2A Step down switching regulator

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  • The L4978 is a step down monolithic power switching regulator delivering 2A at a voltage between 3.3V and 50V (selected by a simple external divider). Realized in BCD mixed technology, the device uses an internal power D-MOS transistor (with a typical Rdson of 0.25Ω) to obtain very high efficency and high switching speed.

    A switching frequency up to 300KHz is achievable (the maximum power dissipation of the packages must be observed). A wide input voltage range between 8V to 55V and output voltages regulated from 3.3V to 50V cover the majority of today’s applications. Features of this new generations of DC-DC converter include pulse-by-pulse current limit, hiccup mode for short circuit protection, voltage feedforward regulation, soft-start, protection against feedback loop disconnection, inhibit for zero current consumption and thermal shutdown.
    The device is available in plastic dual in line, DIP-8 for standard assembly, and SO16W for SMD assembly.

    Key Features

    • PROTECTION AGAINST FEEDBACK DISCONNECTION
    • INHIBIT FOR ZERO CURRENT CONSUMPTION
    • SOFT START FUNCTION
    • THERMAL SHUTDOWN
    • ZERO LOAD CURRENT OPERATION
    • VOLTAGE FEEDFORWARD
    • UP TO 2A STEP DOWN CONVERTER
    • PRECISE 3.3V (±1%) INTERNAL REFERENCE VOLTAGE
    • OPERATING INPUT VOLTAGE FROM 8V TO 55V
    • SWITCHING FREQUENCY ADJUSTABLE UP TO 300KHz
    • INTERNAL CURRENT LIMITING (PULSE-BYPULSE AND HICCUP MODE)
    • OUTPUT VOLTAGE ADJUSTABLE FROM 3.3V TO 50V

Circuit Diagram

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Part Number
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Quantity
ECCN (US)
Country of Origin
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L4978D013TR SO-16W Tape And Reel
Active
1.389 10000 EAR99 MALAYSIA Check Availability

Distributor availability ofL4978D013TR

Distributor Name
Region Stock Min. Order Third party link
DIGIKEY WORLDWIDE 2413 1 Order Now
MOUSER WORLDWIDE 2920 1 Order Now

Distributor reported inventory date: 2019-11-21

Distributor Name

DIGIKEY

Stock

2413

Min.Order

1

Region

WORLDWIDE Order Now

MOUSER

Stock

2920

Min.Order

1

Region

WORLDWIDE Order Now

Distributor reported inventory date: 2019-11-21

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L4978 DIP-8 Tube
Active
1.389 10000 EAR99 MALAYSIA Check Availability

Distributor availability ofL4978

Distributor Name
Region Stock Min. Order Third party link
DIGIKEY WORLDWIDE 842 1 Order Now
FUTURE WORLDWIDE 595 1 Order Now
ARROW EUROPE 100 0 Order Now
MOUSER WORLDWIDE 933 1 Order Now
Farnell Element14 EUROPE 982 1 Order Now

Distributor reported inventory date: 2019-11-21

Distributor Name

DIGIKEY

Stock

842

Min.Order

1

Region

WORLDWIDE Order Now

FUTURE

Stock

595

Min.Order

1

Region

WORLDWIDE Order Now

ARROW

Stock

100

Min.Order

0

Region

EUROPE Order Now

MOUSER

Stock

933

Min.Order

1

Region

WORLDWIDE Order Now

Farnell Element14

Stock

982

Min.Order

1

Region

EUROPE Order Now

Distributor reported inventory date: 2019-11-21

Get sample
L4978D SO-16W Tube
Active
1.389 10000 EAR99 MALAYSIA Check Availability

Distributor availability ofL4978D

Distributor Name
Region Stock Min. Order Third party link
RS COMPONENTS EUROPE 844 1 Order Now
ARROW AMERICA 9 1225 Order Now
MOUSER WORLDWIDE 943 1 Order Now
Farnell Element14 EUROPE 688 1 Order Now

