LTC3606B Datasheet, PDF (5/20 Pages) Linear Technology – 800mA Synchronous Step-Down DC/DC with Average Input Current Limit

LTC3606B
TYPICAL PERFORMANCE CHARACTERISTICS T_A = 25°C, V_IN = 5V, unless otherwise noted.
Efficiency vs Load Current
100
V_OUT = 1.2V
90
80
70
60
50
40
30
20
10
0
0.0001
V_IN = 2.7V
V_IN = 3.6V
V_IN = 4.2V
V_IN = 5V
0.001
0.01
0.1
OUTPUT CURRENT (A)
1
3606B G13
Load Regulation
3.0
2.5
2.0
1.5
1.0
0.5
0
–0.5
–1.0
0
V_OUT = 1.8V
V_OUT = 2.5V
V_OUT = 3.3V
100 200 300 400 500 600 700 800
LOAD CURRENT (mA)
3606B G15
Line Regulation
0.6
V_OUT = 1.8V
I_LOAD = 100mA
0.4
0.2
0
–0.2
–0.4
–0.6
2.5 3.0 3.5 4.0 4.5 5.0 5.5
V_IN (V)
3606B G16
Start-Up from Shutdown
RUN
2V/DIV
V_OUT
1V/DIV
I_L
250mA/DIV
200μs/DIV
V_IN = 5V, V_OUT = 3.3V
R_LOAD = 7Ω
C_LOAD = 4.7μF
Start-Up from Shutdown
RUN
2V/DIV
V_OUT
2V/DIV
R_LIM
1V/DIV
I_IN
500mA/DIV
3606B G17
2ms/DIV
V_IN = 5V, V_OUT = 3.4V
R_L = NO LOAD, C_L = 4.4mF
C_LIM = 2200pF, I_LIM = 500mA
3606B G18
V_RLIM vs Input Current
1.2
I_LIM = 475mA
R_LIM = 116k
1.0
0.8
0.6
0.4
0.2
0
0 100 200 300 400 500 600
I_IN (mA)
3606B G18b
Average Input Current Limit
vs Temperature
8
V_IN = 5V
6 ^{ILIM = 475mA}
4
Load Step
V_OUT
200mV/DIV
AC-COUPLED
2
I_L
0
1A/DIV
–2
I_LOAD
–4
1A/DIV
–6
–8
–50 –25
0 25 50 75
TEMPERATURE (°C)
100 125
3606B G19
20μs/DIV
V_IN = 5V, V_OUT = 3.3V
I_LOAD = 0A TO 800mA
C_OUT = 100μF, C_F = 20pF
Load Step
V_OUT
200mV/DIV
AC-COUPLED
3606B G20
I_L
1A/DIV
I_LOAD
1A/DIV
20μs/DIV
V_IN = 5V, V_OUT = 1.8V
I_LOAD = 80mA TO 800mA
C_OUT = 100μF, C_F = 20pF
3606B G21
3606bfa
5