Datasheet

4
LTC1771
TYPICAL PERFOR A CE CHARACTERISTICS
UW
Load Regulation
Active Mode Quiescent Current
vs Input Voltage
Sleep Quiescent Current
vs Input Voltage
LOAD CURRENT (A)
0
–0.2
0
V
IN
= 15V
V
IN
= 5V
0.4
1.5
1771 G04
–0.4
–0.6
0.5 1.0 2.0
–0.8
–1.0
0.2
∆V
OUT
(%)
Burst Mode OPERATION
DISABLED
Burst Mode
OPERATION
ENABLED
FIGURE 1 CIRCUIT
INPUT VOLTAGE (V)
0
ACTIVE MODE QUIESCENT CURRENT (µA)
100
150
16
1771 G05
50
0
4
8
10
20
200
12
2
6
18
14
T
A
= –50°C
T
A
= 100°C
T
A
= 25°C
INPUT VOLTAGE (V)
0
SLEEP QUIESCENT CURRENT (µA)
4
8
12
2
6
10
4 8 12 16
1771 G06
2020 6 10 14 18
T
A
= –50°C
T
A
= 25°C
T
A
= 100°C
Shutdown Quiescent Current
vs Input Voltage
Run/SS Current vs Input Voltage
Current Sense Voltage
vs Temperature
INPUT VOLTAGE (V)
0
SHUTDOWN QUIESCENT CURRENT (µA)
4
6
16
1771 G07
2
0
4
8
10
20
8
12
2
6
18
14
T
A
= –50°C
T
A
= 100°C
T
A
= 25°C
INPUT VOLTAGE (V)
0
SOFT-START CURRENT (µA)
3
4
5
16
1771 G08
2
1
0
4
8
12
218
6
10
14
20
T
A
= –50°C
T
A
= 25°C
T
A
= 100°C
TEMPERATURE (°C)
–50
–50
CURRENT SENSE VOLTAGE (mV)
0
50
100
150
200
–25
02550
1771 G09
75 100
V
IN
= 10V
MAXIMUM
MINIMUM
BURST THRESHOLD
Reference Voltage
vs Temperature
TEMPERATURE (°C)
–50
1.21
REFERENCE VOLTAGE (V)
1.22
1.23
1.24
1.25
–25 0 25 50
1771 G10
75 100
V
IN
= 10V
Load Step Transient Response
V
OUT
100mV/DIV
INDUCTOR
CURRENT
1A/DIV
V
IN
= 10V 50µs/DIV 1771 G11
V
OUT
= 3.3V
I
LOAD
= 100mA TO 2A
FIGURE 1 CIRCUIT
Burst Mode Operation
V
OUT
50mV/DIV
INDUCTOR
CURRENT
0.5A/DIV
V
IN
= 10V 10µs/DIV 1771 G12
V
OUT
= 3.3V
I
LOAD
= 100mA
FIGURE 1 CIRCUIT