LT3758/LT3758A
High Input Voltage,
Boost, Flyback, SEPIC and
Inverting Controller
Fe A
Description
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Wide Input Voltage Range: 5.5V to 100V
The LT 3758/LT3758A are wide input range, current
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Positive or Negative Output Voltage Programming
mode, DC/DC controllers which are capable of generating
with a Single Feedback Pin
either positive or negative output voltages. They can be
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Current Mode Control Provides Excellent Transient
configured as either a boost, flyback, SEPIC or inverting
Response
converter. The LT3758/LT3758A drive a low side external
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Programmable Operating Frequency (100kHz to
N-channel power MOSFET from an internal regulated 7.2V
1MHz) with One External Resistor
supply. The fixed frequency, current-mode architecture
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Synchronizable to an External Clock
results in stable operation over a wide range of supply
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Low Shutdown Current < 1A
and output voltages.
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Internal 7.2V Low Dropout Voltage Regulator
The operating frequency of LT3758/LT3758A can be set
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Programmable Input Undervoltage Lockout with
with an external resistor over a 100kHz to 1MHz range,
Hysteresis
and can be synchronized to an external clock using the
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Programmable Soft-Start
SYNC pin. A minimum operating supply voltage of 5.5V,
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Small 10-Lead DFN (3mm 3mm) and
and a low shutdown quiescent current of less than 1A,
MSOPE Packages
make the LT3758/LT3758A ideally suited for battery-
powered systems.
Applic A
The LT3758/LT3758A feature soft-start and frequency
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Automotive
foldback functions to limit inductor current during start-
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Telecom
up and output short-circuit. The LT3758A has improved
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Industrial
load transient performance compared to the LT3758.
L, LT, LTC, LTM, Linear Technology, the Linear logo and Burst Mode are registered trademarks
and No R and ThinSOT are trademarks of Analog Devices, Inc. All other trademarks are the
SENSE
property of their respective owners. Patents pending.
t Al Applic A
12V Output Nonisolated Flyback Power Supply
D1
V
V
IN OUT
36V TO 12V
0.022F
C
72V
IN 6.2k 1.2A
100V
2.2F 1M
T1
4,5,6
100V
1,2,3
(PARALLEL)
V
IN
X7R
(SERIES)
D
SN
SHDN/UVLO
44.2k
SW
LT3758 105k
SYNC GATE
M1 1%
SENSE
RT
SS
FBX
63.4k
V GND INTV
C CC
200kHz
1N4148
5.1
0.47F
C
VCC
10k
C
15.8k OUT
100pF
4.7F 0.030
47F
1%
10V
10nF
X5R
X5R
3758 TA01
3758afe
1
For more information www.linear.com/LT3758
tion ypic
tions
turesLT3758/LT3758A
Absolute M A Mu M rA (Note 1)
V , SHDN/UVLO (Note 7) ......................................100V Operating Junction Temperature Range (Notes 2, 8)
IN
INTV ....................................................V + 0.3V, 20V LT3758E/LT3758AE ........................... 40C to 125C
CC IN
GATE ........................................................ INTV + 0.3V LT3758I/LT3758AI ............................. 40C to 125C
CC
SYNC ..........................................................................8V LT3758H/LT3758AH .......................... 40C to 150C
V , SS .........................................................................3V LT3758MP/LT3758AMP ..................... 55C to 150C
C
RT 1.5V Storage Temperature Range
...............................................................................................
SENSE ....................................................................0.3V DFN .................................................... 65C to 125C
FBX ................................................................. 6V to 6V MSOP ................................................ 65C to 150C
Lead Temperature (Soldering, 10 sec) MSOP ........300C
p in c F A
TOP VIEW
TOP VIEW
V 1 10 V
C IN
V 1 10 V
C IN
FBX 2 9 SHDN/UVLO
FBX 2 9 SHDN/UVLO
11 SS 3 11 8 INTV
SS 3 8 INTV
CC
CC
RT 4 7 GATE
RT 4 7 GATE
SYNC 5 6 SENSE
SYNC 5 6 SENSE
MSE PACKAGE
10-LEAD PLASTIC MSOP
DD PACKAGE
T = 150C, = 40C/W
JMAX JA
10-LEAD (3mm 3mm) PLASTIC DFN
EXPOSED PAD (PIN 11) IS GND, MUST BE SOLDERED TO PCB
T = 125C, = 43C/W
JMAX JA
EXPOSED PAD (PIN 11) IS GND, MUST BE SOLDERED TO PCB
o r Der i n F MA