3 A step-down switching regulator

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  • The L7981 device is a step-down switching regulator with a 3.7 A (minimum) current limited embedded Power MOSFET, so it is able to deliver up to 3 A current to the load depending on the application conditions.

    The input voltage can range from 4.5 V to 28 V, while the output voltage can be set starting from 0.6 V to VIN.
    Requiring a minimum set of external components, the device includes an internal 250 kHz switching frequency oscillator that can be externally adjusted up to 1 MHz.
    The QFN and the HSOP packages with exposed pad allow reducing the RthJAdown to 60°C/W and 40°C/W respectively.

    Key Features

    • 3 A DC output current
    • 4.5 V to 28 V input voltage
    • Output voltage adjustable from 0.6 V
    • 250 kHz switching frequency, programmable up to 1 MHz
    • Internal soft-start and enable
    • Low dropout operation: 100% duty cycle
    • Voltage feed-forward
    • Zero load current operation
    • Overcurrent and thermal protection
    • VFQFPN 3 x 3 - 8L and HSOP8 package

Circuit Diagram

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Part Number
Package
Packing Type
Marketing Status
Budgetary Price (US$)*
Quantity
ECCN (US)
Country of Origin
Order from Distributors
Order from ST
L7981A PowerSO-8 Tube
Active
0.746 10000 EAR99 CHINA Check Availability

Distributor availability ofL7981A

Distributor Name
Region Stock Min. Order Third party link
MOUSER WORLDWIDE 1246 1 Order Now
Farnell Element14 EUROPE 198 1 Order Now

Distributor reported inventory date: 2019-12-10

Distributor Name

MOUSER

Stock

1246

Min.Order

1

Region

WORLDWIDE Order Now

Farnell Element14

Stock

198

Min.Order

1

Region

EUROPE Order Now

Distributor reported inventory date: 2019-12-10

Buy now
L7981TR DFN8 3x3 Tape And Reel
Active
0.719 10000 EAR99 PHILIPPINES Check Availability

Distributor availability ofL7981TR

Distributor Name
Region Stock Min. Order Third party link
DIGIKEY WORLDWIDE 4000 1 Order Now
Newark Element14 AMERICA 2740 0 Order Now
MOUSER WORLDWIDE 3630 1 Order Now
Farnell Element14 EUROPE 2620 1 Order Now

Distributor reported inventory date: 2019-12-10

Distributor Name

DIGIKEY

Stock

4000

Min.Order

1

Region

WORLDWIDE Order Now

Newark Element14

Stock

2740

Min.Order

0

Region

AMERICA Order Now

MOUSER

Stock

3630

Min.Order

1

Region

WORLDWIDE Order Now

Farnell Element14

Stock

2620

Min.Order

1

Region

EUROPE Order Now

Distributor reported inventory date: 2019-12-10

Get sample
L7981ATR PowerSO-8 Tape And Reel
Active
0.746 10000 EAR99 CHINA Check Availability

Distributor availability ofL7981ATR

Distributor Name
Region Stock Min. Order Third party link
DIGIKEY WORLDWIDE 12374 1 Order Now
FUTURE WORLDWIDE 2500 2500 Order Now
Newark Element14 AMERICA 261 0 Order Now
MOUSER WORLDWIDE 8965 1 Order Now
Farnell Element14 EUROPE 2926 1 Order Now

Distributor reported inventory date: 2019-12-10

Distributor Name

DIGIKEY

Stock

12374

Min.Order

1

Region

WORLDWIDE Order Now

FUTURE

Stock

2500

Min.Order

2500

Region

WORLDWIDE Order Now

Newark Element14

Stock

261

Min.Order

0

Region

AMERICA Order Now

MOUSER

Stock

8965

Min.Order

1

Region

WORLDWIDE Order Now

Farnell Element14

Stock

2926

Min.Order

1

Region

EUROPE Order Now

Distributor reported inventory date: 2019-12-10

Get sample

L7981A

Package

PowerSO-8

Packing Type

Tube

Unit Price (US$)

