2A step-down switching regulator

The L7985/A is a step-down switching regulator with a 2.5 A (minimum) current limited embedded power MOSFET, so it is able to deliver up to 2 A current to the load depending on the application conditions. The input voltage can range from 4.5 V to 38 V, while the output voltage can be set starting from 0.6 V to VIN. Requiring a minimum set of external components, the device includes an internal 250 kHz switching frequency oscillator that can be externally adjusted up to 1 MHz. The QFN and the HSOP packages with exposed pad allow the reduction of RthJAdown to 60 °C/W and 40 °C/W respectively.

Key Features

  • 2 A DC output current
  • 4.5 V to 38 V input voltage
  • Output voltage adjustable from 0.6 V
  • 250 KHz switching frequency, programmable up to 1 MHz
  • Internal soft-start and enable
  • Low dropout operation: 100% duty cycle
  • Voltage feed-forward
  • Zero load current operation
  • Overcurrent and thermal protection
  • VFQFPN 3 x 3 - 10L and HSOP8 package


Technical Documentation

Product Specifications
Description Version Size
DS8733 DS8733: 2 A step-down switching regulator 7.0 1 MB
Design Notes & Tips
Description Version Size
DN0011 DN0011: ST1S03 alternative topology: Using a buck in a negative buck-boost configuration 1.1 359 KB

HW Model, CAD Libraries & SVD

HW Model, CAD Libraries & SVD
Description Version Size
X798X Pspice model 2 MB

Publications and Collaterals

Description Version Size
DC-DC converters 557 KB
Description Version Size
Brochure Power management guide 05.2016 4 MB

Tools and Software

Evaluation Tools
Solution Evaluation Tools
eDesignSuite Support & Community

Sample & Buy

Part Number Package Packing Type Marketing Status Unit Price (US$) * Quantity ECCN (EU) ECCN (US) Country of Origin More info Order from ST Order from Distributors
L7985ATR PowerSO-8 Tape And Reel Active 0.791 1000 NEC EAR99 CHINA MORE INFO Get Sample Add to cart DISTRIBUTOR AVAILABILITY
L7985TR VDFPN 10 3x3x1.0 Tape And Reel Active 0.751 1000 NEC EAR99 PHILIPPINES MORE INFO Get Sample Add to cart DISTRIBUTOR AVAILABILITY

(*) 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

Quality & Reliability

Part Number Marketing Status Package Grade RoHS Compliance Grade Material Declaration**
L7985A ActivePowerSO-8IndustrialEcopack2
L7985ATR ActivePowerSO-8IndustrialEcopack2
L7985TR ActiveVDFPN 10 3x3x1.0IndustrialEcopack2 0 0

(**) 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.