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Off-line converters based on buck, or step-down, and buck-boost, or step-down/up, topologies convert the mains to a regulated DC output, either positive or negative, without the need for an isolation transformer by modulating the duty cycle of the power switch.

The waveform of the current in the inductor defines the converter’s mode of operation that can be continuous when the current in the inductor never drops to zero, or discontinuous when the said current stays at zero for a given time interval – and boundary or transition mode when the inductor current is zero at a single point. Both topologies can use a low-cost inductor for energy storage and the transfer from input to output.

Our VIPerPlus high-voltage converters help design high-efficiency, cost-effective off-line buck and buck-boost converters with a minimum component count and enhanced reliability thanks to a set of features including pulse skip protection that can help reduce peak current at start-up allowing the use of smaller, less expensive inductors.

In addition, we provide an extensive set evaluation and development boards as well as reference designs.

Part Number
Description
STEVAL-PMIC1K1 Evaluation board for high integration STPMIC1x power management IC for microprocessor units Quick view

Key Features

  • Single device MPU supply solution embedding:
    • 5 LDOs
    • 5 high efficiency DC/DC converters
    • 1 termination for DDR memory
    • 1 voltage reference for DDR memory
    • 2 power switches
  • Programmable voltage outputs and protection parameters
  • Programmable power-on and power-off sequences
  • Single supply input from 3.1 V to 5.5 V
  • I²C control and non-volatile memory configuration storage

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STEVAL-VP26K01B 15 V / 100 mA high voltage buck converter reference design based on VIPER26K Quick view

Key Features

  • Ultra-wide range: 90–600 VAC or 60–870 VDC
  • Frequency: 50-60 Hz
  • Output voltage: 15 V
  • Output current: 100 mA
  • Very compact size
  • Tight line and load regulation over the entire input and output range
  • Meets IEC55022 Class B conducted EMI even with a reduced EMI filter, thanks to the frequency jittering feature
  • RoHS compliant

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STEVAL-VP12201B 15 V/200 mA buck converter based on VIPER122 Quick view

Key Features

  • Universal input mains range: 85–265 VAC
  • Frequency: 50-60 Hz
  • Output voltage: 15 V
  • Output current: 200 mA
  • Very compact size
  • Stand-by mains consumption: < 30mW at 230 VAC
  • Average efficiency: > 77%
  • Tight line and load regulation over the entire input and output range
  • Meets IEC55022 Class B conducted EMI even with reduced EMI filter, thanks to the frequency jittering feature
  • WEEE compliant
  • RoHS compliant

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STEVAL-ISA195V1 5 V / 0.36 A buck converter using VIPerPlus ? VIPer11 Quick view

Key Features

  • Universal AC main input voltage range: 85 VAC to 265 VAC
  • Output range: 5 V / 0.36 A
  • Rated output power: 1.8 W
  • Input power in standby at 230 VAC : less than 18 mW
  • Active mode efficiency: > 65%
  • EMI: according to EN55022-Class-B
  • RoHS compliant

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STEVAL-ISA179V1 15 V, 0.15 A buck converter using VIPer™ Plus - VIPer0P Quick view

Key Features

  • Universal AC main input voltage range: 85 VAC to 265 VAC
  • Output range: 15 V / 0.15 A
  • Rated output power: 2.25 W
  • Input power in standby @230 VAC : less than 40 mW
  • Active mode efficiency: greater than 77%
  • EMI: EN55022-Class-B compliant
  • RoHS compliant

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STEVAL-ISA178V1 5 V / 200 mA high voltage buck-converter based on VIPer01 Quick view

Key Features

  • Five-star energy efficiency for operation under no load (PIN_no_load < 20 mW @ 230 VAC )
  • Meets ErP Lot 6 Tier 2 requirements for household and office equipment
  • Compliant with the 10% load efficiency and 4-point average active-mode efficiency targets prescribed by the European CoC ver. 5 Tier 2
  • Meets IEC55022 Class B conducted EMI even with reduced EMI filter, thanks to the frequency jittering feature
  • VIPer01 800V avalanche rugged technology and embedded protections ensure enhanced system reliability
  • RoHS compliant

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STEVAL-ISA114V1 5 V/0.8 W wide-range 30 kHz buck converter based on the VIPer06XS Quick view

Key Features

  • Universal input mains range:
    • input voltage: 90 - 264 VAC
    • frequency: 45 - 65 Hz
  • Single-output voltage:
    • 5 V @ 0.16 A continuous operation
  • Fully protected against faults (overload, feedback disconnection and overheating)
  • EMI: according to EN55022-Class-B
  • RoHS compliant

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STEVAL-ISA119V1 1.5 W double output buck demonstration board based on the VIPER16LD Quick view

Key Features

  • Input voltage range (VIN ): 90 VRMS to 265 VRMS
  • Output voltage 1 (VOUT1 )= 12 V
  • Max output current 1: (IOUT1 ) = 0.1 A
  • Output voltage 2: (VOUT2 ) = 5 V (through LDO)
  • Max output current 2: (IOUT2 )= 0.05 A
  • Precision of output regulation ΔVOUT_LF = ±5%
  • High frequency output voltage ripple ΔVOUT_HF = 50 mV
  • Max ambient operating temperature TA = 60 °C

