LTC3721-1
Push-Pull PWM Controller
FEATURES
■ High Efficiency Push-Pull PWM
■ 1.5A Sink, 1A Source Output Drivers
■ Adjustable Push-Pull Dead-Time
■ Adjustable System Undervoltage Lockout and
Hysteresis
■ Adjustable Leading Edge Blanking
■ Low Start-Up and Quiescent Currents
■ Current Mode Operation
■ Single Resistor Slope Compensation
■ VCC UVLO and 25mA Shunt Regulator
■ Programmable Fixed Frequency Operation to 1MHz
■ Soft-Start, Cycle-by-Cycle Current Limiting and
Hiccup Mode Short-Circuit Protection
■ 5V, 15mA Low Dropout Regulator
■ 16-Pin SSOP and (4mm × 4mm) QFN Packages
U
APPLICATIO S
■ Telecommunications, Infrastructure Power Systems
■ Distributed Power Architectures
■ Server Power Supplies
■ High Density Power Modules
DESCRIPTIO
The LTC®3721-1 push-pull PWM controller provides all of
the control and protection functions necessary for com-
pact and highly efficient, isolated power converters. High
integration minimizes external component count, while
preserving design flexibility.
The robust push-pull output stages switch at half the
oscillator frequency. Dead-time is independently pro-
grammed with an external resistor. A UVLO program input
provides precise system turn-on and turn off voltages. The
LTC3721-1 features peak current mode control with pro-
grammable slope compensation and leading edge
blanking.
The LTC3721-1 features extremely low operating and
start-up currents and reliable short-circuit and
overtemperature protection. The LTC3721-1 is offered in
16-pin SSOP and (4mm × 4mm) QFN packages.
, LTC and LT are registered trademarks of Linear Technology Corporation.
TYPICAL APPLICATIO
VIN
Isolated Push-Pull Converter
FROM
AUXILIARY
WINDING
VREF
UVLO
DRVA
DRVB
VCC
CS
DPRG
LTC3721-1
CT
RLEB
VREF
SS
COMP
FB GND
RCS
VOUT
VOUT
V+
COLL
COMP
LT1431
RTOP
RREF
RMID
GND-F GND-S
VOUT
+
37211 TA01
sn37211 37211fs
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