Datasheet

LTC3851-1
6
38511fa
TYPICAL PERFORMANCE CHARACTERISTICS
Maximum Current Sense Threshold
vs Common Mode Voltage
Maximum Peak Current Sense
Threshold vs I
TH
Voltage
Burst Mode Peak Current Sense
Threshold vs I
TH
Voltage
Maximum Current Sense
Threshold vs Duty Cycle
Regulated Feedback Voltage
vs Temperature
INTV
CC
Line Regulation
Shutdown (RUN) Threshold
vs Temperature
Maximum Current Sense
Threshold vs Feedback Voltage
(Current Foldback)
TK/SS Pull-Up Current
vs Temperature
INPUT VOLTAGE (V)
4812
3.5
INTV
CC
VOLTAGE (V)
3.7
4.1
4.3
4.5
28 32 36
5.3
38511 G13
3.9
16 20 24 40
4.7
4.9
5.1
I
LOAD
= 0mA
I
LOAD
= 25mA
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
38511 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
38511 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
38511 G16
2.40.60.4 1.0 1.4 1.8 2.2
BURST COMPARATOR FALLING THESHOLD:
V
ITH
= 0.4V
MAXIMUIM
MINIMUIM
FEEDBACK VOLTAGE (V)
0
MAXIMUM V
SENSE
(mV)
0.8
38511 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
TK/SS CURRENT (µA)
0.6
0.8
0.9
1.0
1.5
1.2
0
50
75
38511 G19
0.7
1.3
1.4
1.1
–25
25
100
125
TEMPERATURE (°C)
–50 –25
0.9
RUN PIN VOLTAGE (V)
1.1
1.4
0
50
75
38511 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
38511 G21
800
798
–25 0
50 100 125
796
794
DUTY CYCLE (%)
0
0
CURRENT SENSE THRESHOLD (mV)
10
30
40
50
40
80
100
90
38511 G17
20
20 60
60
70
80