Key facts
- Brand
- STMicroelectronics
- Model
- L4981B
- Category
- Power Management
- Documents
- 2
- 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 onlineAll STMicroelectronics L4981B documents by type
How to use the product for one specific task, with worked examples.
Questions answered in these manuals
What is the purpose of frequency modulation on the L4981B?
It spreads the noise spectrum over a wider range to reduce the peak of the associated energy and help meet EMI requirements.
From: STMicroelectronics AN833 L4981B Frequency Modulation Application Note
Which pin is used for frequency modulation on the L4981B?
Pin 16, which is named FREQ-MOD in this version, is used to perform the frequency modulation function.
From: STMicroelectronics AN833 L4981B Frequency Modulation Application Note