LTC3722-1/LTC3722-2
Synchronous Dual Mode
Phase Modulated
Full Bridge Controllers
FEATURES DESCRIPTION
n
Adaptive or Manual Delay Control for Zero Voltage
The LTC 3722-1/LTC3722-2 phase-shift PWM controllers
Switching Operation
provide all of the control and protection functions neces-
n
Adjustable Synchronous Rectification T iming for
sary to implement a high efficiency, zero voltage switched
Highest Efficiency
(ZVS), full bridge power converter. Adaptive ZVS circuitry
n
Adjustable Maximum ZVS Delay
delays the turn-on signals for each MOSFET independent
n
Adjustable System Undervoltage Lockout Hysteresis
of internal and external component tolerances. Manual
n
Programmable Leading Edge Blanking
delay set mode enables secondary side control operation
n
Very Low Start-Up and Quiescent Currents
or direct control of switch turn-on delays.
n
Current Mode (LTC3722-1) or Voltage Mode
The LTC3722-1/LTC3722-2 feature adjustable synchron-
(LTC3722-2) Operation
ous rectiefi r timing for optimal efcfi iency. A UVLO program
n
Programmable Slope Compensation
input provides accurate system turn-on and turn-off
n
V UVLO and 25mA Shunt Regulator
CC
voltages. The LTC3722-1 features peak current mode
n
50mA Output Drivers
control with programmable slope compensation and
n
Soft-Start, Cycle-by-Cycle Current Limiting and
leading edge blanking, while the LTC3722-2 employs
Hiccup Mode Short-Circuit Protection
voltage mode control.
n
5V, 15mA Low Dropout Regulator
n
The LTC3722-1/LTC3722-2 feature extremely low operating
24-Pin Surface Mount GN Package
and start-up currents. Both devices include a full range of
protection features and are available in the 24-pin surface
APPLICATIONS
mount GN package.
n
Telecommunications, Infrastructure Power Systems
All registered trademarks and trademarks are the property of their respective owners.
n
Distributed Power Architectures
n
Server Power Supplies
TYPICAL APPLICATION
V
IN
36V TO
C
IN R1
72V
12V , 240W Converter Efficiency
OUT
U1 U2
MA MC 95
T1
36V
IN
L1
LTC3722
V 90
OUT
12V
48V
IN
L2
72V
IN
C
MB MD OUT 85
RCS
80
ME
T2
75
C1 U3
0 2 4 6 8 10 12 14 16 18 20
MF
CURRENT (A)
372212 TA01b
U1, U2: LTC4440 GATE DRIVER
U3: LTC3901 GATE DRIVER
372212 TA01a
Rev C
1
Document Feedback For more information www.analog.com
EFFICIENCY (%)LTC3722-1/LTC3722-2
ABSOLUTE MAXIMUM RATINGS (Note 1)
V to GND (Low Impedance Source) ........ 0.3V to 10V
CC V Output Current ................................. Self Regulated
REF
(Chip Self Regulates at 10.3V)
Outputs (A, B, C, D, E, F) Current .......................100mA
UVLO to GND ..............................................0.3V to V
CC Operating Junction Temperature Range
All Other Pins to GND
(Note 6) .................................................. 40C to 150C
(Low Impedance Source) .......................... 0.3V to 5.5V
Storage Temperature Range .................. 65C to 150C
V (Current Fed) ...................................................25mA
CC Lead Temperature (Soldering, 10 sec) ...................300C
PIN CONFIGURATION
LTC3722-1 LTC3722-2
TOP VIEW TOP VIEW
SYNC 1 24 C SYNC 1 24 C
T T
DPRG 2 23 GND RAMP 2 23 GND
CS 3 22 PGND CS 3 22 PGND
COMP 4 21 OUTA COMP 4 21 OUTA
RLEB 5 20 OUTB DPRG 5 20 OUTB
FB 6 19 OUTC FB 6 19 OUTC
SS 7 18 V SS 7 18 V
CC CC
NC 8 17 OUTD NC 8 17 OUTD
PDLY 9 16 OUTE PDLY 9 16 OUTE
SBUS 10 15 OUTF SBUS 10 15 OUTF
ADLY 11 14 V ADLY 11 14 V
REF REF
UVLO 12 13 SPRG UVLO 12 13 SPRG
GN PACKAGE GN PACKAGE
24-LEAD NARROW PLASTIC SSOP 24-LEAD NARROW PLASTIC SSOP
T = 125C, = 100C/W T = 125C, = 100C/W
JMAX JA JMAX JA
ORDER INFORMATION
LEAD FREE FINISH TAPE AND REEL PART MARKING PACKAGE DESCRIPTION TEMPERATURE RANGE
LTC3722EGN-1#PBF LTC3722EGN-1#TRPBF LTC3722EGN-1 24-Lead Plastic SSOP 40C to 85C
LTC3722EGN-2#PBF LTC3722EGN-2#TRPBF LTC3722EGN-2 24-Lead Plastic SSOP 40C to 85C
LTC3722IGN-1#PBF LTC3722IGN-1#TRPBF LTC3722IGN-1 24-Lead Plastic SSOP 40C to 85C
LTC3722IGN-2#PBF LTC3722IGN-2#TRPBF LTC3722IGN-2 24-Lead Plastic SSOP 40C to 85C
LTC3722HGN-1#PBF LTC3722HGN-1#TRPBF LTC3722HGN-1 24-Lead Plastic SSOP 40C to 150C
Consult ADI Marketing for parts specified with wider operating temperature ranges.
Tape and reel specifications. Some packages are available in 500 unit reels through designated sales channels with #TRMPBF suffix.
Rev C
2
For more information www.analog.com