LTC3722EGN-1#PBF Linear Technology, LTC3722EGN-1#PBF Datasheet - Page 10

• Manufacturer Part Number: LTC3722EGN-1#PBF
• Description: IC CTLR PWM CURRENT-MODE 24SSOP
• Manufacturer: Linear Technology

Specifications of LTC3722EGN-1#PBF

• Pwm Type: Current Mode, Full Bridge
• Number Of Outputs: 1
• Frequency - Max: 1MHz
• Duty Cycle: 98.5%
• Voltage - Supply: 3.8 V ~ 10.3 V
• Buck: No
• Boost: No
• Flyback: No
• Inverting: No
• Doubler: No
• Divider: Yes
• Cuk: No
• Isolated: Yes
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 24-SSOP
• Frequency-max: 1MHz
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

operaTion
LTC3722-1/LTC3722-2
TiMing DiagraM
Phase-Shift Full Bridge PWM
Conventional full bridge switching power supply topologies
are often employed for high power, isolated DC/DC and
off-line converters. Although they require two additional
switching elements, substantially greater power and higher
efficiency can be attained for a given transformer size
compared to the more common single-ended forward and
flyback converters. These improvements are realized since
the full bridge converter delivers power during both parts
of the switching cycle, reducing transformer core loss
and lowering voltage and current stresses. The full bridge
converter also provides inherent automatic transformer
flux reset and balancing due to its bidirectional drive
configuration. As a result, the maximum duty cycle range
is extended, further improving efficiency. Soft-switching
variations on the full bridge topology have been proposed
to improve and extend its performance and application.
These zero voltage switching (ZVS) techniques exploit the
0
RAMP
COMP
OUTB
OUTC
OUTD
OUTA
OUTE
OUTF
NOTE: SHADED AREAS CORRESPOND TO POWER DELIVERY PULSES.
COMP
PASSIVE LEG
DELAY
SYNC TURN OFF
DELAY (PROGRAMMABLE)
generally undesirable parasitic elements present within the
power stage. The parasitic elements are utilized to drive
near lossless switching transitions for all of the external
power MOSFETs.
LTC3722-1/LTC3722-2 phase-shift PWM controllers pro-
vide enhanced performance and simplify the design task
required for a ZVS phase-shifted full bridge converter.
The primary attributes of the LTC3722-1/LTC3722-2 as
compared to currently available solutions include:
1. Truly adaptive and accurate (DirectSense
2. Fixed ZVS capability.
SYNC TURN OFF
DELAY (PROGRAMMABLE)
ZVS with programmable timeout.
Benefit: higher efficiency, higher duty cycle capability,
eliminates external trim.
Benefit: enables secondary-side control and simplifies
external circuit.
ACTIVE LEG
DELAY
COMP
TM
technology)
372212 TD01
372212fa