LTC3851-1_15 Datasheet, PDF (6/28 Pages) Linear Technology – Synchronous Step-Down Switching Regulator Controller

LTC3851-1
TYPICAL PERFORMANCE CHARACTERISTICS
INTV_CC Line Regulation
5.3
5.1
I_LOAD = 0mA
4.9
I_LOAD = 25mA
4.7
4.5
4.3
4.1
3.9
3.7
3.5
4
8 12 16 20 24 28 32 36 40
INPUT VOLTAGE (V)
38511 G13
Burst Mode Peak Current Sense
Threshold vs I_TH Voltage
60
MAXIMUIM
50
40
30
20
MINIMUIM
10
BURST COMPARATOR FALLING THESHOLD:
0 ^{VITH = 0.4V}
0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4
V_ITH (V)
38511 G16
TK/SS Pull-Up Current
vs Temperature
1.5
1.4
1.3
1.2
1.1
1.0
0.9
0.8
0.7
0.6
0.5
–50 –25
0 25 50 75
TEMPERATURE (°C)
100 125
38511 G19
6
Maximum Current Sense Threshold
vs Common Mode Voltage
90
80
70
60
50
40
30
20
10
0
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5
V_SENSE COMMON MODE VOLTAGE (V)
38511 G14
Maximum Current Sense
Threshold vs Duty Cycle
90
80
70
60
50
40
30
20
10
0
0
20
40
60
80 100
DUTY CYCLE (%)
38511 G17
Shutdown (RUN) Threshold
vs Temperature
1.4
1.3
RUN RISING THRESHOLD (ON)
1.2
RUN FALLING THRESHOLD (OFF)
1.1
1.0
0.9
–50 –25
0 25 50 75
TEMPERATURE (°C)
100 125
38511 G20
Maximum Peak Current Sense
Threshold vs I_TH Voltage
90
DUTY CYCLE RANGE: 0% TO 100%
80
70
60
50
40
30
20
10
0
–10
–20
0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4
V_ITH (V)
38511 G15
Maximum Current Sense
Threshold vs Feedback Voltage
(Current Foldback)
90
80
70
60
50
40
30
20
10
0
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8
FEEDBACK VOLTAGE (V)
38511 G18
Regulated Feedback Voltage
vs Temperature
806
804
802
800
798
796
794
–50 –25
0 25 50 75
TEMPERATURE (°C)
100 125
38511 G21
38511fa