LTC3737 Datasheet, PDF (4/24 Pages) Linear Technology – Dual 2-Phase, No RSENSE DC/DC Controller with Output Tracking

LTC3737
TYPICAL PERFOR A CE CHARACTERISTICS
Efficiency vs Load Current
100
Burst Mode OPERATION
95 (SYNC/MODE = V_IN)
90
85
80
PULSE SKIPPING
75
(SYNC/MODE = 0V)
70
65
60
T_A = 25°C
V_IN = 3.3V
55
V_OUT = 2.5V
FIGURE 13 CIRCUIT
50
1
10
100
1000 10000
LOAD CURRENT (mA)
3737 G01
Efficiency vs Load Current
100
T_A = 25°C
95 V_OUT = 2.5V _{VIN = 3.3V}
90
85
V_IN = 4.2V
80
V_IN = 5V
75
70
65
60
55
50
1
10
100
1000
LOAD CURRENT (mA)
Load Step (Burst Mode Operation)
V_OUT
AC-COUPLED
100mV/DIV
I_L
2A/DIV
10000
3737 G02
V_IN = 3.3V
200µs/DIV
V_OUT = 1.8V
I_LOAD = 300mA TO 3A
SYNC/MODE = V_IN
FIGURE 13 CIRCUIT
3737 G03
Load Step (Pulse Skipping Mode)
V_OUT
AC-COUPLED
100mV/DIV
I_L
2A/DIV
Tracking Start-Up with Internal
Soft-Start (C_SS = 0nF)
V_OUT1
2.5V
V_OUT2
1.8V
500mV/
DIV
Tracking Start-Up with External
Soft-Start (C_SS = 10nF)
V_OUT1
2.5V
V_OUT2
1.8V
500mV/
DIV
V_IN = 3.3V
200µs/DIV
V_OUT = 1.8V
I_LOAD = 300mA TO 3A
SYNC/MODE = 0V
FIGURE 13 CIRCUIT
3737 G04
V_IN = 4.2V
250µs/DIV
R_LOAD1 = R_LOAD2 = 1Ω
FIGURE 13 CIRCUIT
3737 G05
V_IN = 4.2V
2.5ms/DIV
R_LOAD1 = R_LOAD2 = 1Ω
FIGURE 13 CIRCUIT
3737 G06
Regulated Feedback Voltage
vs Temperature
0.609
0.607
0.605
0.603
0.601
0.599
0.597
0.595
0.593
0.591
–60 –40 –20 0 20 40 60
TEMPERATURE (°C)
80 100
3737 G07
Maximum Current Sense Threshold
vs Temperature
135 _{IPRG = FLOAT}
130
125
120
115
–60 –40 –20 0 20 40 60
TEMPERATURE (°C)
80 100
3737 G08
Shutdown (RUN) Threshold
vs Temperature
1.0
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
–60 –40 –20 0 20 40 60 80 100
TEMPERATURE (°C)
3737 G09
3737f
4