3 A DC step-down switching regulator

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  • The ST1S31 device is an internally compensated 1.5 MHz fixed-frequency PWM synchronous step-down regulator. The ST1S31 operates from 2.8 V to 5.5 V input, while it regulates an output voltage as low as 0.8 V and up to VIN.

    The ST1S31 integrates a 60 mΩ high-side switch and a 45 mΩ synchronous rectifier allowing very high efficiency with very low output voltages.
    The peak current mode control with internal compensation delivers a very compact solution with a minimum component count.
    The ST1S31 device is available in 3 mm x 3 mm, 8 lead VFDFPN and SO8 packages.

    Key Features

    • 3 A DC output current
    • 2.8 V to 5.5 V input voltage
    • Output voltage adjustable from 0.8 V
    • 1.5 MHz switching frequency
    • Internal soft-start and enable
    • Integrated 60 mΩ and 45 mΩ power MOSFETs
    • All ceramic capacitor
    • Power Good (POR)
    • Cycle-by-cycle current limiting
    • Current foldback short-circuit protection
    • VFDFPN 3 x 3 - 8L, SO8 packages

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Part Number
Package
Packing Type
Marketing Status
Budgetary Price (US$)*
Quantity
ECCN (US)
Country of Origin
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Order from ST
ST1S31D-R SO-8 Tape And Reel
Active
0.471 10000 EAR99 CHINA Check Availability

Distributor availability ofST1S31D-R

Distributor Name
Region Stock Min. Order Third party link
DIGIKEY WORLDWIDE 2475 1 Order Now
RS COMPONENTS EUROPE 45 1 Order Now
MOUSER WORLDWIDE 4903 1 Order Now

Distributor reported inventory date: 2019-12-08

Distributor Name

DIGIKEY

Stock

2475

Min.Order

1

Region

WORLDWIDE Order Now

RS COMPONENTS

Stock

45

Min.Order

1

Region

EUROPE Order Now

MOUSER

Stock

4903

Min.Order

1

Region

WORLDWIDE Order Now

Distributor reported inventory date: 2019-12-08

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ST1S31PUR VFDFPN 8 3x3x1.0 Tape And Reel
Active
0.535 10000 EAR99 MALAYSIA Check Availability

Distributor availability ofST1S31PUR

Distributor Name
Region Stock Min. Order Third party link
DIGIKEY WORLDWIDE 2840 1 Order Now
RS COMPONENTS EUROPE 790 1 Order Now
MOUSER WORLDWIDE 3191 1 Order Now
Farnell Element14 EUROPE 1004 1 Order Now

Distributor reported inventory date: 2019-12-08

Distributor Name

DIGIKEY

Stock

2840

Min.Order

1

Region

WORLDWIDE Order Now

RS COMPONENTS

Stock

790

Min.Order

1

Region

EUROPE Order Now

MOUSER

Stock

3191

Min.Order

1

Region

WORLDWIDE Order Now

Farnell Element14

Stock

1004

Min.Order

1

Region

EUROPE Order Now

Distributor reported inventory date: 2019-12-08

Get sample

ST1S31D-R

Package

SO-8

Packing Type

Tape And Reel

Unit Price (US$)

0.471*

Distributor availability ofST1S31D-R

Distributor Name
Region Stock Min. Order Third party link
DIGIKEY WORLDWIDE 2475 1 Order Now
RS COMPONENTS EUROPE 45 1 Order Now
MOUSER WORLDWIDE 4903 1 Order Now

Distributor reported inventory date: 2019-12-08

Distributor Name

DIGIKEY

Stock

2475

Min.Order

1

Region

WORLDWIDE Order Now

RS COMPONENTS

Stock

45

Min.Order

1

Region

EUROPE Order Now

MOUSER

Stock

4903

Min.Order

1

Region

WORLDWIDE Order Now

Distributor reported inventory date: 2019-12-08

Marketing Status

Active

Unit Price (US$)

0.471

Quantity

10000

ECCN (US)

EAR99

Country of Origin

CHINA

ST1S31PUR

Package

VFDFPN 8 3x3x1.0

Packing Type

Tape And Reel

Unit Price (US$)

0.535*

Distributor availability ofST1S31PUR

Distributor Name
Region Stock Min. Order Third party link
DIGIKEY WORLDWIDE 2840 1 Order Now
RS COMPONENTS EUROPE 790 1 Order Now
MOUSER WORLDWIDE 3191 1 Order Now
Farnell Element14 EUROPE 1004 1 Order Now

Distributor reported inventory date: 2019-12-08

Distributor Name

DIGIKEY

Stock

2840

Min.Order

1

Region

WORLDWIDE Order Now

RS COMPONENTS

Stock

790

Min.Order

1

Region

EUROPE Order Now

MOUSER

Stock

3191

Min.Order

1

Region

WORLDWIDE Order Now

Farnell Element14

Stock

1004

Min.Order

1

Region

EUROPE Order Now

Distributor reported inventory date: 2019-12-08

Marketing Status

Active

Unit Price (US$)

0.535

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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00 Files selected for download

Technical Documentation

    • Description Version Size Action
      DS8977
      3 A DC step-down switching regulator
      5.0
      1.5 MB
      PDF
      DS8977

      3 A DC step-down switching regulator

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      Switching Converters (DC-DC) – Quick Reference Guide 1.0
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      Electric vehicle (EV) ecosystem

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Part Number Marketing Status Package Grade RoHS Compliance Grade Material Declaration**
ST1S31D-R
Active
SO-8 Industrial Ecopack2
ST1S31PUR
Active
VFDFPN 8 3x3x1.0 Industrial Ecopack2

ST1S31D-R

Package:

SO-8

Material Declaration**:

Marketing Status

Active

Package

SO-8

Grade

Industrial

RoHS Compliance Grade

Ecopack2

ST1S31PUR

Package:

VFDFPN 8 3x3x1.0

Material Declaration**:

PDF XML

Marketing Status

Active

Package

VFDFPN 8 3x3x1.0

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.

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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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