Datasheet

LTC3852
6
3852f
TYPICAL PERFORMANCE CHARACTERISTICS
Controller Maximum Current
Sense Threshold
vs Common Mode Voltage
Controller Maximum Peak Current
Sense Threshold vs I
TH
Voltage
Controller Burst Mode Peak
Current Sense Threshold
vs I
TH
Voltage
Controller Maximum Current
Sense Threshold vs Duty Cycle
Controller Maximum Current
Sense Threshold vs Feedback
Voltage (Current Foldback)
Controller Input DC Supply
Current vs Input Voltage (V
IN2
)
Controller TRACK/SS Pull-Up
Current vs Temperature
INPUT VOLTAGE (V)
4
SUPPLY CURRENT (mA)
12
20
24 40
3852 G12
816
28
32
36
3.0
2.5
2.0
1.5
1.0
0.5
0
V
SENSE
COMMON MODE VOLTAGE (V)
0
0
V
SENSE
THRESHOLD (mV)
3 3.5 4 4.5
90
80
70
60
50
40
30
20
10
3852 G14
0.5 1 1.5 2 2.5 5
V
ITH
(V)
0 0.2 0.4 0.6
V
SENSE
(mV)
0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2
3852 G15
2.4
90
80
70
60
50
40
30
20
10
0
–10
–20
DUTY CYCLE RANGE: 0% TO 100%
V
ITH
(V)
V
SENSE
(mV)
60
50
40
30
20
10
0
0.8 1.2 1.6 2.0
3852 G16
2.40.60.4 1.0 1.4 1.8 2.2
BURST COMPARATOR FALLING THRESHOLD:
V
ITH
= 0.4V
MAXIMUM
MINIMUM
DUTY CYCLE (%)
0
0
CURRENT SENSE THRESHOLD (mV)
10
30
40
50
40
80
100
90
3852 G17
20
20 60
60
70
80
FEEDBACK VOLTAGE (V)
0
MAXIMUM V
SENSE
(mV)
0.8
3852 G18
0
0.2
0.4
0.6
0.1
0.3
0.5
0.7
90
80
70
60
50
40
30
20
10
TEMPERATURE (°C)
–50
0.5
TRACK/SS CURRENT (µA)
0.6
0.8
0.9
1.0
1.5
1.2
0
50
75
3852 G19
0.7
1.3
1.4
1.1
–25
25
100
125
Controller Shutdown (RUN)
Threshold vs Temperature
Controller Regulated Feedback
Voltage vs Temperature
TEMPERATURE (°C)
–50 –25
0.9
RUN PIN VOLTAGE (V)
1.1
1.4
0
50
75
3852 G20
1.0
1.3
1.2
25
100
125
RUN RISING THRESHOLD (ON)
RUN FALLING THRESHOLD (OFF)
TEMPERATURE (°C)
–50
REGULATED FEEDBACK VOLTAGE (mV)
802
804
806
25 75
3852 G21
800
798
–25 0
50 100 125
796
794