3.5 A step down switching regulator (Vin=8 to 55 V) based on L4973

The STEVAL-ISA090V1 demonstration board provides a platform for evaluation of the L4973, a 3.5 A step-down monolithic power switching regulator operating in continuous mode.

Based on the selection of the external components, the device can operate in the entire input voltage range of 8 V < VIN< 55 V. The output voltage is limited by the voltage rating of the output capacitor, so it can be adjusted within the 3.3 V < VOUT< 30 V range through voltage divider R3, R4. The input and output capacitors are capable of sustaining the RMS current within the operating range.

Key Features

  • Input voltage range: 8 V to 55 V
  • Output voltage: 5.1 V ± 3% (line, load and thermal)
  • Output ripple: 51 mV
  • Output current range: 1 mA to 3.5 A
  • Max output ripple current: 30%
  • Current limit: 4.5 A
  • Switching frequency: 150 kHz
  • RoHS compliant




Technical Documentation

Product Specifications
Description Version Size
DB1266 DB1266: 3.5 A step-down switching regulator based on the L4973 1.1 177 KB

Hardware Resources

Board Manufacturing Specifications
Description Version Size
STEVAL-ISA090V1 gerber files 2.1 99 KB
Bill of Materials
Description Version Size
BOM for STEVAL-ISA090V1 board 1.0 11 KB
Schematic Pack
Description Version Size
Board schematics for STEVAL-ISA090V1 board 1.0 56 KB


License Agreement
Description Version Size
Evaluation products license agreement 1.4 128 KB
Support & Community

Sample & Buy

Part Number Core Product Marketing Status Unit Price (US$) * Quantity ECCN (EU) ECCN (US) Country of Origin More info Order from ST Order from Distributors

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Quality & Reliability

Part Number Marketing Status Package Grade RoHS Compliance Grade Material Declaration**
STEVAL-ISA090V1 ActiveCARDIndustrialEcopack2

(**) 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.