0.746*

Distributor availability ofL7981A

Distributor Name
Region Stock Min. Order Third party link
MOUSER WORLDWIDE 1246 1 Order Now
Farnell Element14 EUROPE 198 1 Order Now

Distributor reported inventory date: 2019-12-10

Distributor Name

MOUSER

Stock

1246

Min.Order

1

Region

WORLDWIDE Order Now

Farnell Element14

Stock

198

Min.Order

1

Region

EUROPE Order Now

Distributor reported inventory date: 2019-12-10

Marketing Status

Active

Unit Price (US$)

0.746

Quantity

10000

ECCN (US)

EAR99

Country of Origin

CHINA

L7981TR

Package

DFN8 3x3

Packing Type

Tape And Reel

Unit Price (US$)

0.719*

Distributor availability ofL7981TR

Distributor Name
Region Stock Min. Order Third party link
DIGIKEY WORLDWIDE 4000 1 Order Now
Newark Element14 AMERICA 2740 0 Order Now
MOUSER WORLDWIDE 3630 1 Order Now
Farnell Element14 EUROPE 2620 1 Order Now

Distributor reported inventory date: 2019-12-10

Distributor Name

DIGIKEY

Stock

4000

Min.Order

1

Region

WORLDWIDE Order Now

Newark Element14

Stock

2740

Min.Order

0

Region

AMERICA Order Now

MOUSER

Stock

3630

Min.Order

1

Region

WORLDWIDE Order Now

Farnell Element14

Stock

2620

Min.Order

1

Region

EUROPE Order Now

Distributor reported inventory date: 2019-12-10

Marketing Status

Active

Unit Price (US$)

0.719

Quantity

10000

ECCN (US)

EAR99

Country of Origin

PHILIPPINES

L7981ATR

Package

PowerSO-8

Packing Type

Tape And Reel

Unit Price (US$)

0.746*

Distributor availability ofL7981ATR

Distributor Name
Region Stock Min. Order Third party link
DIGIKEY WORLDWIDE 12374 1 Order Now
FUTURE WORLDWIDE 2500 2500 Order Now
Newark Element14 AMERICA 261 0 Order Now
MOUSER WORLDWIDE 8965 1 Order Now
Farnell Element14 EUROPE 2926 1 Order Now

Distributor reported inventory date: 2019-12-10

Distributor Name

DIGIKEY

Stock

12374

Min.Order

1

Region

WORLDWIDE Order Now

FUTURE

Stock

2500

Min.Order

2500

Region

WORLDWIDE Order Now

Newark Element14

Stock

261

Min.Order

0

Region

AMERICA Order Now

MOUSER

Stock

8965

Min.Order

1

Region

WORLDWIDE Order Now

Farnell Element14

Stock

2926

Min.Order

1

Region

EUROPE Order Now

Distributor reported inventory date: 2019-12-10

Marketing Status

Active

Unit Price (US$)

0.746

Quantity

10000

ECCN (US)

EAR99

Country of Origin

CHINA

(*) 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**
L7981A
Active
PowerSO-8 Industrial Ecopack2
L7981ATR
Active
PowerSO-8 Industrial Ecopack2
L7981TR
Active
DFN8 3x3 Industrial Ecopack2

L7981A

Package:

PowerSO-8

Material Declaration**:

PDF XML

Marketing Status

Active

Package

PowerSO-8

Grade

Industrial

RoHS Compliance Grade

Ecopack2

L7981ATR

Package:

PowerSO-8

Material Declaration**:

PDF XML

Marketing Status

Active

Package

PowerSO-8

Grade

Industrial

RoHS Compliance Grade

Ecopack2

L7981TR

Package:

DFN8 3x3

Material Declaration**:

Marketing Status

Active

Package

DFN8 3x3

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.

eDesignSuite

Converter

Input

V This option is required. And must be less than or equal to Volt. Max [V]
V This option is required. And must be greater than or equal to Volt. Min [V]

Output Power

V This option is required and must be a number.
A This option is required and must be a number.

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