LTC3619B_15 Datasheet, PDF (17/20 Pages) Linear Technology – 400mA/800mA Synchronous Step-Down DC/DC with Average Input Current Limit

Applications Information
LTC3619B
100
90
80
70
60
50
40
30
20
10
0
0.0001
10
V_IN = 2.7V
V_IN = 3.6V
V_IN = 4.2V
V_IN = 5V
1
0.1
0.01
0.001
0.01
V_OUT = 1.8V _0.001
0.1
1
OUTPUT CURRENT (A)
100
10
90 ^{VOUT = 3.4V}
80
1
70
60
50
0.1
40
30
20
10
0
0.0001
0.01
0.001
0.01
V_IN = 3.6V
V_IN = 4.2V
V_IN = 5V _0.001
0.1
1
OUTPUT CURRENT (A)
3619B F04b
Figure 4b. Efficiency vs Output Current
V_OUT
100mV/DIV
AC-COUPLED
I_L
500mA/DIV
I_LOAD
500mA/DIV
20µs/DIV
V_IN = 5V, V_OUT = 1.8V
I_LOAD = 40mA TO 400mA
C_L = 10µF
V_OUT
200mV/DIV
V_IN
1V/DIV
AC-COUPLED
I_OUT
500mA/DIV
I_IN
500mA/DIV
1ms/DIV
V_IN = 5V, 500mA COMPLIANT
R_LIM = 116kΩ, C_LIM = 2200pF
I_LOAD = 0A TO 2A, C_OUT = 4.4mF, V_OUT = 3.4V
I_LIM = 475mA, CHANNEL 1 NOT LOADED
3619B F04c
Figure 4c. Transient Response
3619bfb
17