Order from our eStore and our distributors

Buy now
Overview
Tools & Software
Resources
Solutions
Quality & Reliability
Sales Briefcase
eDesignSuite
Get Started
Sample & Buy
Partner products
  • The UC284xB family of control ICs provides the necessary features to implement off-line or DC to DC fixed frequency current mode control schemes with a minimal external parts count. Internally implemented circuits include a trimmed oscillator for precise DUTY CYCLE CONTROL under voltage lockout featuring start-up current less than 0.5mA, a precision reference trimmed for accuracy at the error amp input, logic to insure latched operation, a PWM comparator which also provides current limit control, and a totem pole output stage designed to source or sink high peak current. The output stage, suitable for driving N-Channel MOSFETs, is low in the off-state.

    Differences between members of this family are the under-voltage lockout thresholds and maximum duty cycle ranges. The UC2842B and UC2844B have UVLO thresholds of 16V (on) and 10V (off), ideally suited off-line applications The corresponding thresholds for the UC2843B and UC2845B are 8.5V and 7.9V. The UC2842B and UC2843B can operate to duty cycles approaching 100%. A range of the zero to < 50 % is obtained by the UC2844B and UC2845B by the addition of an internal toggle flip flop which blanks the output off every other clock cycle.

    Key Features

    • LOW START-UP AND OPERATING CURRENT
    • UNDERVOLTAGE LOCKOUT WITH HYSTERESIS
    • INTERNALLY TRIMMED REFERENCE WITH UNDERVOLTAGE LOCKOUT
    • CURRENT LIMITING
    • TRIMMED OSCILLATOR FOR PRECISE FREQUENCY CONTROL
    • CURRENT MODE OPERATION TO 500kHz
    • OSCILLATOR FREQUENCY GUARANTEED AT 250kHz
    • LATCHING PWM FOR CYCLE-BY-CYCLE
    • HIGH CURRENT TOTEM POLE OUTPUT
    • AUTOMATIC FEED FORWARD COMPENSATION

Circuit Diagram

Download Download

Sample & Buy

Part Number
Package
Packing Type
Marketing Status
Budgetary Price (US$)*
Quantity
ECCN (US)
Country of Origin
Order from Distributors
Order from ST
UC3842BD1013TR SO-8 Tape And Reel
Active
0.2772 1000 EAR99 MOROCCO Check Availability

Distributor availability ofUC3842BD1013TR

Distributor Name
Region Stock Min. Order Third party link
DIGIKEY WORLDWIDE 2329 1 Order Now
ARROW AMERICA 517 1 Order Now
MOUSER WORLDWIDE 2270 1 Order Now
Farnell Element14 EUROPE 4000 1 Order Now
RUTRONIK EUROPE 2500 2500 Order Now

Distributor reported inventory date: 2019-08-21

Distributor Name

DIGIKEY

Stock

2329

Min.Order

1

Region

WORLDWIDE Order Now

ARROW

Stock

517

Min.Order

1

Region

AMERICA Order Now

MOUSER

Stock

2270

Min.Order

1

Region

WORLDWIDE Order Now

Farnell Element14

Stock

4000

Min.Order

1

Region

EUROPE Order Now

RUTRONIK

Stock

2500

Min.Order

2500

Region

EUROPE Order Now

Distributor reported inventory date: 2019-08-21

Buy now
UC3842BD1 SO-8 Tube
Active
0.2772 1000 EAR99 MOROCCO Check Availability

Distributor availability ofUC3842BD1

Distributor Name
Region Stock Min. Order Third party link
DIGIKEY WORLDWIDE 3977 1 Order Now
ARROW EUROPE 3632 0 Order Now
Newark Element14 AMERICA 665 0 Order Now
MOUSER WORLDWIDE 2137 1 Order Now
Farnell Element14 EUROPE 1016 1 Order Now

