LTC3445_15 Datasheet, PDF (6/24 Pages) Linear Technology – I2C Controllable Buck Regulator with Two LDOs

LTC3445
TYPICAL PERFOR A CE CHARACTERISTICS
Slew Rates DAC Min to DAC Max
Buck (DAC = Min)
100mA to 300mA Load Step
Buck (DAC = Max)
100mA to 400mA Load Step
200mV/DIV
100µs/DIV
BUCK
VOLTAGE
50mV/DIV
LOAD
CURRENT
100mA/DIV
3445 G13
20µs/DIV
BUCK
VOLTAGE
50mV/DIV
LOAD
CURRENT
100mA/DIV
3445 G14
20µs/DIV
3445 G15
Buck Switching Frequency
vs V_CC1
1.60
1.56
1.52
1.48
1.44
1.40
2.5
3.5
4.5
V_CC1 (V)
5.5
3445 G16
V_CC BATT vs V_CC1
6 _{VTRACK = VBACKUP = 2V}
5
4
V_CC BATT
3
2
V_CC1
1
0
0
V_CC1 RAMP (V)
3445 G19
Buck Switching Frequency
vs Temperature
1.560
Soft-Start (DAC = Min and Max)
4.7Ω Load
1.540
1.520
BUCK
OUTPUTS
500mV/DIV
1.500
1.480
1.460
200µs/DIV
3445 G18
1.440
–50 –25 0 25 50 75 100 125 150
TEMPERATURE (°C)
3445 G17
V_CC BATT vs V_TRACK
6 _{VCC1 = 5.5V}
V_BACKUP = 2V
5
4
V_CC BATT
0mA
5mA
PowerPath LDO Load Step
1mA to 5.5mA
V_CC BATT
20mV/DIV
3
2
V_TRACK
1
0
0
V_TRACK RAMP (V)
LOAD
CURRENT
10mA/DIV
3445 G20
200µs/DIV
3445 G21
3445fa
6