LM5021

·Ultra Low Start-up Current (25 µA maximum)
· Current Mode Control
·Skip Cycle Mode for Low Standby Power
·Single Resistor Programmable Oscillator
· Synchronizable Oscillator
·Adjustable Soft-start
· Integrated 0.7A Peak Gate Driver
· Direct Opto-Coupler Interface
· Maximum Duty Cycle Limiting (80% for LM5021-1 or 50% for LM5021-2)
·Slope Compensation for (LM5021-1 Only)
·Under Voltage Lockout (UVLO) with Hysteresis
· Cycle-by-Cycle Over-Current Protection
· Hiccup Mode for Continuous Overload Protection
· Leading Edge Blanking of Current Sense Signal
· Packages: MSOP-8 or MDIP-8

VIN to GND ...............................................................................-0.3V to 30V
VIN Clamp Continuous Current .............................................................5mA
CS to GND ..............................................................................-0.3V to 1.25V
RT to GND .................................................................................-0.3V to 5.5V
All other pins to GND .................................................................-0.3V to 7.0V
ESD Rating (Note 2)
Human Body Model ..................................................................................2kV
Storage Temperature .......................................................-65°C to +150°C
Operating Junction Temperature ......................................................+150°C

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, etc.). 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 100nS and a 1MHz capable oscillator that is programmed with a single resistor.