Distributor reported inventory date: 2019-08-21

Distributor Name

DIGIKEY

Stock

3977

Min.Order

1

Region

WORLDWIDE Order Now

ARROW

Stock

3632

Min.Order

0

Region

EUROPE Order Now

Newark Element14

Stock

665

Min.Order

0

Region

AMERICA Order Now

MOUSER

Stock

2137

Min.Order

1

Region

WORLDWIDE Order Now

Farnell Element14

Stock

1016

Min.Order

1

Region

EUROPE Order Now

Distributor reported inventory date: 2019-08-21

Buy now
UC3842BN DIP-8 Tube
Active
0.2772 1000 EAR99 - Check Availability

Distributor availability ofUC3842BN

Distributor Name
Region Stock Min. Order Third party link
DIGIKEY WORLDWIDE 3488 1 Order Now
RS COMPONENTS EUROPE 720 10 Order Now
AVNET AMERICA 2000 0 Order Now
FUTURE WORLDWIDE 600 1 Order Now
ARROW EUROPE 2270 0 Order Now
ARROW AMERICA 3000 2000 Order Now
MOUSER WORLDWIDE 4817 1 Order Now
Farnell Element14 EUROPE 2124 1 Order Now
RUTRONIK EUROPE 100 50 Order Now

Distributor reported inventory date: 2019-08-21

Distributor Name

DIGIKEY

Stock

3488

Min.Order

1

Region

WORLDWIDE Order Now

RS COMPONENTS

Stock

720

Min.Order

10

Region

EUROPE Order Now

AVNET

Stock

2000

Min.Order

0

Region

AMERICA Order Now

FUTURE

Stock

600

Min.Order

1

Region

WORLDWIDE Order Now

ARROW

Stock

2270

Min.Order

0

Region

EUROPE Order Now

ARROW

Stock

3000

Min.Order

2000

Region

AMERICA Order Now

MOUSER

Stock

4817

Min.Order

1

Region

WORLDWIDE Order Now

Farnell Element14

Stock

2124

Min.Order

1

Region

EUROPE Order Now

RUTRONIK

Stock

100

Min.Order

50

Region

EUROPE Order Now

Distributor reported inventory date: 2019-08-21

Buy now

UC3842BD1013TR

Package

SO-8

Packing Type

Tape And Reel

Unit Price (US$)

0.2772*

Distributor availability ofUC3842BD1013TR

Distributor Name
Region Stock Min. Order Third party link
DIGIKEY WORLDWIDE 2329 1 Order Now
ARROW AMERICA 517 1 Order Now
MOUSER WORLDWIDE 2270 1 Order Now
Farnell Element14 EUROPE 4000 1 Order Now
RUTRONIK EUROPE 2500 2500 Order Now

Distributor reported inventory date: 2019-08-21

Distributor Name

DIGIKEY

Stock

2329

Min.Order

1

Region

WORLDWIDE Order Now

ARROW

Stock

517

Min.Order

1

Region

AMERICA Order Now

MOUSER

Stock

2270

Min.Order

1

Region

WORLDWIDE Order Now

Farnell Element14

Stock

4000

Min.Order

1

Region

EUROPE Order Now

RUTRONIK

Stock

2500

Min.Order

2500

Region

EUROPE Order Now

Distributor reported inventory date: 2019-08-21

Marketing Status

Active

Unit Price (US$)

0.2772

Quantity

1000

ECCN (US)

EAR99

Country of Origin

MOROCCO

UC3842BD1

Package

SO-8

Packing Type

Tube

Unit Price (US$)

0.2772*

Distributor availability ofUC3842BD1

Distributor Name
Region Stock Min. Order Third party link
DIGIKEY WORLDWIDE 3977 1 Order Now
ARROW EUROPE 3632 0 Order Now
Newark Element14 AMERICA 665 0 Order Now
MOUSER WORLDWIDE 2137 1 Order Now
Farnell Element14 EUROPE 1016 1 Order Now

Distributor reported inventory date: 2019-08-21

Distributor Name

DIGIKEY

Stock

3977

Min.Order

1

Region

WORLDWIDE Order Now

ARROW

Stock

3632

Min.Order

0

Region

EUROPE Order Now

Newark Element14

Stock

665

Min.Order

0

Region

AMERICA Order Now

MOUSER

Stock

2137

Min.Order

1

Region

WORLDWIDE Order Now

Farnell Element14

Stock

1016

Min.Order

1

Region

EUROPE Order Now

Distributor reported inventory date: 2019-08-21

Marketing Status

Active

Unit Price (US$)

