Datasheet

LTC3676/LTC3676-1
7
3676fa
For more information www.linear.com/LTC3676
TYPICAL PERFORMANCE CHARACTERISTICS
Standby I
VIN
vs V
IN
LDO2 to LDO4 I
VIN
vs V
IN
Step-Down Switching Regulator
I
VIN
vs V
IN
ELECTRICAL CHARACTERISTICS
Note 3: The LTC3676 includes overtemperature protection that is intended
to protect the device during momentary overload conditions. Junction
temperature will exceed 150°C when overtemperature protection is active.
Continuous operation above the specified maximum operating junction
temperature may impair device reliability.
Note 4: Dropout voltage is defined as (V
IN
– V
LDO1
) for LDO1 or
(V
IN_Lx
– V
LDOx
) for other LDOs when V
LDOx
is 3% lower than V
LDOx
measured with V
IN
= V
IN_Lx
= 4.3V.
VOLTAGE (V)
2.5
I
VIN
(µA)
8
3676 G01
4
0
3.5 4.5
3.0
4.0 5.0
12
16
6
2
10
14
5.5
VOLTAGE (V)
2.5
0
I
VIN
(µA)
100
300
400
500
4.5
900
3676 G03
200
3.5
3.0
5.0
4.0 5.5
600
700
800
PULSE-SKIPPING MODE
ENABLE FOUR BUCKS
ENABLE THREE BUCKS
ENABLE TWO BUCKS
ENABLE ONE BUCK
Note 5: Dynamic supply current is higher due to the gate charge being
delivered at the switching frequency.
Note 6: Soft-Start measured in test mode with regulator error amplifier in
unity-gain mode.
Note 7: The switching regulator PMOS and NMOS on-resistance is
guaranteed by correlation to wafer level measurements.
Step-Down Switching Regulator
I
VIN
vs V
IN
Input Supply Current
vs Temperature
Oscillator Frequency
vs Temperature
VOLTAGE (V)
2.5
0
I
VIN
(µA)
20
60
80
100
4.5
180
3676 G04
40
3.5
3.0
5.0
4.0 5.5
120
140
160
Burst Mode OPERATION
ENABLE FOUR BUCKS
ENABLE THREE BUCKS
ENABLE TWO BUCKS
ENABLE ONE BUCK
V
IN
= 3.8V, T
A
= 25°C unless otherwise noted
V
IN
(V)
2.50
V
IN
CURRENT (µA)
100
150
3676 G02
50
0
3.50
4.50
5.50
250
200
ENABLE 3 LDOs
ENABLE 2 LDOs
ENABLE 1 LDO
TEMPERATURE (°C)
–50
0
V
IN
CURRENT (µA)
200
400
600
800
1000
1200
0 50
PULSE-SKIPPING
STANDBY
Burst Mode OPERATION
100 150
3676 G05
ALL REGULATORS ENABLED
TEMPERATURE (°C)
–50
2.00
FREQUENCY (MHz)
2.05
2.10
2.15
2.20
2.25
2.30
0 50 100 150
3676 G06