LTC3851A-1_15 Datasheet, PDF (6/30 Pages) Linear Technology – Synchronous Step-Down Switching Regulator Controller

LTC3851A-1
Typical Performance Characteristics
Load Step
(Pulse-Skipping Mode)
I_LOAD
5A/DIV
0.2A TO 7.5A
I_L
5A/DIV
V_OUT
100mV/DIV
AC-COUPLED
V_OUT = 1.5V
100µs/DIV
V_IN = 12V
FIGURE 11 CIRCUIT
3851A1 G07
Inductor Current at Light Load
FORCED
CONTINOUS
MODE
5A/DIV
Burst Mode
OPERATION
5A/DIV
PULSE SKIP
MODE
5A/DIV
V_OUT = 1.5V
1µs/DIV
V_IN = 12V
I_LOAD = 1mA
FIGURE 11 CIRCUIT
3851A1 G08
Start-Up with Prebiased Output
at 2V
V_OUT
2V/DIV
V_FB
0.5V/DIV
TK/SS
0.5V/DIV
20ms/DIV
3851A1 G09
Coincident Tracking with Master
Supply
V_MASTER
0.5V/DIV
V_OUT
2A LOAD
0.5V/DIV
10ms/DIV
3851A1 G10
Ratiometric Tracking with Master
Supply
V_MASTER
0.5V/DIV
V_OUT
2A LOAD
0.5V/DIV
10ms/DIV
3851A1 G11
6
Input DC Supply Current
vs Input Voltage
3.0
2.5
2.0
1.5
1.0
0.5
0
4 8 12 16 20 24 28 32 36 40
INPUT VOLTAGE (V)
3851A1 G12
3851a1fa