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  • The ST1S40 is an internally compensated 850 kHz fixed-frequency PWM synchronous step-down regulator. ST1S40 operates from 4.0 V to 18 V input, while it regulates an output voltage as low as 0.8 V and up to VIN.

    The ST1S40 integrates a 95 mΩ high side switch and 69 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 ST1S40 is available in VFQFPN 4 mm x 4 mm 8 lead package, HSOP-8 and standard SO-8 package.

    Key Features

    • 3 A DC output current
    • 4.0 V to 18 V input voltage
    • Output voltage adjustable from 0.8 V
    • 850 kHz switching frequency
    • Internal soft-start
    • Integrated 95 mΩ and 69 mΩ Power MOSFETs
    • All ceramic capacitor
    • Enable
    • Cycle-by-cycle current limiting
    • Current fold back short-circuit protection
    • VFQFPN4x4-8L, HSOP-8, and SO-8 and packages

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    • Part number
      Status
      Description
      Type
      Supplier

      STEVAL-ISA084V1

      Active

      4 A peak, 800 kHz fixed-frequency PWM synchronous step-down demonstration board with enable on/off based on the ST1S40

      PSU and Converter Solution Eval Boards --
      STEVAL-ISA084V1

      Description:

      4 A peak, 800 kHz fixed-frequency PWM synchronous step-down demonstration board with enable on/off based on the ST1S40

CAD/EDA Symbols, Footprints and Models

Quality and Reliability

Part Number Marketing Status Package Grade RoHS Compliance Grade Material Declaration**
ST1S40IDR
Active
SO-8 Industrial Ecopack2
ST1S40IPHR
Active
PowerSO-8 Industrial Ecopack2
ST1S40IPUR
Active
DFN8 4x4 Industrial Ecopack2

ST1S40IDR

Package:

SO-8

Material Declaration**:

PDF XML

Marketing Status

Active

Package

SO-8

Grade

Industrial

RoHS Compliance Grade

Ecopack2

ST1S40IPHR

Package:

PowerSO-8

Material Declaration**:

PDF XML

Marketing Status

Active

Package

PowerSO-8

Grade

Industrial

RoHS Compliance Grade

Ecopack2

ST1S40IPUR

Package:

DFN8 4x4

Material Declaration**:

PDF XML

Marketing Status

Active

Package

DFN8 4x4

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

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

Sample & Buy

Part Number
Order from Distributors
Order from ST
Marketing Status
ECCN (US)
ECCN (EU)
Packing Type
Package
Temperature (°C) Country of Origin
Budgetary Price (US$)*/Qty
min
max
ST1S40IPHR Available at 7 distributors

Distributor availability ofST1S40IPHR

Distributor Name
Region Stock Min. Order Third party link
DIGIKEY WORLDWIDE 14293 1 Order Now
RS COMPONENTS EUROPE 2100 1 Order Now
AVNET AMERICA 5000 0 Order Now
ARROW EUROPE 12500 0 Order Now
Newark Element14 AMERICA 600 0 Order Now
MOUSER WORLDWIDE 6809 1 Order Now
Farnell Element14 EUROPE 1464 1 Order Now

Distributor reported inventory date: 2020-10-23

Distributor Name

DIGIKEY

Stock

14293

Min.Order

1

Region

WORLDWIDE Order Now

RS COMPONENTS

Stock

2100

Min.Order

1

Region

EUROPE Order Now

AVNET

Stock

5000

Min.Order

0

Region

AMERICA Order Now

ARROW

Stock

12500

Min.Order

0

Region

EUROPE Order Now

Newark Element14

Stock

600

Min.Order

0

Region

AMERICA Order Now

MOUSER

Stock

6809

Min.Order

1

Region

WORLDWIDE Order Now

Farnell Element14

Stock

1464

Min.Order

1

Region

EUROPE Order Now

Distributor reported inventory date: 2020-10-23

Free Sample Buy Direct
Active
EAR99 NEC Tape And Reel PowerSO-8 - - PHILIPPINES 0.76 / 1k
ST1S40IDR Available at 6 distributors

Distributor availability ofST1S40IDR

Distributor Name
Region Stock Min. Order Third party link
DIGIKEY WORLDWIDE 16249 1 Order Now
COMPEL EUROPE 3541 1 Order Now
ARROW EUROPE 5000 0 Order Now
Newark Element14 AMERICA 277 0 Order Now
MOUSER WORLDWIDE 3014 1 Order Now
Farnell Element14 EUROPE 1794 1 Order Now

Distributor reported inventory date: 2020-10-23

Distributor Name

DIGIKEY

Stock

16249

Min.Order

1

Region

WORLDWIDE Order Now

COMPEL

Stock

3541

Min.Order

1

Region

EUROPE Order Now

ARROW

Stock

5000

Min.Order

0

Region

EUROPE Order Now

Newark Element14

Stock

277

Min.Order

0

Region

AMERICA Order Now

MOUSER

Stock

3014

Min.Order

1

Region

WORLDWIDE Order Now

Farnell Element14

Stock

1794

Min.Order

1

Region

EUROPE Order Now

Distributor reported inventory date: 2020-10-23

Free Sample Buy Direct
Active
EAR99 NEC Tape And Reel SO-8 - - CHINA 0.68 / 1k
ST1S40IPUR Available at 5 distributors

