Datasheet

5
LTC1775
DUTY CYCLE
0
350
300
250
200
150
100
50
0
0.6
1775 • G10
0.2 0.4 0.8 1.0
MAXIMUM CURRENT SENSE VOLTAGE (mV)
TEMPERATURE (°C)
–40
MAXIMUM CURRENT SENSE VOLTAGE (mV)
320
310
300
290
280
35 85
1775 • G11
–15 10
60 110 135
TEMPERATURE (°C)
–40
FREQUENCY (kHz)
300
250
200
150
100
50
0
35 85
1775 • G12
–15 10
60 110 135
SYNC = 1.5V
SYNC = 0V
Maximum Current Sense Voltage
vs Duty Cycle
Maximum Current Sense Voltage
vs Temperature
Oscillator Frequency
vs Temperature
1530 G15
V
OUT
50mV
/DIV
I
TH
100mV
/DIV
I
L
2A/DIV
V
IN
= 20V
V
OUT
= 5V
I
LOAD
= 100mA
FIGURE 1 CIRCUIT
20µs/DIV
FCB Pin Current vs Temperature
RUN/SS Pin Current vs
Temperature
Burst Mode Operation
TEMPERATURE (°C)
–40
FCB CURRENT (µA)
35 85
1775 • G13
–15 10
60 110 135
0
–0.5
–1.0
–1.5
–2.0
TEMPERATURE (°C)
–40
RUN/SS CURRENT (µA)
0
–1
–2
–3
–4
–5
35 85
1775 • G14
–15 10
60 110 135
Soft Start
1530 G16
RUN/SS
5V/DIV
V
OUT
5V/DIV
I
L
5A/DIV
V
IN
= 20V
V
OUT
= 5V
R
LOAD
= 0.5Ω
FIGURE 1 CIRCUIT
20ms/DIV
1530 G17
V
OUT
100mV
/DIV
I
L
5A/DIV
V
IN
= 20V
V
OUT
= 5V
I
LOAD
= 100mA TO 2A
FIGURE 1 CIRCUIT
200µs/DIV
1530 G18
V
OUT
100mV
/DIV
I
L
5A/DIV
V
IN
= 20V
V
OUT
= 5V
I
LOAD
= 2A TO 8A
FIGURE 1 CIRCUIT
100µs/DIV
Transient Response
(Burst Mode Operation)Transient Response
TYPICAL PERFOR A CE CHARACTERISTICS
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