L4973

Active

3.5 A step down switching regulator

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Product overview

Description

The L4973 is a step down monolithic power switching regulator delivering 3.5A at fixed voltages of 3.3V or 5.1V and using a simple external divider output adjustable voltage up to 50V. Realized in BCD mixed technology, the device uses an internal power D-MOS transistor (with a typical RDS(on) of 0.15Ω) to obtain very high efficiency and very fast switching times. Switching frequency up to 300KHz are 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 40V cover the majority of the today applications. Features of this new generation of DC-DC converter includes pulse by pulse current limit, hiccup mode for output short circuit protection, voltage feed forward regulation, soft start, input/output synchronization, protection against feedback loop disconnection, inhibit for zero current consumption and thermal shutdown. Packages available are in plastic dual in line, DIP- 18 (12+3+3) for standard assembly, and SO20 (12+4+4) for SMD assembly.
  • All features

    • Inhibit for zero current consumption (100mA at VCC= 24V)
    • Input/output synchronization function
    • Thermal shutdown
    • Protection against feedback disconnection
    • Soft start function
    • Output over voltage protection
    • Internal current limiting (pulse by pulse and HICCUP mode)
    • Zero load current operation (min 1mA)
    • Up to 3.5A step down converter
    • 3.3V and 5.1V (±1%) fixed output, and adjustable outputs from: 0.5V to 50V (3.3 type)5.1V to 50V (5.1 type)
    • Operating input voltage from 8V to 55V
    • Voltage feed forward
    • Precise 5.1V (1.5%) reference voltage externally available
    • Frequency adjustable up to 300kHz

Circuit Diagram

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Quality and Reliability

Part Number Marketing Status Package Grade RoHS Compliance Grade Material Declaration**
L4973D3.3
Active
SO-20 Industrial Ecopack2
L4973D3.3-013TR
Active
SO-20 Industrial Ecopack1 (*)
L4973D5.1
Active
SO-20 Industrial Ecopack2
L4973D5.1-013TR
Active
SO-20 Industrial Ecopack2
L4973V3.3
Active
PDIP 18 Industrial Ecopack1
L4973V5.1
Active
PDIP 18 Industrial Ecopack1

L4973D3.3

Package:

SO-20

Material Declaration**:

PDF XML

Marketing Status

Active

Package

SO-20

Grade

Industrial

RoHS Compliance Grade

Ecopack2

L4973D3.3-013TR

Package:

SO-20

Material Declaration**:

PDF XML

Marketing Status

Active

Package

SO-20

Grade

Industrial

RoHS Compliance Grade

Ecopack1 (*)

L4973D5.1

Package:

SO-20

Material Declaration**:

Marketing Status

Active

Package

SO-20

Grade

Industrial

RoHS Compliance Grade

Ecopack2

L4973D5.1-013TR

Package:

SO-20

Material Declaration**:

Marketing Status

Active

Package

SO-20

Grade

Industrial

RoHS Compliance Grade

Ecopack2

L4973V3.3

Package:

PDIP 18

Material Declaration**:

PDF XML

Marketing Status

Active

Package

PDIP 18

Grade

Industrial

RoHS Compliance Grade

Ecopack1

L4973V5.1

Package:

PDIP 18

Material Declaration**:

PDF XML

Marketing Status

Active

Package

PDIP 18

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.

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.

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
L4973D3.3 Available at 4 distributors

Distributor availability ofL4973D3.3

Distributor Name
Region Stock Min. Order Third party link
DIGIKEY WORLDWIDE 957 1 Order Now
RS COMPONENTS EUROPE 258 1 Order Now
MOUSER WORLDWIDE 1160 1 Order Now
Farnell Element14 EUROPE 942 1 Order Now

