LTC3802_15 Datasheet, PDF (7/28 Pages) Linear Technology – Dual 550kHz Synchronous 2-Phase DC/DC Controller with Programmable Up/Down Tracking

TYPICAL PERFOR A CE CHARACTERISTICS
LTC3802
Switching Frequency vs V_PLLLPF
850
T_A = 25°C
V_CC = 5V
750
Continuous Mode Operation
V_OUT1
5V
AC 20mV/DIV
650
550
450
350
250
0
0.4 0.8 1.2 1.6
V_PLLLPF (V)
TG1
20V/DIV
V_OUT2
1V
AC 20mV/DIV
TG2
20V/DIV
2 2.4
V_IN = 30V
3802 G17
0.5µs/DIV
3802 G18
Maximum Duty Cycle
vs V_CC Supply Voltage
100
T_A = 25°C
95 ^{fSW = 550kHz}
90
V_CMPIN > 0.54V
85
80
V_CMPIN < 0.54V
75
70
65
0
3 3.5 4 4.5 5 5.5 6
V_CC SUPPLY VOLTAGE (V)
3802 G20
Maximum Duty Cycle
vs Switching Frequency
100
T_A = 25°C
95 ^{VCC = 5V}
90
85
V_CMPIN > 0.54V
80
75
V_CMPIN < 0.54V
70
65
60
330 390 450 510 570 630 690 750
SWITCHING FREQUENCY (kHz)
3802 G21
I_IMAX and I_RUN/SS
vs Temperature
12.0
V_CC = 5V
11.5
11.0
20
15
I_RUN/SS
SINK CURRENT
10
10.5
5
I_IMAX
10.0
0
9.5
–5
9.0
I_RUN/SS
–10
SOURCE CURRENT
8.5
–15
8.0
– 50 – 25
0 25 50 75
TEMPERATURE (°C)
–20
100 125
3802 G23
I_IMAX vs V_CC Supply Voltage
11.5
T_A = 25°C
10.9
10.3
9.7
9.1
8.5
3
3.5 4 4.5 5 5.5 6
V_CC SUPPLY VOLTAGE (V)
3802 G24
Maximum Duty Cycle
vs Temperature
100
V_CC = 5V
95 ^{fSW = 550kHz}
90
85
V_CMPIN > 0.54V
80
75
V_CMPIN < 0.54V
70
65
60
– 50 – 25
0 25 50 75
TEMPERATURE (°C)
100 125
3802 G19
Duty Cycle vs V_COMP
100
90
V_IN = 5V
80
V_IN = 12V
70
60
V_IN = 30V
V_IN = 20V
50
40
30
20
T_A = 25°C
10
V_CC = 5V
V_CMPIN = V_FB
0
0.8 1 1.2 1.4 1.6 1.8 2 2.2 2.4
V_COMP (V)
3802 G22
Driver Supply Current vs Load
80
T_A = 25°C
PV_CC = V_BOOST – V_SW = 5V
60
I_PVCC
40
I_BOOST1
20
I_BOOST2
0
0 2000 4000 6000 8000 10000
C_TG, C_BG LOAD (pF)
3802 G25
3802f
7