5
3642fc
TYPICAL PERFORMANCE CHARACTERISTICS
Switch On-Resistance
vs Input Voltage
Switch On-Resistance
vs Temperature
Switch Leakage Current
vs Temperature
Efficiency vs Input Voltage
Run Comparator Threshold
Voltage vs Temperature
Internal Soft-Start Time
vs Temperature
Soft-Start Waveforms Operating Waveforms Load Step Transient Response
INPUT VOLTAGE (V)
0
0
SWITCH ON-RESISTANCE (Ω)
0.5
1.5
2.0
2.5
20
40
50
4.5
3642 G10
1.0
10 30
TOP
BOTTOM
3.0
3.5
4.0
TEMPERATURE (°C)
–40
SWITCH ON-RESISTANCE (Ω)
3
4
5
80
3642 G11
2
1
0
–10
20
50 110
BOTTOM
V
IN
= 10V
TOP
TEMPERATURE (°C)
0
SWITCH LEAKAGE CURRENT (µA)
0.2
0.4
0.6
0.1
0.3
0.5
–10 20 50 80
3642 G12
110–40
V
IN
= 45V
SW = 0V
SW = 45V
TEMPERATURE (°C)
–40
1.00
RUN COMPARATOR THRESHOLD (V)
1.05
1.10
1.15
1.20
1.30
–10
20 50 80
3642 G14
110
1.25
RISING
FALLING
TEMPERATURE (°C)
–40
0.90
INTERNAL SOFT-START TIME (ms)
0.95
1.00
1.05
1.10
1.20
–10
20 50 80
3642 G15
110
1.15
OUTPUT
VOLTAGE
1V/DIV
5ms/DIVC
SS
= 0.047µF
3642 G16
OUTPUT
VOLTAGE
50mV/DIV
SWITCH
VOLTAGE
5V/DIV
INDUCTOR
CURRENT
50mA/DIV
10µs/DIVV
IN
= 10V
I
SET
OPEN
I
LOAD
= 25mA
FIGURE 11 CIRCUIT
3642 G17
OUTPUT
VOLTAGE
25mV/DIV
LOAD
CURRENT
25mA/DIV
1ms/DIVV
IN
= 10V
I
SET
OPEN
FIGURE 11 CIRCUIT
3642 G18
INPUT VOLTAGE (V)
10
65
EFFICIENCY (%)
70
75
80
85
90
95
15 20 25 30 35 40
3642 G13
45
FIGURE 11 CIRCUIT
I
SET
OPEN
I
LOAD
= 50mA
I
LOAD
= 10mA
I
LOAD
= 1mA
T
A
= 25°C, unless otherwise noted.