0.2772

Quantity

1000

ECCN (US)

EAR99

Country of Origin

MOROCCO

UC3842BN

Package

DIP-8

Packing Type

Tube

Unit Price (US$)

0.2772*

Distributor availability ofUC3842BN

Distributor Name
Region Stock Min. Order Third party link
DIGIKEY WORLDWIDE 3488 1 Order Now
RS COMPONENTS EUROPE 720 10 Order Now
AVNET AMERICA 2000 0 Order Now
FUTURE WORLDWIDE 600 1 Order Now
ARROW EUROPE 2270 0 Order Now
ARROW AMERICA 3000 2000 Order Now
MOUSER WORLDWIDE 4817 1 Order Now
Farnell Element14 EUROPE 2124 1 Order Now
RUTRONIK EUROPE 100 50 Order Now

Distributor reported inventory date: 2019-08-21

Distributor Name

DIGIKEY

Stock

3488

Min.Order

1

Region

WORLDWIDE Order Now

RS COMPONENTS

Stock

720

Min.Order

10

Region

EUROPE Order Now

AVNET

Stock

2000

Min.Order

0

Region

AMERICA Order Now

FUTURE

Stock

600

Min.Order

1

Region

WORLDWIDE Order Now

ARROW

Stock

2270

Min.Order

0

Region

EUROPE Order Now

ARROW

Stock

3000

Min.Order

2000

Region

AMERICA Order Now

MOUSER

Stock

4817

Min.Order

1

Region

WORLDWIDE Order Now

Farnell Element14

Stock

2124

Min.Order

1

Region

EUROPE Order Now

RUTRONIK

Stock

100

Min.Order

50

Region

EUROPE Order Now

Distributor reported inventory date: 2019-08-21

Marketing Status

Active

Unit Price (US$)

0.2772

Quantity

1000

ECCN (US)

EAR99

Country of Origin

-

(*) Suggested Resale Price per unit (USD) for BUDGETARY USE ONLY. For quotes, prices in local currency, please contact your local ST Sales Office  or our Distributors

Recommended for you

00 Files selected for download

Technical Documentation

    • Description Version Size Action
      DS0908
      High performance current mode PWM controller
      3.3
      233.69 KB
      PDF
      DS0908

      High performance current mode PWM controller

    • Description Version Size Action
      AN246
      UC3842 provides low-cost current mode control
      1.3
      1.16 MB
      PDF
      AN246

      UC3842 provides low-cost current mode control

    • Description Version Size Action
      DT0118
      A Procedure for Restoring Bootloader Functionality to the STNRG388A
      1.0
      367.56 KB
      PDF
      DT0118

      A Procedure for Restoring Bootloader Functionality to the STNRG388A

Presentations & Training Material

    • Description Version Size Action
      Primary side regulation controllers portfolio
      1.1 MB
      PDF

      Primary side regulation controllers portfolio

Publications and Collaterals

    • Description Version Size Action
      Electric vehicle (EV) ecosystem 1.1
      1.28 MB
      PDF
      Power Management Guide 06.2019
      5.5 MB
      PDF

      Electric vehicle (EV) ecosystem

      Power Management Guide

Part Number Marketing Status Package Grade RoHS Compliance Grade Material Declaration**
UC3842BD1
Active
SO-8 Industrial Ecopack2
UC3842BD1013TR
Active
SO-8 Industrial Ecopack2
UC3842BN
Active
DIP-8 Industrial Ecopack2

UC3842BD1

Package:

SO-8

Material Declaration**:

PDF XML

Marketing Status

Active

Package

SO-8

Grade

Industrial

RoHS Compliance Grade

Ecopack2

UC3842BD1013TR

Package:

SO-8

Material Declaration**:

PDF XML

Marketing Status

Active

Package

SO-8

Grade

Industrial

RoHS Compliance Grade

Ecopack2

UC3842BN

Package:

DIP-8

Material Declaration**:

PDF XML

Marketing Status

Active

Package

DIP-8

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.