Distributor reported inventory date: 2019-11-21

Distributor Name

RS COMPONENTS

Stock

844

Min.Order

1

Region

EUROPE Order Now

ARROW

Stock

9

Min.Order

1225

Region

AMERICA Order Now

MOUSER

Stock

943

Min.Order

1

Region

WORLDWIDE Order Now

Farnell Element14

Stock

688

Min.Order

1

Region

EUROPE Order Now

Distributor reported inventory date: 2019-11-21

Buy now

L4978D013TR

Package

SO-16W

Packing Type

Tape And Reel

Unit Price (US$)

1.389*

Distributor availability ofL4978D013TR

Distributor Name
Region Stock Min. Order Third party link
DIGIKEY WORLDWIDE 2413 1 Order Now
MOUSER WORLDWIDE 2920 1 Order Now

Distributor reported inventory date: 2019-11-21

Distributor Name

DIGIKEY

Stock

2413

Min.Order

1

Region

WORLDWIDE Order Now

MOUSER

Stock

2920

Min.Order

1

Region

WORLDWIDE Order Now

Distributor reported inventory date: 2019-11-21

Marketing Status

Active

Unit Price (US$)

1.389

Quantity

10000

ECCN (US)

EAR99

Country of Origin

MALAYSIA

L4978

Package

DIP-8

Packing Type

Tube

Unit Price (US$)

1.389*

Distributor availability ofL4978

Distributor Name
Region Stock Min. Order Third party link
DIGIKEY WORLDWIDE 842 1 Order Now
FUTURE WORLDWIDE 595 1 Order Now
ARROW EUROPE 100 0 Order Now
MOUSER WORLDWIDE 933 1 Order Now
Farnell Element14 EUROPE 982 1 Order Now

Distributor reported inventory date: 2019-11-21

Distributor Name

DIGIKEY

Stock

842

Min.Order

1

Region

WORLDWIDE Order Now

FUTURE

Stock

595

Min.Order

1

Region

WORLDWIDE Order Now

ARROW

Stock

100

Min.Order

0

Region

EUROPE Order Now

MOUSER

Stock

933

Min.Order

1

Region

WORLDWIDE Order Now

Farnell Element14

Stock

982

Min.Order

1

Region

EUROPE Order Now

Distributor reported inventory date: 2019-11-21

Marketing Status

Active

Unit Price (US$)

1.389

Quantity

10000

ECCN (US)

EAR99

Country of Origin

MALAYSIA

L4978D

Package

SO-16W

Packing Type

Tube

Unit Price (US$)

1.389*

Distributor availability ofL4978D

Distributor Name
Region Stock Min. Order Third party link
RS COMPONENTS EUROPE 844 1 Order Now
ARROW AMERICA 9 1225 Order Now
MOUSER WORLDWIDE 943 1 Order Now
Farnell Element14 EUROPE 688 1 Order Now

Distributor reported inventory date: 2019-11-21

Distributor Name

RS COMPONENTS

Stock

844

Min.Order

1

Region

EUROPE Order Now

ARROW

Stock

9

Min.Order

1225

Region

AMERICA Order Now

MOUSER

Stock

943

Min.Order

1

Region

WORLDWIDE Order Now

Farnell Element14

Stock

688

Min.Order

1

Region

EUROPE Order Now

Distributor reported inventory date: 2019-11-21

Marketing Status

Active

Unit Price (US$)

1.389

Quantity

10000

ECCN (US)

EAR99

Country of Origin

MALAYSIA

(*) 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

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Part Number Marketing Status Package Grade RoHS Compliance Grade Material Declaration**
L4978
Active
DIP-8 Industrial Ecopack2 (**)
L4978D
Active
SO-16W Industrial Ecopack1
L4978D013TR
Active
SO-16W Industrial Ecopack1

L4978

Package:

DIP-8

Material Declaration**:

Marketing Status

Active

Package

DIP-8

Grade

Industrial

RoHS Compliance Grade

Ecopack2 (**)

L4978D

Package:

SO-16W

Material Declaration**:

PDF XML

Marketing Status

Active

Package

SO-16W

Grade

Industrial

RoHS Compliance Grade

Ecopack1

L4978D013TR

Package:

SO-16W

Material Declaration**:

PDF XML

Marketing Status

Active

Package

SO-16W

Grade

Industrial

RoHS Compliance Grade

Ecopack1

(**) 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.

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