Datasheet

LTC3865/LTC3865-1
7
3865fb
TYPICAL PERFORMANCE CHARACTERISTICS
Current Sense Threshold
vs I
TH
Voltage
Maximum Current Sense
Threshold vs Common Mode
Voltage
Maximum Current Sense
Threshold vs Duty Cycle
TK/SS Pull-Up Current
vs Temperature
Tracking Up and Down with
External Ramp
(Forced Continuous Mode)
Quiescent Current vs Input
Voltage without EXTV
CC
INTV
CC
Line Regulation
Maximum Current Sense
Voltage vs Feedback Voltage
(Current Foldback)
V
ITH
(V)
0
–40
V
SENSE
(mV)
–20
0
20
40
60
80
0.5 1 1.5 2
3865 G10
I
LIM
= INTV
CC
I
LIM
= GND
I
LIM
= FLOAT
V
SENSE
COMMON MODE VOLTAGE (V)
0
CURRENT SENSE THRESHOLD (mV)
30
40
50
3
5
20
10
0
12 4
60
70
80
3865 G11
I
LIM
= INTV
CC
I
LIM
= GND
I
LIM
= FLOAT
60
80
100
40
20
50
70
90
30
10
0
DUTY CYCLE (%)
0
CURRENT SENSE THRESHOLD (mV)
60
100
20 40 80
3865 G12
I
LIM
= INTV
CC
I
LIM
= GND
I
LIM
= FLOAT
TK/SS1
TK/SS2
2V/DIV
V
OUT1
= 1.5V
1 LOAD
500mV/DIV
V
OUT2
= 1.2V
1 LOAD
500mV/DIV
20ms/DIV
3865 G07
INPUT VOLTAGE (V)
0
INTV
CC
VOLTAGE (V)
4.25
4.50
4.75
40
3865 G09
4.00
3.50
3.75
3.00
10
20
30
5
15
25
35
3.25
5.25
5.00
FEEDBACK VOLTAGE (V)
0
0
MAXIMUM CURRENT SENSE VOLTAGE (mV)
20
40
60
0.1
0.2
0.3 0.4
3865 G13
0.5
80
100
10
30
50
70
90
0.6
I
LIM
= INTV
CC
I
LIM
= FLOAT
I
LIM
= GND
TEMPERATURE (°C)
–50
TK/SS CURRENT (µA)
1.75
25
3865 G14
1.00
0.50
–25 0 50
0.25
0
2.00
1.50
1.25
0.75
75 100 125
INPUT VOLTAGE (V)
510
0
QUIESCENT CURRENT (mA)
2
5
15
25
30
3865 G08
1
4
3
20
35
40