LM5035B Datasheet, PDF (1/28 Pages) National Semiconductor (TI) – PWM Controller with Integrated Half-Bridge and SyncFET Drivers

LM5035B
July 7, 2009
PWM Controller with Integrated Half-Bridge and SyncFET
Drivers
General Description
The LM5035B Half-Bridge Controller/Gate Driver contains all
of the features necessary to implement half-bridge topology
power converters using voltage mode control with line voltage
feed-forward.
The LM5035B is a functional variant of the LM5035A half-
bridge PWM controller. The LM5035B provides higher maxi-
mum duty cycle and higher start-up regulator output current
than the LM5035A or LM5035. Also, the Synchronous Recti-
fier drive outputs of the LM5035B are held low in shutdown
modes.
The LM5035, LM5035A, and LM5035B include a floating
high-side gate driver, which is capable of operating with sup-
ply voltages up to 105V. Both the high-side and low-side gate
drivers are capable of 2A peak. An internal high voltage start-
up regulator is included, along with programmable line un-
dervoltage lockout (UVLO) and overvoltage protection (OVP).
The oscillator is programmed with a single resistor to fre-
quencies up to 2MHz. The oscillator can also be synchronized
to an external clock. A current sense input and a pro-
grammable timer provide cycle-by-cycle current limit and ad-
justable hiccup mode overload protection.
Features
■ ^{105V / 2A Half-Bridge Gate Drivers}
■ ^{Synchronous Rectifier Control Outputs with}
Programmable Delays
■ ^{Synchronous Rectifiers Turned Off in Shutdown Modes.}
■ ^{Reduced Deadtime Between High and Low Side Drive for}
Higher Maximum Duty Cycle.
■ ^{High Voltage (105V) Start-up Regulator}
■ ^{Voltage mode Control with Line Feed-Forward and Volt}
Second Limiting
■ ^{Resistor Programmed, 2MHz Capable Oscillator}
■ ^{Programmable Line Under-Voltage Lockout and Over-}
Voltage Protection
■ ^{Internal Thermal Shutdown Protection}
■ ^{Adjustable Soft-Start}
■ ^{Versatile Dual Mode Over-Current Protection with Hiccup}
Delay Timer
■ ^{Cycle-by-Cycle Over-Current Protection}
■ ^{Direct Opto-coupler Interface}
■ ^{5V Reference Output}
Packages
■ ^{TSSOP-20EP (Thermally enhanced)}
■ ^{LLP-24 (4mm x 5mm)}
Simplified Application Diagram
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