LTC3604 Datasheet, PDF (4/24 Pages) Linear Technology – 2.5A, 15V Monolithic Synchronous Step-Down Regulator

LTC3604
ELECTRICAL CHARACTERISTICS
Note 3: T_J is calculated from the ambient temperature, T_A, and power
dissipation, P_D, according to the following formula:
T_J = T_A + (P_D • θ_JA)
where θ_JA = 45°C/W for the QFN package and θ_JA = 38°C/W for the MSOP
package.
Note 4: Maximum allowed current draw when used as a regulated output
is 5mA. This supply is only intended to provide additional DC load current
as needed and not intended to regulate large transient or ac behavior as
these waveforms may impact LTC3604 operation.
Note 5: This IC includes overtemperature protection that is intended
to protect the device during momentary overload conditions. Junction
temperature will exceed 125°C when overtemperature protection is active.
Continuous operation above the specified maximum operating junction
temperature may impair device reliability.
TYPICAL PERFORMANCE CHARACTERISTICS
T_A = 25°C, V_IN = 12V, f_O = 1MHz, L = 1.5μH unless otherwise noted.
Efficiency vs Load Current
Burst Mode Operation
100
V_OUT = 1.8V
90
80
70
60
50
40
30
20
10
0
0.001
V_IN = 4V
V_IN = 8V
V_IN = 12V
0.01
0.1
1
10
LOAD CURRENT (A)
3604 G01
Efficiency vs Input Voltage
Burst Mode Operation
100
95
90
85
80
75
70
I_LOAD = 500mA
I_LOAD = 100mA
65
I_LOAD = 10mA
I_LOAD = 2.5A
60
4
6
8 10 12 14 16
INPUT VOLTAGE (V)
3604 G04
Efficiency vs Load Current
Forced Continuous Mode
100
V_OUT = 1.8V
90
80
70
60
50
40
30
20
10
0
0.001
V_IN = 4V
V_IN = 8V
V_IN = 12V
0.01
0.1
1
10
LOAD CURRENT (A)
3604 G02
Efficiency vs Frequency
Forced Continuous Mode
94
V_OUT = 1.8V
I_LOAD = 800mA
92
90
L = 1.5μH
88
86
L = 0.68μH
84
82
0.5
1
1.5
2
2.5
3
FREQUENCY (MHz)
3604 G05
Efficiency vs Load Current
100
90
BURST
80
70
60
FORCED
CONTINUOUS
50
40
30
20
10
0
0.001
V_OUT = 3.3V
V_OUT = 5V
0.01
0.1
1
10
LOAD CURRENT (A)
3604 G03
Reference Voltage vs
Temperature
0.605
0.603
0.601
0.599
0.597
0.595
–50 –25
0 25 50 75
TEMPERATURE (°C)
100 125
3604 G06
3604f
4