LM5020_06 Datasheet, PDF (1/13 Pages) National Semiconductor (TI) – 100V Current Mode PWM Controller

April 2006
LM5020
100V Current Mode PWM Controller
General Description
The LM5020 high voltage pulse-width-modulation (PWM)
controller contains all of the features needed to implement
single ended primary power converter topologies. Output
voltage regulation is based on current-mode control, which
eases the design of loop compensation while providing in-
herent line feed-forward. The LM5020 includes a high-
voltage start-up regulator that operates over a wide input
range up to 100V. The PWM controller is designed for high
speed capability including an oscillator frequency range to
1MHz and total propagation delays less than 100ns. Addi-
tional features include an error amplifier, precision reference,
line under-voltage lockout, cycle-by-cycle current limit, slope
compensation, softstart, oscillator synchronization capability
and thermal shutdown. The controller is available in both
MSOP-10 and LLP-10 packages.
Features
n Internal Start-up Bias Regulator
n Error Amplifier
n Precision Voltage Reference
n Programmable Softstart
n 1A Peak Gate Driver
n Maximum Duty Cycle Limiting (80% for LM5020-1 or
50% for LM5020-2)
n Programmable Line Under Voltage Lockout (UVLO) with
Adjustable Hysteresis
n Cycle-by-Cycle Over-Current Protection
n Slope Compensation (LM5020-1)
n Programmable Oscillator Frequency with
Synchronization Capability
n Current Sense Leading Edge Blanking
n Thermal Shutdown Protection
Applications
n Telecommunication Power Converters
n Industrial Power Converters
n +42V Automotive Systems
Packages
n MSOP-10
n LLP-10 (4 mm x 4 mm)
Typical Application Circuit
Non-Isolated Flyback Converter
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