Distributor reported inventory date: 2021-02-28

Distributor Name

DIGIKEY

Stock

957

Min.Order

1

Region

WORLDWIDE Order Now

RS COMPONENTS

Stock

258

Min.Order

1

Region

EUROPE Order Now

MOUSER

Stock

1160

Min.Order

1

Region

WORLDWIDE Order Now

Farnell Element14

Stock

942

Min.Order

1

Region

EUROPE Order Now

Distributor reported inventory date: 2021-02-28

Buy Direct
Active
EAR99 NEC Tube SO-20 - - MALAYSIA 1.811 / 1k
L4973D5.1-013TR Available at 3 distributors

Distributor availability ofL4973D5.1-013TR

Distributor Name
Region Stock Min. Order Third party link
DIGIKEY WORLDWIDE 810 1 Order Now
MOUSER WORLDWIDE 23 1 Order Now
ANGLIA Live EUROPE 23145 1 Order Now

Distributor reported inventory date: 2021-02-28

Distributor Name

DIGIKEY

Stock

810

Min.Order

1

Region

WORLDWIDE Order Now

MOUSER

Stock

23

Min.Order

1

Region

WORLDWIDE Order Now

ANGLIA Live

Stock

23145

Min.Order

1

Region

EUROPE Order Now

Distributor reported inventory date: 2021-02-28

Buy Direct
Active
EAR99 NEC Tape And Reel SO-20 - - MALAYSIA 1.861 / 1k
L4973V3.3 Available at 3 distributors

Distributor availability ofL4973V3.3

Distributor Name
Region Stock Min. Order Third party link
DIGIKEY WORLDWIDE 910 1 Order Now
MOUSER WORLDWIDE 727 1 Order Now
Farnell Element14 EUROPE 961 1 Order Now

Distributor reported inventory date: 2021-02-28

Distributor Name

DIGIKEY

Stock

910

Min.Order

1

Region

WORLDWIDE Order Now

MOUSER

Stock

727

Min.Order

1

Region

WORLDWIDE Order Now

Farnell Element14

Stock

961

Min.Order

1

Region

EUROPE Order Now

Distributor reported inventory date: 2021-02-28

Free Sample Buy Direct
Active
EAR99 NEC Tube PDIP 18 - - MALAYSIA 1.693 / 1k
L4973D3.3-013TR Available at 3 distributors

Distributor availability ofL4973D3.3-013TR

Distributor Name
Region Stock Min. Order Third party link
DIGIKEY WORLDWIDE 1976 1 Order Now
FUTURE WORLDWIDE 2000 1000 Order Now
MOUSER WORLDWIDE 314 1 Order Now

Distributor reported inventory date: 2021-02-28

Distributor Name

DIGIKEY

Stock

1976

Min.Order

1

Region

WORLDWIDE Order Now

FUTURE

Stock

2000

Min.Order

1000

Region

WORLDWIDE Order Now

MOUSER

Stock

314

Min.Order

1

Region

WORLDWIDE Order Now

Distributor reported inventory date: 2021-02-28

Buy Direct
Active
EAR99 NEC Tape And Reel SO-20 - - MALAYSIA 1.811 / 1k
L4973D5.1 Available at 4 distributors

Distributor availability ofL4973D5.1

Distributor Name
Region Stock Min. Order Third party link
RS COMPONENTS EUROPE 173 1 Order Now
MOUSER WORLDWIDE 661 1 Order Now
Farnell Element14 EUROPE 159 1 Order Now
ANGLIA Live EUROPE 307 1 Order Now

Distributor reported inventory date: 2021-02-28

Distributor Name

RS COMPONENTS

Stock

173

Min.Order

1

Region

EUROPE Order Now

MOUSER

Stock

661

Min.Order

1

Region

WORLDWIDE Order Now

Farnell Element14

Stock

159

Min.Order

1

Region

EUROPE Order Now

ANGLIA Live

Stock

307

Min.Order

1

Region

EUROPE Order Now

Distributor reported inventory date: 2021-02-28

Buy Direct
Active
EAR99 NEC Tube SO-20 - - MALAYSIA 1.861 / 1k
L4973V5.1 Available at 5 distributors

