LM5021MM-1/NOPB Power Path Management IC AC/DC Converters AC-DC Crnt Mode PWM Cntlr

1 Features

• Ultra-low Startup Current (25 μA Maximum)

• Current Mode Control

• Skip Cycle Mode for Low Standby Power

• Single Resistor Programmable Oscillator

• Synchronizable Oscillator

• Adjustable Soft-Start

• Integrated 0.7-A Peak Gate Driver

• Direct Opto-Coupler Interface

• Maximum Duty Cycle Limiting (80% for LM5021-1 or 50% for LM5021-2)

• Slope Compensation (LM5021-1 Only)

• Undervoltage Lockout (UVLO) with Hysteresis

• Cycle-by-Cycle Overcurrent Protection

• Hiccup Mode for Continuous Overload Protection

• Leading Edge Blanking of Current Sense Signal

• Packages: VSSOP-8 or PDIP-8

2 Applications

• DCM/CCM Flyback Converters

• Industrial Power Conversion

• SMPS for Smart Meters and Audio Amplifiers

• Building Automation and White Goods SMPS

• Isolated Telecom Power Supplies

The LM5021 off-line pulse width modulation (PWM) controller contains all of the features needed to implement highly efficient off-line single-ended flyback and forward power converters using current- mode control. The LM5021 features include an ultra- low (25 μA) start-up current, which minimizes power losses in the high voltage start-up network. A skip cycle mode reduces power consumption with light loads for energy conserving applications (ENERGY STAR®, CECP, and so forth). Additional features include under-voltage lockout, cycle-by-cycle current limit, hiccup mode overload protection, slope compensation, soft-start and oscillator synchronization capability. This high performance 8- pin IC has total propagation delays less than 100 ns and a 1-MHz capable oscillator that is programmed with a single resistor.

Device Information