LTC3545-1_15 Datasheet, PDF (4/20 Pages) Linear Technology – Triple 800mA Synchronous Step-Down Regulator–2.25MHz

LTC3545/LTC3545-1
TYPICAL PERFORMANCE CHARACTERISTICS
V_REF vs Temperature at 2.25V,
3.6V, 5.5V
0.615
0.610
0.605
0.600
0.595
0.590
0.585
–50
0
50
100
TEMPERATURE (°C)
2.25V
3.6V
5.5V
150
3545 G01
Switching Frequency vs Supply
Voltage and Temperature
3.0
2.5
2.0
1.5
2
f_OSC = –40°C
f_OSC = 0°C
f_OSC = 25°C
f_OSC = 80°C
3
4
5
6
SUPPLY VOLTAGE (V)
3545 G02
Burst Mode Operation
SW
2V/DIV
V_OUT
20mV/DIV
I_L
100mA/DIV
V_IN = 3.6V
V_OUT = 1.8V
I_LOAD = 50mA
f_OSC = 2.25MHz
1μs/DIV
Efficiency vs Supply Voltage
100
V_OUT = 2V
T_A = 25°C
CHANNEL 3, ALL OTHERS OFF
95 ^fOSC ^{= 2.25MHz}
I_LOAD = 250mA
90
3545 G04
85
80
2
3
4
5
SUPPLY VOLTAGE (V)
6
3545 G05
Load Regulation, All Channels
1.2
T_A = 25°C
1.0
V_IN = 3.6V
UNTESTED CHANNELS OFF
0.8
PULSE SKIP MODE
CHANNEL 1
0.6
CHANNEL 2
CHANNEL 3
0.4
0.2
0
–0.2
–0.4
0
200
400
600
LOAD CURRENT (mA)
800
3545 G03
Supply Current vs Temperature
Burst Mode Operation
60
50
40
30
20
10 VFB3 = 0.625V
I_LOAD = 0mA
CHANNEL 3 ONLY
0
–50
0
50
V_IN = 5.5V
V_IN = 4.5V
V_IN = 3.5V
V_IN = 2.5V
100
150
TEMPERATURE (°C)
3545 G06
35451fb
4