LTC3458_15 Datasheet, PDF (3/16 Pages) Linear Technology – 1.4A, 1.5MHz Synchronous Step-Up DC/DC Converter with Output Disconnect

LTC3458
ELECTRICAL CHARACTERISTICS The ● denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T_A = 25°C. V_IN = 3.3V, V_OUT = 5V, R_T = 200k, unless otherwise noted.
PARAMETER
CONDITIONS
MIN TYP MAX UNITS
Error Amplifier Sink Current
7
μA
SYNC Input High
● 1.5
V
SYNC Input Low
●
0.35
V
SHDN Input High
● 1.25
V
SHDN Input Low
●
0.3
V
BURST Mode Peak Current
BURST Threshold Voltage
R_ILIM = 124k
0.4
A
1.10
V
Note 1: Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2: 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.
Note 3: The LTC3458 is guaranteed to meet performance specifications
from 0°C to 70°C. Specifications over the –40°C to 85°C operating
temperature range are assured by design, characterization and correlation
with statistical process controls.
TYPICAL PERFOR A CE CHARACTERISTICS (T_A = 25°C unless otherwise specified)
I_LIMIT, I_BURST, T_ZERO Currents
Current Limit Accuracy
Burst Mode Quiescent Current
2000
1800
1600
I_LIMIT
1400
1200
1000
800
V_OUT = 7V
L = 10μH
R_ILIM = 124k
600 _{IBURST PEAK}
400
200
I_ZERO
0
–200
2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5
V_IN (V)
3458 G01
Typical Burst Mode Threshold and
Hysteresis vs R_BURST
160
140
120
OUT OF
100
BURST
80 _INTO
60 ^BURST
40
20
0
50 100 150 200 250 300
R_BURST (kΩ)
3458 G04
1.8
R_ILIMIT = 124k
1,7
1.6
1.5
1.4
–45 –30 –15 0 15 30 45 60 75 90
TEMPERATURE (°C)
3458 G02
Maximum Load Current in Burst
250
R_ILIM = 124k
200
3.3V_OUT
5V_OUT
7.5V_OUT
150
100
50
0
1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5
V_IN (V)
3458 G05
20
V_IN = 3.3V
V_OUT = 5V
15
I_VIN
10
5
I_VOUT
0
–40 –15 10
35
60
85
TEMPERATURE (°C)
3458 G03
Oscillator Programming Resistor
600
550
500
450
400
350
300
250
200
150
100
400
600 800 1000 1200 1400
OSCILLATOR FREQUENCY (kHz)
3458 G06
3458fa
3