Distributor availability ofL4973V5.1

Distributor Name
Region Stock Min. Order Third party link
DIGIKEY WORLDWIDE 658 1 Order Now
RS COMPONENTS EUROPE 265 1 Order Now
Newark Element14 AMERICA 3 0 Order Now
MOUSER WORLDWIDE 1402 1 Order Now
ANGLIA Live EUROPE 560 20 Order Now

Distributor reported inventory date: 2021-02-28

Distributor Name

DIGIKEY

Stock

658

Min.Order

1

Region

WORLDWIDE Order Now

RS COMPONENTS

Stock

265

Min.Order

1

Region

EUROPE Order Now

Newark Element14

Stock

3

Min.Order

0

Region

AMERICA Order Now

MOUSER

Stock

1402

Min.Order

1

Region

WORLDWIDE Order Now

ANGLIA Live

Stock

560

Min.Order

20

Region

EUROPE Order Now

Distributor reported inventory date: 2021-02-28

Free Sample Buy Direct
Active
EAR99 NEC Tube PDIP 18 - - MALAYSIA 1.778 / 1k

L4973D3.3

Marketing Status

Active

ECCN (US)

EAR99

Budgetary Price (US$)*/Qty

1.811 / 1k

Distributor availability ofL4973D3.3

Distributor Name
Region Stock Min. Order Third party link
DIGIKEY WORLDWIDE 957 1 Order Now
RS COMPONENTS EUROPE 258 1 Order Now
MOUSER WORLDWIDE 1160 1 Order Now
Farnell Element14 EUROPE 942 1 Order Now

Distributor reported inventory date: 2021-02-28

Distributor Name

DIGIKEY

Stock

957

Min.Order

1

Region

WORLDWIDE Order Now

RS COMPONENTS

Stock

258

Min.Order

1

Region

EUROPE Order Now

MOUSER

Stock

1160

Min.Order

1

Region

WORLDWIDE Order Now

Farnell Element14

Stock

942

Min.Order

1

Region

EUROPE Order Now

Distributor reported inventory date: 2021-02-28

ECCN (EU)

NEC

Packing Type

Tube

Package

SO-20

Operating Temperature (°C)

(min)

-

(max)

-

Budgetary Price (US$)* / Qty

1.811 / 1k

Country of Origin

MALAYSIA

L4973D5.1-013TR

Marketing Status

Active

ECCN (US)

EAR99

Budgetary Price (US$)*/Qty

1.861 / 1k

Distributor availability ofL4973D5.1-013TR

Distributor Name
Region Stock Min. Order Third party link
DIGIKEY WORLDWIDE 810 1 Order Now
MOUSER WORLDWIDE 23 1 Order Now
ANGLIA Live EUROPE 23145 1 Order Now

Distributor reported inventory date: 2021-02-28

Distributor Name

DIGIKEY

Stock

810

Min.Order

1

Region

WORLDWIDE Order Now

MOUSER

Stock

23

Min.Order

1

Region

WORLDWIDE Order Now

ANGLIA Live

Stock

23145

Min.Order

1

Region

EUROPE Order Now

Distributor reported inventory date: 2021-02-28

ECCN (EU)

NEC

Packing Type

Tape And Reel

Package

SO-20

Operating Temperature (°C)

(min)

-

(max)

-

Budgetary Price (US$)* / Qty

1.861 / 1k

Country of Origin

MALAYSIA

L4973V3.3

Marketing Status

Active

ECCN (US)

EAR99

Budgetary Price (US$)*/Qty

1.693 / 1k

Distributor availability ofL4973V3.3

Distributor Name
Region Stock Min. Order Third party link
DIGIKEY WORLDWIDE 910 1 Order Now
MOUSER WORLDWIDE 727 1 Order Now
Farnell Element14 EUROPE 961 1 Order Now

Distributor reported inventory date: 2021-02-28

Distributor Name

DIGIKEY

Stock

910

Min.Order

1

Region

WORLDWIDE Order Now

MOUSER

Stock

727

Min.Order

1

Region

WORLDWIDE Order Now

Farnell Element14

Stock

961

Min.Order

1

Region

EUROPE Order Now

Distributor reported inventory date: 2021-02-28

ECCN (EU)

