Datasheet

LTC3859
10
3859fa
TYPICAL PERFORMANCE CHARACTERISTICS
Buck Foldback Current Limit
Oscillator Frequency
vs Temperature
Undervoltage Lockout Threshold
vs Temperature
Shutdown (RUN) Threshold
vs Temperature
Charge Pump Charging Current
vs Operating Frequency
Charge Pump Charging Current
vs Switch Voltage
Shutdown Current vs Temperature
Shutdown Current
vs Input Voltage Quiescent Current vs Temperature
TEMPERATURE (°C)
–45
SHUTDOWN CURRENT (µA)
22
20
16
14
10
18
12
8
30 55 80 105 130–20
3859 G28
5
INPUT VOLTAGE (V)
5
SHUTDOWN CURRENT (µA)
25
20
15
5
10
0
20 25 30 35 4010
3859 G29
15
TEMPERATURE (°C)
–45
QUIESCENT CURRENT (µA)
100
90
80
50
60
70
40
30 55 80 105 130
ONE CHANNEL ON
–20
3859 G30
ALL CHANNELS ON
5
FEEDBACK VOLTAGE (mV)
0
MAXIMUM CURRENT SENSE VOLTAGE (mV)
70
60
50
20
10
30
40
65
55
45
15
5
25
35
0
300 400 500 600 700 800100
3859 G31
200
TEMPERATURE (°C)
–45
FREQUENCY (kHz)
600
550
500
350
400
450
300
30 55 80 105 130–20
3859 G32
FREQ = INTV
CC
FREQ = GND
5
TEMPERATURE (°C)
–45
INTV
CC
VOLTAGE (V)
4.4
4.3
4.2
3.6
3.8
4.0
3.4
3.5
3.7
3.9
4.1
30 55 80 105 130–20
3859 G33
RISING
FALLING
5
TEMPERATURE (°C)
–45
RUN PIN VOLTAGE (V)
1.40
1.35
1.30
1.20
1.00
1.15
1.10
1.05
1.25
30 55 80 105 130–20
3859 G34
RUN1 RISING
RUN2,3 RISING
RUN1 FALLING
RUN2,3 FALLING
5
OPERATING FREQUENCY (kHz)
100
CHARGE PUMP CHARGING CURRENT (µA)
100
80
90
60
70
20
30
0
10
40
50
400 500 600 700 800200
3859 G35
–45°C
25°C
130°C
300
V
BOOST3
= 16V
V
SW3
= 12V
SWITCH VOLTAGE (V)
5
CHARGE PUMP CHARGING CURRENT (µA)
100
80
90
60
70
20
30
0
10
40
50
20 25 30 35 4010
3859 G36
FREQ = 0V
FREQ = INTV
CC
15
V
BOOST3
– V
SW3
= 4V