LTC3890-3 Datasheet, PDF (6/40 Pages) Linear Technology – 60V Low IQ, Dual, 2-Phase Synchronous Step-Down DC/DC Controller

LTC3890-3
Typical Performance Characteristics
Total Input Supply Current
vs Input Voltage
300
V_OUT = 3.3V
FIGURE 13 CIRCUIT
250
200
300µA LOAD
150
100
NO LOAD
50
0
5 10 15 20 25 30 35 40 45 50 55 60 65
INPUT VOLTAGE (V)
38903 G10
Maximum Current Sense Voltage
vs I_TH Voltage
80
5% DUTY CYCLE
60
PULSE-SKIPPING MODE
40
Burst Mode
OPERATION
20
0
–20
FORCED CONTINUOUS MODE
–40
0 0.2 0.4 0.6 0.8 1.0
V_ITH (V)
1.2 1.4
38903 G13
Current Limit
vs Feedback Voltage
80
70
60
50
40
30
20
10
0
0 100 200 300 400 500 600 700 800
FEEDBACK VOLTAGE (MV)
38903 G16
6
EXTV_CC Switchover and INTV_CC
Voltages vs Temperature
6.0
5.8
5.6
5.4
5.2
INTV_CC
5.0
4.8
EXTV_CC RISING
4.6
EXTV_CC FALLING
4.4
4.2
4.0
–75 –50 –25 0 25 50 75 100 125 150
TEMPERATURE (°C)
38903 G11
SENSE^– Pin Input Bias Current
800
700
600
500
400
300
200
100
0
–100
0
5
10 15 20 25
V_SENSE COMMON MODE VOLTAGE (V)
38903 G14
Quiescent Current vs Temperature
80
V_IN = 12V
75
70
65
60
55
50
45
40
35
30
–75 –50 –25 0 25 50 75 100 125 150
TEMPERATURE (°C)
38903 G17
For more information www.linear.com/3890-3
INTV_CC Line Regulation
5.5
5.0
4.5
4.0
3.5
3.0
I_LOAD = 10mA
0 5 10 15 20 25 30 35 40 45 50 55 60 65
INPUT VOLTAGE (V)
38903 G12
Maximum Current Sense
Threshold vs Duty Cycle
90
85
80
75
70
65
60
0 10 20 30 40 50 60 70 80 90 100
DUTY CYCLE (%)
38903 G15
INTV_CC vs Load Current
5.50
V_IN = 12V
5.25
EXTV_CC = 0V
5.00
EXTV_CC = 8.5V
4.75
4.50
EXTV_CC = 5V
4.25
4.00
0
20
40
60
80 100
LOAD CURRENT (mA)
38903 G18
38903f