LTC3446EDE Datasheet, PDF (5/20 Pages) Linear Technology – Monolithic Buck Regulator with Dual VLDO Regulators

Typical Performance Characteristics
LTC3446
Undervoltage Lockout Threshold
vs Temperature
2.50
2.45
2.40
UVLO RISING
2.35
UVLO FALLING
2.30
2.25
2.20
2.15
2.10
2.05
2.00
–50 –30 –10 10 30 50 70 90 110 130
TEMPERATURE (°C)
3446 G04
Peak Inductor Current
vs I_TH Voltage
1.6
V_IN = 3.6V
1.4 ^VMODESEL ^{= 3.6V}
1.2
1.0
0.8
0.6
0.4
0.2
0
0 0.25 0.5 0.75 1 1.25 1.5 1.75 2
I_TH PIN VOLTAGE (V)
3446 G07
V_IN Bias Current
vs VLDO Load Current
450
400
350
300
250
200
150
100
50
0
0
V_IN = 3.6V
LV_IN = 1.5V
LV_OUT = 1.2V
ONLY ONE VLDO
ENABLED
–45°C
27°C
90°C
130°C
50 100 150 200 250 300
VLDO OUTPUT CURRENT (mA)
3446 G10
Maximum Peak Inductor Current
2.5
2.4
2.3
2.2
2.1
2.0
1.9
1.8
1.7
1.6
1.5
1.4
1.3
1.2
V_IN = 2.7V
V_IN = 3.6V
V_IN = 4.2V
1.1
V_IN = 5.5V
1.0
–50 –30 –10 10 30 50 70 90 110 130
TEMPERATURE (°C)
3446 G05
VLDO Current Limit
vs LV_IN Voltage
1800
V_IN = 3.6V
1600 LV_OUT = 0V
1400
1200
1000
800
PULSED MEASUREMENT,
600
T_J ≈ T_A ≈ 27°C
400
200
0
0.00
1.00 2.00 3.00 4.00 5.00 6.00
LV_IN PIN VOLTAGE (V)
3446 G08
LV_IN No-Load Operating Current
20
18
V_IN = 5V
BOTH VLDOS ON AND
16 ^{REGULATING 0.8V}
14
12
10
8
6
4
–45°C
27°C
2
90°C
130°C
0
0
1
2
3
4
5
6
LV_IN PIN VOLTAGE (V)
3446 G11
Oscillator Frequency
vs Temperature
2.50
2.45
2.40
2.35
2.30
2.25
2.20
2.15
2.10
V_IN = 2.7V
V_IN = 3.6V
2.05
V_IN = 4.2V
V_IN = 5.5V
2.00
–50 –30 –10 10 30 50 70 90 110 130
TEMPERATURE (°C)
3446 G06
VLDO Dropout Voltage
vs Load Current
100
V_IN = 2.8V
90 LV_OUT = 1.2V
80
–45°C
27°C
70
90°C
130°C
60
50
40
30
20
10
0
0 50 100 150 200 250 300
LOAD CURRENT (mA)
3446 G09
Enable/MODESEL Thresholds
1000
900
800
700
600
500
400
300
200
–45°C
27°C
100
90°C
130°C
0
2.5 3 3.5 4 4.5 5 5.5
V_IN (V)
3446 G12
3446ff
5