L4981B

The L4981B is a Power Factor Corrector provides the necessary features to achieve a very high power factor up to 0.99. Realized in BCD 60II technology this power factor corrector (PFC) pre-regulator contains all the control functions for designing a high efficiency-mode power supply with sinusoidal line current consumption. The L4981 can be easily used in systems with mains voltages between 85V to 265V without any line switch. This new PFC offers modulated frequency optimizing the size of the input filter; the operating frequency mode working with an average current-mode PWM controller, maintaining sinusoidal line current without slope compensation. Besides power MOSFET gate driver, precise voltage reference (externally available), error amplifier, under-voltage lockout, current sense and the soft start are included. To limit the number of the external components, the device integrates protections as overvoltage and overcurrent.

• Limit line current distortion to <lt/>5%
• Universal input mains
• Feed forward line and load regulation
• Average current mode PWM for minimum noise sensitivity
• High current bipolar and DMOS totem pole output
• Under voltage lockout with hysteresis and programmable turn on
• Threshold overvoltage, overcurrent protection
• Precise 2% on chip reference externally available
• Soft-start