Product overview
Description
The L4981 I.C. 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 anyline switch. This new PFC offers the possibility to work at fixed frequency (L4981A) or modulated frequency (L4981B) optimizing the size of the input filter; both the operating frequency modes 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. The overcurrent level can be programmed using simple resistor for L4981A. For a better precision and for L4981B an external divider must be used.
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All features
- PRECISE 2% ON CHIP REFERENCE EXTERNALLY AVAILABLE
- OVERVOLTAGE, OVERCURRENT PROTECTION
- SOFT START
- LOW START-UP CURRENT (0.3mA TYP.)
- HIGH CURRENT BIPOLAR AND DMOS TOTEM POLE OUTPUT
- CONTROL BOOST PWM UP TO 0.99P.F.
- UNIVERSAL INPUT MAINS
- LIMIT LINE CURRENT DISTORTION TO < 5%
- AVERAGE CURRENT MODE PWM FOR MINIMUM NOISE SENSITIVITY
- UNDER VOLTAGE LOCKOUT WITH HYSTERESIS AND PROGRAMMABLE TURN ON THRESHOLD
- FEED FORWARD LINE AND LOAD REGULATION
Circuit Diagram
All resources
Resource title | Version | Latest update |
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Product Specifications (1)
Resource title | Version | Latest update | ||
---|---|---|---|---|
6.2 | 19 Sep 2016 | 19 Sep 2016 |
Application Notes (5 of 9)
Resource title | Version | Latest update | ||
---|---|---|---|---|
3.3 | 02 Aug 2022 | 02 Aug 2022 | ||
3.2 | 20 May 2024 | 20 May 2024 | ||
1.2 | 02 Aug 2022 | 02 Aug 2022 | ||
2.0 | 20 May 2024 | 20 May 2024 | ||
1.3 | 20 May 2024 | 20 May 2024 | ||
9.4 | 20 May 2024 | 20 May 2024 | ||
1.1 | 23 Apr 2021 | 23 Apr 2021 | ||
1.2 | 13 Sep 2018 | 13 Sep 2018 | ||
3.3 | 23 Apr 2021 | 23 Apr 2021 |
Presentations (1)
Resource title | Version | Latest update | ||
---|---|---|---|---|
24 Feb 2016 | 24 Feb 2016 |
EDA Symbols, Footprints and 3D Models
STMicroelectronics - L4981
Speed up your design by downloading all the EDA symbols, footprints and 3D models for your application. You have access to a large number of CAD formats to fit with your design toolchain.
Please select one model supplier :
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Symbols
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Footprints
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3D models
Quality and Reliability
Part Number | Marketing Status | Package | Grade | RoHS Compliance Grade | Material Declaration** |
---|---|---|---|---|---|
L4981AD | Active | SO-20 | Industrial | Ecopack2 | |
L4981AD013TR | Active | SO-20 | Industrial | Ecopack2 | |
L4981BD | Active | SO-20 | Industrial | Ecopack2 | |
L4981BD013TR | Active | SO-20 | Industrial | Ecopack2 |
Marketing Status
Package
SO-20
Grade
Industrial
RoHS Compliance Grade
Ecopack2
Marketing Status
Package
SO-20
Grade
Industrial
RoHS Compliance Grade
Ecopack2
Marketing Status
Package
SO-20
Grade
Industrial
RoHS Compliance Grade
Ecopack2
(**) The Material Declaration forms available on st.com may be generic documents based on the most commonly used package within a package family. For this reason, they may not be 100% accurate for a specific device. Please contact our sales support for information on specific devices.
Sample & Buy
Part Number | Marketing Status | Budgetary Price (US$)*/Qty | Order from ST | Order from distributors | Package | Packing Type | RoHS | Country of Origin | ECCN (US) | ECCN (EU) | Operating Temperature (°C) (min) | Operating Temperature (°C) (max) | |||||||||||||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
L4981BD | Active | 1.4973 / 1k | Available at 3 distributors Distributor availability of L4981BD
Distributor reported inventory date: 2/21/2025 | | | | Buy from Distributor | | SO-20 | Tube | MALAYSIA | EAR99 | NEC | ||||||||||||||||||||||||||||||
L4981BD013TR | Active | 1.4973 / 1k | Available at 4 distributors Distributor availability of L4981BD013TR
Distributor reported inventory date: 2/21/2025 | | | | Buy from Distributor | | SO-20 | Tape and Reel | MALAYSIA | EAR99 | NEC | ||||||||||||||||||||||||||||||
L4981AD | Active | 1.3096 / 1k | Available at 3 distributors Distributor availability of L4981AD
Distributor reported inventory date: 2/21/2025 | | | | Buy from Distributor | | SO-20 | Tube | MALAYSIA | EAR99 | NEC | ||||||||||||||||||||||||||||||
L4981AD013TR | Active | 1.3096 / 1k | Available at 4 distributors Distributor availability of L4981AD013TR
Distributor reported inventory date: 2/21/2025 | | | | Buy from Distributor | | SO-20 | Tape and Reel | MALAYSIA | EAR99 | NEC |
L4981BD Active
Part Number:
L4981BD
Farnell Element14
Stock
2269Min.Order
1MOUSER
Stock
1666Min.Order
1DIGIKEY
Stock
753Min.Order
1Distributor reported inventory date: 2/21/2025
Stock
Min.Order
L4981BD013TR Active
Part Number:
L4981BD013TR
Farnell Element14
Stock
2818Min.Order
1MOUSER
Stock
2710Min.Order
1DIGIKEY
Stock
1675Min.Order
1Newark Element14
Stock
114Min.Order
0Distributor reported inventory date: 2/21/2025
Stock
Min.Order
L4981AD Active
Part Number:
L4981AD
ANGLIA Live
Stock
3800Min.Order
1MOUSER
Stock
2792Min.Order
1DIGIKEY
Stock
509Min.Order
1Distributor reported inventory date: 2/21/2025
Stock
Min.Order
L4981AD013TR Active
Part Number:
L4981AD013TR
Farnell Element14
Stock
550Min.Order
1MOUSER
Stock
2009Min.Order
1DIGIKEY
Stock
1866Min.Order
1YOSUN
Stock
100Min.Order
1Distributor reported inventory date: 2/21/2025
Stock
Min.Order
(*) Suggested Resale Price (USD) per defined quantity for BUDGETARY USE ONLY. For quotes, prices in local currency, please contact your local ST Sales Office or our Distributors