Datasheet

4
LTC1149
LTC1149-3.3/LTC1149-5
CCHARA TERIST
ICS
UW
AT
Y
P
I
CA
LPER
F
O
R
C
E
Load Regulation
Efficiency vs Input Voltage
Line Regulation
Operating Frequency
vs (V
IN
– V
OUT
)
Gate Charge Supply Current Current Sense Threshold Voltage
DC Supply Current
Supply Current in Shutdown
Off-Time vs V
OUT
LOAD CURRENT (A)
0
–100
∆V
OUT
(mV)
–80
–60
–40
–20
0
20
0.5 1.0 1.5 2.0
1149 G03
2.5
FIGURE 1 CIRCUIT
V
IN
= 24V
OPERATING FREQUENCY (kHz)
50
0
GATE CHARGE CURRENT (mA)
5
10
15
20
25
30
100 150 200 250
1149 G07
Q
P
+ Q
N
= 100nC
Q
P
+ Q
N
= 50nC
OUTPUT VOLTAGE (V)
1
OFF-TIME (µs)
40
50
60
5
1149 G08
30
20
0
2
34
10
80
70
0
LTC1149-5
LTC1149-3.3
TEMPERATURE (°C)
20
SENSE VOLTAGE (mV)
80
100
120
100
1149 G09
60
40
0
40
60 80
20
160
140
0
MAXIMUM
THRESHOLD
MINIMUM
THRESHOLD
(V
IN
– V
OUT
) VOLTAGE (V)
0
NORMALIZED FREQUENCY
1.0
1.5
20
1149 G06
0.5
0
5
10
15
25
2.0
V
OUT
= 5V
T = 70°C
T = 0°C
T = 25°C
INPUT VOLTAGE (V)
0
SUPPLY CURRENT (µA)
200
300
40
1149 G05
100
0
10
20
30
50
400
V
SD2
= 2V
INPUT VOLTAGE (V)
0
0
SUPPLY CURRENT (mA)
0.5
1.0
1.5
2.0
2.5
3.0
10 20 30 40
1149 G04
50
ACTIVE MODE
SLEEP MODE
INPUT VOLTAGE (V)
0
–60
∆V
OUT
(mV)
–40
–20
0
20
40
60
10 20 30 40
1149 G02
50
FIGURE 1 CIRCUIT
I
LOAD
= 1A
INPUT VOLTAGE (V)
0
EFFICIENCY (%)
90
95
40
1149 G01
85
80
10
20
30
50
100
FIGURE 1 CIRCUIT
I
LOAD
= 1A