NEC

Packing Type

Tube

Package

PDIP 18

Operating Temperature (°C)

(min)

-

(max)

-

Budgetary Price (US$)* / Qty

1.693 / 1k

Country of Origin

MALAYSIA

L4973D3.3-013TR

Marketing Status

Active

ECCN (US)

EAR99

Budgetary Price (US$)*/Qty

1.811 / 1k

Distributor availability ofL4973D3.3-013TR

Distributor Name
Region Stock Min. Order Third party link
DIGIKEY WORLDWIDE 1976 1 Order Now
FUTURE WORLDWIDE 2000 1000 Order Now
MOUSER WORLDWIDE 314 1 Order Now

Distributor reported inventory date: 2021-02-28

Distributor Name

DIGIKEY

Stock

1976

Min.Order

1

Region

WORLDWIDE Order Now

FUTURE

Stock

2000

Min.Order

1000

Region

WORLDWIDE Order Now

MOUSER

Stock

314

Min.Order

1

Region

WORLDWIDE Order Now

Distributor reported inventory date: 2021-02-28

ECCN (EU)

NEC

Packing Type

Tape And Reel

Package

SO-20

Operating Temperature (°C)

(min)

-

(max)

-

Budgetary Price (US$)* / Qty

1.811 / 1k

Country of Origin

MALAYSIA

L4973D5.1

Marketing Status

Active

ECCN (US)

EAR99

Budgetary Price (US$)*/Qty

1.861 / 1k

Distributor availability ofL4973D5.1

Distributor Name
Region Stock Min. Order Third party link
RS COMPONENTS EUROPE 173 1 Order Now
MOUSER WORLDWIDE 661 1 Order Now
Farnell Element14 EUROPE 159 1 Order Now
ANGLIA Live EUROPE 307 1 Order Now

Distributor reported inventory date: 2021-02-28

Distributor Name

RS COMPONENTS

Stock

173

Min.Order

1

Region

EUROPE Order Now

MOUSER

Stock

661

Min.Order

1

Region

WORLDWIDE Order Now

Farnell Element14

Stock

159

Min.Order

1

Region

EUROPE Order Now

ANGLIA Live

Stock

307

Min.Order

1

Region

EUROPE Order Now

Distributor reported inventory date: 2021-02-28

ECCN (EU)

NEC

Packing Type

Tube

Package

SO-20

Operating Temperature (°C)

(min)

-

(max)

-

Budgetary Price (US$)* / Qty

1.861 / 1k

Country of Origin

MALAYSIA

L4973V5.1

Marketing Status

Active

ECCN (US)

EAR99

Budgetary Price (US$)*/Qty

1.778 / 1k

Distributor availability ofL4973V5.1

Distributor Name
Region Stock Min. Order Third party link
DIGIKEY WORLDWIDE 658 1 Order Now
RS COMPONENTS EUROPE 265 1 Order Now
Newark Element14 AMERICA 3 0 Order Now
MOUSER WORLDWIDE 1402 1 Order Now
ANGLIA Live EUROPE 560 20 Order Now

Distributor reported inventory date: 2021-02-28

Distributor Name

DIGIKEY

Stock

658

Min.Order

1

Region

WORLDWIDE Order Now

RS COMPONENTS

Stock

265

Min.Order

1

Region

EUROPE Order Now

Newark Element14

Stock

3

Min.Order

0

Region

AMERICA Order Now

MOUSER

Stock

1402

Min.Order

1

Region

WORLDWIDE Order Now

ANGLIA Live

Stock

560

Min.Order

20

Region

EUROPE Order Now

Distributor reported inventory date: 2021-02-28

ECCN (EU)

NEC

Packing Type

Tube

Package

PDIP 18

Operating Temperature (°C)

(min)

-

(max)

-

Budgetary Price (US$)* / Qty

1.778 / 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