Key facts
- Brand
- STMicroelectronics
- Model
- L4981
- Category
- Power Management
- Documents
- 3
- Languages
- EN
- Last added
- 2012-08-10
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ST L4981A L4981B POWER FACTOR CORRECTOR handbook
The L4981A L4981B power factor corrector controller can achieve a power factor of up to 0.99. It also limits line current distortion to less than 5%. The chip is made using BCD 60II technology and has all the features of a power factor corrector (PFC) pre-regulator, including line and load regulation, average current mode PWM, high current bipolar and DMOS totem pole output, low start-up current (typ. 0.3 mA), undervoltage lockout with hysteresis and programmable turn-on threshold, overvoltage, overcurrent protection, precise 2% on-chip reference, and external soft start.
Read onlineSTMicroelectronics L4981 specifications
| Controller Driver Output Current | 1.5A |
|---|---|
| Input Voltage Range (Feed-forward) | 88V to 264V |
| Controller Off-Time Minimum | 5% of period |
Source: AN1606 Bridgeless PFC Configuration Using L4981 Controller Application Note
All STMicroelectronics L4981 documents by type
How to use the product for one specific task, with worked examples.
Questions answered in these manuals
What are the advantages of the bridgeless PFC configuration?
The topology offers increased efficiency and improved thermal management by eliminating the input rectifier bridge.
From: AN1606 Bridgeless PFC Configuration Using L4981 Controller Application Note
How is current sensed in high power bridgeless applications?
A magnetic current transformer is preferred over a simple resistor to handle the continuously changing current direction and reduce dissipation.
From: AN1606 Bridgeless PFC Configuration Using L4981 Controller Application Note
What is the maximum power factor improvement achievable with this preregulator?
The preregulator can improve the power factor up to 0.99.
From: STMicroelectronics AN628 Designing High Power Factor Preregulator with L4981
What is the minimum switching frequency for the L4981?
The device allows for a switching frequency higher than 200 kHz.
From: STMicroelectronics AN628 Designing High Power Factor Preregulator with L4981