LTC3458 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
SHDN Input High
SHDN Input Low
BURST Mode Peak Current
BURST Threshold Voltage
CONDITIONS
R_ILIM = 124k
MIN TYP MAX UNITS
● 1.25
V
●
0.3
V
0.4
A
1.10
V
Note 1: Absolute Maximum Ratings are those values beyond which the life
of a device may be impaired.
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
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
BURST
60
40
20
0
50 100 150 200 250 300
R_BURST (kΩ)
3458 G04
Current Limit Accuracy
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 ^5VOUT
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
Burst Mode Quiescent Current
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
3458f
3