Datasheet

LTC3858-1
6
38581fd
TYPICAL PERFORMANCE CHARACTERISTICS
Total Input Supply Current
vs Input Voltage
EXTV
CC
Switchover and INTV
CC
Voltages vs Temperature
INTV
CC
Line Regulation
Maximum Current Sense Voltage
vs I
TH
Voltage
SENSE
–
Pin Input Bias Current
Maximum Current Sense
Threshold vs Duty Cycle
Foldback Current Limit Quiescent Current vs Temperature
Shutdown Current vs Temperature
INPUT VOLTAGE (V)
5
SUPPLY CURRENT (µA)
350
20
3858 G10
200
100
10 15 25
50
0
400
300
250
150
30 35 40
300µA LOAD
FIGURE 12 CIRCUIT
V
OUT
= 3.3V
ONE CHANNEL ON
NO LOAD
TEMPERATURE (°C)
–45
EXTV
CC
AND INTV
CC
VOLTAGE (V)
5.4
30
3858 G11
4.8
4.4
–20 5 55
4.2
4.0
5.6
5.2
5.0
4.6
80 105 130
INTV
CC
EXTV
CC
RISING
EXTV
CC
FALLING
INPUT VOLTAGE (V)
0
5.0
INTV
CC
VOLTAGE (V)
5.1
5.1
5.2
5.2
5101520
3858 G12
25 30 35 40
V
SENSE
COMMON MODE VOLTAGE (V)
0
–600
SENSE
–
CURRENT (µA)
–500
–550
–450
–400
–300
–350
–200
–250
0
5
10 15 20
3858 G14
25
–50
–100
–150
FEEDBACK VOLTAGE (V)
0
0
MAXIMUM CURRENT SENSE VOLTAGE (mV)
10
30
40
50
0.6
90
3858 G16
20
0.3
0.1
0.7
0.4
0.2
0.8
0.5 0.9
60
70
80
I
TH
PIN VOLTAGE
0
CURRENT SENSE THRESHOLD (mV)
40
60
80
0.6 1.0
3858 G13
20
0
0.2 0.4
0.8 1.2 1.4
–20
–40
PULSE-SKIPPING MODE
FORCED CONTINUOUS MODE
Burst Mode OPERATION
(FALLING)
Burst Mode OPERATION
(RISING)
5% DUTY CYCLE
DUTY CYCLE (%)
0
MAXIMUM CURRENT SENSE VOLTAGE (mV)
40
60
80
3858 G15
20
0
20
40
50
100
80
60
10
30
90
70
TEMPERATURE (°C)
–45
110
QUIESCENT CURRENT (µA)
190
–20
30
55 130
3858 G17
230
210
150
130
170
5
80
105
PLLIN/MODE = 0
V
IN
= 12V
V
OUT
= 3.3V
ONE CHANNEL ON
TEMPERATURE (°C)
–45
SHUTDOWN CURRENT (µA)
8
9
10
30 80
3858 G18
7
6
–20 5
55 105 130
5
4