LM5035A Datasheet, PDF (1/30 Pages) National Semiconductor (TI) – PWM Controller with Integrated Half-Bridge and SyncFET PWM Controller with Integrated Half-Bridge and SyncFET

LM5035A/LM5035A-1
July 30, 2010
PWM Controller with Integrated Half-Bridge and SyncFET
Drivers
General Description
The LM5035A 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 LM5035A is a functional variant of the
LM5035 half-bridge PWM controller. The VCC current limit
threshold has been increased to 35 mA. The soft start and
soft start currents have been increased from 50 µA to 100 µA.
The BST UV threshold has been lowered to less than the VCC
UV threshold. The ratio of the T1 and T2 delays on the SR1
and SR2 outputs has been increased from 2:1 to 3:1. The
floating high-side gate driver 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. The differences
between LM5035, LM5035A, LM5035B, and LM5035C are
summarized in Table 2.
Features
■ ^{105V / 2A Half-Bridge Gate Drivers}
■ ^{Synchronous Rectifier Control Outputs with}
Programmable Delays
■ ^{High Voltage (105V) Start-up Regulator}
■ ^{Voltage mode Control with Line Feed-Forward and Volt •}
Second Limiting
■ ^{Resistor Programmed, 2MHz Capable Oscillator}
■ ^{Patent Pending Oscillator Synchronization}
■ ^{Programmable Line Under-Voltage Lockout}
■ ^{Line 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
■ ^{LLP-24 (4mm x 5mm)}
■ ^{TSSOP-28EP (LM5035A-1 only)}
Simplified Application Diagram
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