Datasheet
LTC3458L
3
3458lfa
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 (I
BURSTPEAK
)R
ILIM
= 84.5k 0.55 A
BURST Threshold Voltage 1.10 V
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.
ELECTRICAL CHARACTERISTICS
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 LTC3458LE 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
UW
I
LIMIT
, I
BURSTPEAK
, I
ZERO
Currents
Burst Mode Quiescent Current
Maximum Load Current in Burst Oscillator Programming Resistor
Current Limit Accuracy
Typical Burst Mode Threshold and
Hysteresis vs R
BURST
(T
A
= 25°C unless otherwise specified)
TEMPERATURE (°C)TEMPERATURE (°C)V
IN
(V)
–402.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5
CURRENT (μA)
10
15
60
3458L G033458L G01 3458L G02
5
0
–15
10
35
85
20
CURRENT (mA)
2200
2000
1800
1600
1400
1200
1000
800
600
400
200
0
–200
I
LIMIT
I
BURSTPEAK
I
ZERO
I
VIN
I
VOUT
V
IN
= 3.3V
V
OUT
= 5V
3458L G04
3458L G05 3458L G06
R
BURST
(kΩ)
50
CURRENT (mA)
200
300
100 150 250
160
140
120
100
80
60
40
20
0
V
IN
(V)
1.5
CURRENT (mA)
300
250
200
150
100
50
0
3.0 4.0 4.5
2.0 2.5
3.5
OSCILLATOR FREQUENCY (kHz)
400
RT (kΩ)
600
550
500
450
400
350
300
250
200
150
100
1200
600
800
1000
1400
OUT OF
BURST
INTO
BURST
3.3V
OUT
5V
OUT
R
ILIM
= 84.5k
–45
1.85
CURRENT (A)
1.95
2.15
2.25
–15
15
30 90
2.05
–30 0
45
60
75
R
ILIMIT
= 84.5k
V
OUT
= 5V
L = 7.4μH
R
LIM
= 84.5k