ST1S31

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3 A DC step-down switching regulator

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Product overview

Description

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.

  • All 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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Quality and Reliability

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

ST1S31PUR

Package:

VFDFPN 8 3x3x1.0

Material Declaration**:

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More Info

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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(*) 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

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