POWER LOSS (W)
LTC3769
60V Low I Synchronous
Q
Boost Controller
FEATURES DESCRIPTION
n
Synchronous Operation for Highest Efficiency and The LTC 3769 is a high performance single output syn-
Reduced Heat Dissipation chronous boost converter controller that drives an all
n
Wide V Range: 4.5V to 60V (65V Abs Max); N-channel power MOSFET stage. Synchronous rectifica-
IN
Operates Down to 2.3V After Start-Up tion increases efficiency, reduces power losses and eases
n
Output Voltage Up to 60V thermal requirements, simplifying high power boost ap-
n
1% 1.200V Reference Voltage plications. The 28A no-load quiescent current extends
n
R or Inductor DCR Current Sensing operating run time in battery-powered systems.
SENSE
n
100% Duty Cycle Capability for Synchronous MOSFET
A 4.5V to 60V input supply range encompasses a wide
n
Low Quiescent Current: 28A
range of system architectures and battery chemistries.
n
Phase-Lockable Frequency (75kHz to 850kHz)
When biased from the output of the boost converter or
n
Programmable Fixed Frequency (50kHz to 900kHz)
another auxiliary supply, the LTC3769 can operate from an
n
Power Good Output Voltage Monitor
input supply as low as 2.3V after start-up. The operating
n
Low Shutdown Current: 4A
frequency can be set within a 50kHz to 900kHz range or
n
Internal LDO Powers Gate Drive from VBIAS or EXTV
CC
synchronized to an external clock using the internal PLL.
n
Thermally Enhanced Low Profile 24-Pin 4mm 4mm
The SS pin ramps the output voltage during start-up. The
QFN Package and 20-Lead TSSOP Package
operation, pulse-
PLLIN/MODE pin selects Burst Mode
skipping mode or forced continuous mode at light loads.
APPLICATIONS
L, LT, LTC, LTM, Burst Mode, OPTI-LOOP, Linear Technology and the Linear logo are registered
n
Industrial trademarks of Linear Technology Corporation. All other trademarks are the property of their
respective owners. Protected by U. S. Patents, including 5408150, 5481178, 5705919,
n
Automotive
5929620, 6177787, 6498466, 6580258, 6611131.
n
Medical
n
Military
TYPICAL APPLICATION
120W, 12V to 24V/5A Synchronous Boost Converter Efficiency and Power Loss
vs Output Current
3.3H 100 10
4m
V
V
IN OUT
4.5V TO 60V
24V/5A
22F 220F 90
DOWN TO 2.3V
VBIAS
AFTER START-UP IF
EFFICIENCY 1
+
RUN SENSE
VBIAS IS POWERED
10nF 80
V FOLLOWS V FOR V > 24V
FROM V OUT IN IN
OUT
SS
SENSE
LTC3769 BG
8.66K POWER
15nF 70 0.1
ITH
LOSS
100pF TG
60
SW 0.01
PLLIN/MODE
50
0.1F
FREQ
BOOST
40 0.001
OVMODE
0.0001 0.001 0.01 0.1 1 10
INTV OUTPUT CURRENT (A)
CC
ILIM
3769 TA01b
4.7F
232k
VFB
PGOOD
EXTV
CC
12.1k
GND
3769 TA01a
3769fa
1
For more information www.linear.com/LTC3769
EFFICIENCY (%)LTC3769
(Notes 1, 3)
ABSOLUTE MAXIMUM RATINGS
VBIAS ........................................................ 0.3V to 65V EXTV ...................................................... 0.3V to 14V
CC
+
BOOST ........................................................0.3V to 71V SENSE , SENSE ........................................ 0.3V to 65V
+
SW ................................................................ 5V to 65V (SENSE - SENSE ) ............................................0.3V to 0.3V
RUN ............................................................. 0.3V to 8V ILIM, SS, ITH, FREQ, PHASMD, VFB .....0.3V to INTV
CC
Maximum Current Sourced into Pin Operating Junction Temperature
From Source >8V ..............................................100A Range (Note 2) ........................................55C to 150C
PGOOD, PLLIN/MODE ................................. 0.3V to 6V Storage Temperature Range .................. 65C to 150C
INTV , (BOOST - SW) ..................................0.3V to 6V Lead Temperature (Soldering, 10 sec) SSOP ........300C
CC
PIN CONFIGURATION
TOP VIEW
TOP VIEW
ILIM 1 20 PGOOD
24 23 22 21 20 19
INTV 2 19 VBIAS
CC
VBIAS 1 18 SW
FREQ 3 18 EXTV
CC
PGOOD 2 17 OVMODE
GND 4 17 INTV
CC
ILIM 3 16 ITH
25
PLLIN/MODE 5 16 BG
21
GND
NC 4 15 VFB
GND
RUN 6 15 BOOST
+
INTV 5 14 SENSE
CC
SS 7 14 TG
NC 6 13 SENSE
SENSE 8 13 SW
7 8 9 10 11 12
+
SENSE 9 12 OVMODE
VFB 10 11 ITH
FE PACKAGE
20-LEAD PLASTIC TSSOP
UF PACKAGE
T = 150C, = 38C/W
JMAX JA
24-LEAD (4mm 4mm) PLASTIC QFN
EXPOSED PAD (PIN 21) IS GND, MUST BE SOLDERED TO PCB
T = 150C, = 47C/W
JMAX JA
EXPOSED PAD (PIN 25) IS GND, MUST BE SOLDERED TO PCB
ORDER INFORMATION
LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE
LTC3769EUF#PBF LTC3769EUF#TRPBF 3769 24-Lead (4mm 4mm) Plastic QFN 40C to 125C
LTC3769IUF#PBF LTC3769IUF#TRPBF 3769 24-Lead (4mm 4mm) Plastic QFN 40C to 125C
LTC3769HUF#PBF LTC3769HUF#TRPBF 3769 40C to 150C
24-Lead (4mm 4mm) Plastic QFN
LTC3769MPUF#PBF LTC3769MPUF#TRPBF 3769 55C to 150C
24-Lead (4mm 4mm) Plastic QFN
LTC3769EFE#PBF LTC3769EFE#TRPBF LTC3769FE 20-Lead Plastic SSOP 40C to 125C
LTC3769IFE#PBF LTC3769IFE#TRPBF LTC3769FE 20-Lead Plastic SSOP 40C to 125C
LTC3769HFE#PBF LTC3769HFE#TRPBF LTC3769FE 20-Lead Plastic SSOP 40C to 150C
LTC3769MPFE#PBF LTC3769MPFE#TRPBF LTC3769FE 20-Lead Plastic SSOP 55C to 150C
Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container.
For more information on lead free part marking, go to: