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

Packages

n

MSOP-10

n

LLP-10 (4 mmx4mm)

Connection Diagram

Top View

20095001

10-Lead MSOP, LLP

Ordering Information

Order Number

Description

NSC Package Drawing

Supplied As

LM5020MM-1

MSOP, 80% Duty Cycle Limit

MUB-10A

1000 Units on Tape and Reel

LM5020MMX-1

MSOP, 80% Duty Cycle Limit

MUB-10A

3500 Units on Tape and Reel

LM5020SD-1

LLP, 80% Duty Cycle Limit

SDC-10A

1000 Units on Tape and Reel

LM5020SDX-1

LLP, 80% Duty Cycle Limit

SDC-10A

4500 Units on Tape and Reel

LM5020MM-2

MSOP, 50% Duty Cycle Limit

MUB-10A

1000 Units on Tape and Reel

LM5020MMX-2

MSOP, 50% Duty Cycle Limit

MUB-10A

3500 Units on Tape and Reel

LM5020SD-2

LLP, 50% Duty Cycle Limit

SDC-10A

1000 Units on Tape and Reel

LM5020SDX-2

LLP, 50% Duty Cycle Limit

SDC-10A

4500 Units on Tape and Reel

October 2004

© 2004 National Semiconductor Corporation

DS200950

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