38 V, 1.5 A synchronous step-down converter with 20 µA quiescent current

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Product overview

Description

The L6981 is an easy to use synchronous monolithic step-down regulator capable of delivering up to 1.5 A DC to the load. The wide input voltage range makes the device suitable for a broad range of applications. The L6981 is based on a peak current mode architecture and is packaged in an SO8 with internal compensation, thus minimizing design complexity and size.

The L6981 is available both in low consumption mode (LCM) and low noise mode (LNM) versions. LCM maximizes the efficiency at light-load with controlled output voltage ripple so the device is suitable for battery-powered applications.

LNM makes the switching frequency constant and minimizes the output voltage ripple for light-load operations, meeting the specification for low noise sensitive applications.

The EN pin provides output enable/disable functionality. The typical shutdown current is 2 µA when disabled. As soon as the EN pin is pulled up the device is enabled and the internal 1.3 ms soft-start takes place. Pulse-by-pulse current sensing on both power elements implements an effective constant current protection and thermal shutdown prevents thermal run-away.

  • All features

    • 3.5 V to 38 V operating input voltage
    • Output voltage from 0.85 V to VIN
    • 3.3 / 5 V fixed output voltage versions
    • 1.5 A DC output current
    • 20 μA operating quiescent current
    • Internal compensation network
    • Two different versions: LCM for high efficiency at light-loads and LNM for noise sensitive applications
    • 2 μA shutdown current
    • Internal soft-start
    • High voltage VIN compatible Enable
    • Output overvoltage protection
    • Output voltage sequencing
    • Thermal protection
    • Synchronization to external clock for LNM devices
    • SO8 package

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EDA Symbols, Footprints and 3D Models

STMicroelectronics - L6981

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Quality and Reliability

Part Number Marketing Status Package Grade RoHS Compliance Grade Material Declaration**
L6981C33DR
Active
SO-8 Industrial Ecopack2
L6981C50DR
Active
SO-8 Industrial Ecopack2
L6981CDR
Active
SO-8 Industrial Ecopack2
L6981N33DR
Active
SO-8 Industrial Ecopack2
L6981N50DR
Active
SO-8 Industrial Ecopack2
L6981NDR
Active
SO-8 Industrial Ecopack2

L6981C33DR

Package:

SO-8

Material Declaration**:

Marketing Status

Active

Package

SO-8

Grade

Industrial

RoHS Compliance Grade

Ecopack2

L6981C50DR

Package:

SO-8

Material Declaration**:

Marketing Status

Active

Package

SO-8

Grade

Industrial

RoHS Compliance Grade

Ecopack2

L6981CDR

Package:

SO-8

Material Declaration**:

PDF XML

Marketing Status

Active

Package

SO-8

Grade

Industrial

RoHS Compliance Grade

Ecopack2

L6981N33DR

Package:

SO-8

Material Declaration**:

Marketing Status

Active

Package

SO-8

Grade

Industrial

RoHS Compliance Grade

Ecopack2

L6981N50DR

Package:

SO-8

Material Declaration**:

Marketing Status

Active

Package

SO-8

Grade

Industrial

RoHS Compliance Grade

Ecopack2

L6981NDR

Package:

SO-8

Material Declaration**:

PDF XML

Marketing Status

Active

Package

SO-8

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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L6981CDR
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L6981NDR
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L6981C33DR
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L6981C50DR Active

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L6981N50DR

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L6981N33DR Active

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L6981N33DR

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L6981CDR Active

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L6981CDR

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L6981NDR Active

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L6981NDR

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L6981C33DR Active

Budgetary Price (US$)*/Qty:
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Package:
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ECCN (EU):

Part Number:

L6981C33DR

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(*) Suggested Resale Price (USD) per defined quantity for BUDGETARY USE ONLY. For quotes, prices in local currency, please contact your local ST Sales Office or our Distributors