Distributor availability ofST1S40IPUR

Distributor Name
Region Stock Min. Order Third party link
DIGIKEY WORLDWIDE 1091 1 Order Now
FUTURE WORLDWIDE 9000 4500 Order Now
ARROW EUROPE 13500 0 Order Now
ARROW AMERICA 4500 4500 Order Now
MOUSER WORLDWIDE 3991 1 Order Now

Distributor reported inventory date: 2020-10-23

Distributor Name

DIGIKEY

Stock

1091

Min.Order

1

Region

WORLDWIDE Order Now

FUTURE

Stock

9000

Min.Order

4500

Region

WORLDWIDE Order Now

ARROW

Stock

13500

Min.Order

0

Region

EUROPE Order Now

ARROW

Stock

4500

Min.Order

4500

Region

AMERICA Order Now

MOUSER

Stock

3991

Min.Order

1

Region

WORLDWIDE Order Now

Distributor reported inventory date: 2020-10-23

Free Sample Buy Direct
Active
EAR99 NEC Tape And Reel DFN8 4x4 - - MALAYSIA 0.74 / 1k

ST1S40IPHR

Marketing Status

Active

ECCN (US)

EAR99

Budgetary Price (US$)*/Qty

0.76 / 1k

Distributor availability ofST1S40IPHR

Distributor Name
Region Stock Min. Order Third party link
DIGIKEY WORLDWIDE 14293 1 Order Now
RS COMPONENTS EUROPE 2100 1 Order Now
AVNET AMERICA 5000 0 Order Now
ARROW EUROPE 12500 0 Order Now
Newark Element14 AMERICA 600 0 Order Now
MOUSER WORLDWIDE 6809 1 Order Now
Farnell Element14 EUROPE 1464 1 Order Now

Distributor reported inventory date: 2020-10-23

Distributor Name

DIGIKEY

Stock

14293

Min.Order

1

Region

WORLDWIDE Order Now

RS COMPONENTS

Stock

2100

Min.Order

1

Region

EUROPE Order Now

AVNET

Stock

5000

Min.Order

0

Region

AMERICA Order Now

ARROW

Stock

12500

Min.Order

0

Region

EUROPE Order Now

Newark Element14

Stock

600

Min.Order

0

Region

AMERICA Order Now

MOUSER

Stock

6809

Min.Order

1

Region

WORLDWIDE Order Now

Farnell Element14

Stock

1464

Min.Order

1

Region

EUROPE Order Now

Distributor reported inventory date: 2020-10-23

ECCN (EU)

NEC

Packing Type

Tape And Reel

Package

PowerSO-8

Operating Temperature (°C)

(min)

-

(max)

-

Budgetary Price (US$)* / Qty

0.76 / 1k

Country of Origin

PHILIPPINES

ST1S40IDR

Marketing Status

Active

ECCN (US)

EAR99

Budgetary Price (US$)*/Qty

0.68 / 1k

Distributor availability ofST1S40IDR

Distributor Name
Region Stock Min. Order Third party link
DIGIKEY WORLDWIDE 16249 1 Order Now
COMPEL EUROPE 3541 1 Order Now
ARROW EUROPE 5000 0 Order Now
Newark Element14 AMERICA 277 0 Order Now
MOUSER WORLDWIDE 3014 1 Order Now
Farnell Element14 EUROPE 1794 1 Order Now

Distributor reported inventory date: 2020-10-23

Distributor Name

DIGIKEY

Stock

16249

Min.Order

1

Region

WORLDWIDE Order Now

COMPEL

Stock

3541

Min.Order

1

Region

EUROPE Order Now

ARROW

Stock

5000

Min.Order

0

Region

EUROPE Order Now

Newark Element14

Stock

277

Min.Order

0

Region

AMERICA Order Now

MOUSER

Stock

3014

Min.Order

1

Region

WORLDWIDE Order Now

Farnell Element14

Stock

1794

Min.Order

1

Region

EUROPE Order Now

Distributor reported inventory date: 2020-10-23

ECCN (EU)

NEC

Packing Type

Tape And Reel

Package

SO-8

Operating Temperature (°C)

(min)

-

(max)

-

Budgetary Price (US$)* / Qty

0.68 / 1k

Country of Origin

CHINA

ST1S40IPUR

Marketing Status

Active

ECCN (US)

EAR99

Budgetary Price (US$)*/Qty

0.74 / 1k

Distributor availability ofST1S40IPUR

Distributor Name
Region Stock Min. Order Third party link
DIGIKEY WORLDWIDE 1091 1 Order Now
FUTURE WORLDWIDE 9000 4500 Order Now
ARROW EUROPE 13500 0 Order Now
ARROW AMERICA 4500 4500 Order Now
MOUSER WORLDWIDE 3991 1 Order Now

Distributor reported inventory date: 2020-10-23

Distributor Name

DIGIKEY

Stock

1091

Min.Order

1

Region

WORLDWIDE Order Now

FUTURE

Stock

9000

Min.Order

4500

Region

WORLDWIDE Order Now

ARROW

Stock

13500

Min.Order

0

Region

EUROPE Order Now

ARROW

Stock

4500

Min.Order

4500

Region

AMERICA Order Now

MOUSER

Stock

3991

Min.Order

1

Region

WORLDWIDE Order Now

Distributor reported inventory date: 2020-10-23

ECCN (EU)

NEC

Packing Type

Tape And Reel

Package

DFN8 4x4

Operating Temperature (°C)

(min)

-

(max)

-

Budgetary Price (US$)* / Qty

0.74 / 1k

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