7 A switching regulator

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  • The L4977A is a stepdown monolithic power switching regulator delivering 7A at a voltage variable from 5.1 to 40V.

    Realized with BCD mixed technology, the device uses a DMOS output transistor to obtain very high efficiency and very fast switching times. Features of the L4977A include reset and power fail for microprocessors, feed forward line regulation, soft start, limiting current and thermal protection. The device is mounted in a 15-lead multiwatt plastic power package and requires few external components. Efficient operation at switching frequencies up to 500KHz allows reduction in the size and cost of external filter components.

    Key Features

    • UNDER VOLTAGE LOCK OUT WITH HYSTERETIC TURN-ON
    • INPUT/OUTPUT SYNC PIN
    • VERY HIGH EFFICIENCY
    • PWM LATCH FOR SINGLE PULSE PER PERIOD
    • THERMAL SHUTDOWN
    • SWITCHING FREQUENCY UP TO 500KHz
    • CONTINUOUS MODE OPERATION
    • RESET AND POWER FAIL FUNCTIONS
    • PRECISE 5.1V ± 2% ON CHIP REFERENCE
    • 7A OUTPUT CURRENT
    • 0 TO 90% DUTY CYCLE RANGE
    • 5.1V TO 40V OUTPUT VOLTAGE RANGE
    • INTERNAL CURRENT LIMITING
    • SOFT START
    • INTERNAL FEED-FORWARD LINE REGULATION

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
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L4977A MW 15L Tube
Active
7.094 10000 EAR99 MOROCCO Check Availability

Distributor availability ofL4977A

Distributor Name
Region Stock Min. Order Third party link
RS COMPONENTS EUROPE 413 1 Order Now
ARROW EUROPE 29 0 Order Now
MOUSER WORLDWIDE 359 1 Order Now

Distributor reported inventory date: 2019-09-15

Distributor Name

RS COMPONENTS

Stock

413

Min.Order

1

Region

EUROPE Order Now

ARROW

Stock

29

Min.Order

0

Region

EUROPE Order Now

MOUSER

Stock

359

Min.Order

1

Region

WORLDWIDE Order Now

Distributor reported inventory date: 2019-09-15

Buy now

L4977A

Package

MW 15L

Packing Type

Tube

Unit Price (US$)

7.094*

Distributor availability ofL4977A

Distributor Name
Region Stock Min. Order Third party link
RS COMPONENTS EUROPE 413 1 Order Now
ARROW EUROPE 29 0 Order Now
MOUSER WORLDWIDE 359 1 Order Now

Distributor reported inventory date: 2019-09-15

Distributor Name

RS COMPONENTS

Stock

413

Min.Order

1

Region

EUROPE Order Now

ARROW

Stock

29

Min.Order

0

Region

EUROPE Order Now

MOUSER

Stock

359

Min.Order

1

Region

WORLDWIDE Order Now

Distributor reported inventory date: 2019-09-15

Marketing Status

Active

Unit Price (US$)

7.094

Quantity

10000

ECCN (US)

EAR99

Country of Origin

MOROCCO

(*) 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**
L4977A
Active
MW 15L Industrial Ecopack1

L4977A

Package:

MW 15L

Material Declaration**:

Marketing Status

Active

Package

MW 15L

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.