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STEVAL-ISA130V1 12 V 140 mA 30 kHz non-isolated buck topology regulator based on VIPer06XN Quick view

Key Features

  • 800 V avalanche-rugged power section
  • PWM operation current mode controller
  • Limiting current with adjustable set point
  • Fixed frequency with jitter for EMI improvement
  • Operating frequency: 30 kHz
  • Input voltage range: 85 V to 265 V AC or 100 V to 375 V DC
  • Low power application without auxiliary winding
  • No load consumption below 30 mW @ 265 Vac
  • On-board soft-start
  • Auto-restart after a fault condition
  • Feedback disconnection protection
  • Hysteretic thermal shutdown
  • RoHS compliant

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Schematics BOM Gerber
STEVAL-ISA116V1 5 W, 2-output wide-range buck converter based on the VIPER26LD Quick view

Key Features

  • Universal input mains range:
    • input voltage: 80 - 280 VAC
    • frequency: 45 - 65 Hz
  • Double-output voltage:
    • 16 V @ 0.3 A continuous operation
    • 5 V through LDO
  • Standby mains consumption: < 100 mW @ 265 VAC
  • Fully protected against faults (overload, feedback disconnection and overheating)
  • EMI: according to EN55022-Class-B
  • RoHS compliant

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Schematics BOM Gerber
STEVAL-ISA115V1 12 V, 150 mA non-isolated buck converter using VIPer™ Plus - VIPER06XS Quick view

Key Features

  • Universal input mains range:
    • input voltage: 90 VAC - 264 VAC
    • frequency: 45 Hz - 65 Hz
  • Single-output voltage: 12 V @ 0.15 A continuous operation
  • Standby mains consumption: < 50 mW @ 265 VAC
  • Average efficiency: > 75%
  • Fully protected against faults (overload, feedback disconnection and overheating)
  • EMI: in accordance with EN55022-Class-B
  • RoHS compliant

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Schematics BOM Gerber
STEVAL-ISA096V1 Auxiliary power supply in buck-boost topology based on the Viper06 Quick view

Key Features

  • Input voltage: Vin : 85 ~ 264 Vrms; f: 45 ~ 66 Hz
  • Output voltage: -12 Vdc ± 10%, 150 mA
  • Standby < 30 mW at 264 Vac
  • Short-circuit: protected
  • PCB type and size: FR4 single-side 35 μm, 32 x 90 mm
  • Isolation: isolated 4 kV/8 mm
  • EMI: according to EN55022 class B
  • RoHS compliant

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Schematics BOM Gerber
STEVAL-ISA010V1 Ultra wide range dual output back converter demonstration board based on the VIPER16 Quick view

Key Features

  • EMC: burst - IEC 61000-4-4 - 8 kV
  • EMC: surge - IEC 61000-4-5 - 2 kV
  • RoHS compliant
  • Isolation: non isolated - N connected to output GND
  • PCB type and size:FR4, single side 70 μmdim.: 27 x 45 mm
  • Input voltage Vin: 85 - 500 VAC (f: 45 - 66 Hz)
  • Output current: 150 mA total (5 V and 12 V output) output current for full input voltage range
  • Output voltages:V1= 12 V ± 10%V2= 5 V ± 4%
  • Short-circuit protection
  • EMI: In accordance with EN55022 - class B
  • Standby: 96 mW at 230 VAC

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Schematics BOM Gerber
Part Number
STEVAL-PMIC1K1

Evaluation board for high integration STPMIC1x power management IC for microprocessor units

Key Features

  • Single device MPU supply solution embedding:
    • 5 LDOs
    • 5 high efficiency DC/DC converters
    • 1 termination for DDR memory
    • 1 voltage reference for DDR memory
    • 2 power switches
  • Programmable voltage outputs and protection parameters
  • Programmable power-on and power-off sequences
  • Single supply input from 3.1 V to 5.5 V
  • I²C control and non-volatile memory configuration storage

Show More

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FEATURED RESOURCES

Schematics BOM Gerber
STEVAL-VP26K01B

15 V / 100 mA high voltage buck converter reference design based on VIPER26K

Key Features

  • Ultra-wide range: 90–600 VAC or 60–870 VDC
  • Frequency: 50-60 Hz
  • Output voltage: 15 V
  • Output current: 100 mA
  • Very compact size
  • Tight line and load regulation over the entire input and output range
  • Meets IEC55022 Class B conducted EMI even with a reduced EMI filter, thanks to the frequency jittering feature
  • RoHS compliant

Show More

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FEATURED RESOURCES

Schematics BOM Gerber
STEVAL-VP12201B

15 V/200 mA buck converter based on VIPER122

Key Features

  • Universal input mains range: 85–265 VAC
  • Frequency: 50-60 Hz
  • Output voltage: 15 V
  • Output current: 200 mA
  • Very compact size
  • Stand-by mains consumption: < 30mW at 230 VAC
  • Average efficiency: > 77%
  • Tight line and load regulation over the entire input and output range
  • Meets IEC55022 Class B conducted EMI even with reduced EMI filter, thanks to the frequency jittering feature
  • WEEE compliant
  • RoHS compliant

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FEATURED RESOURCES

Schematics BOM Gerber
STEVAL-ISA195V1

5 V / 0.36 A buck converter using VIPerPlus ? VIPer11

Key Features

  • Universal AC main input voltage range: 85 VAC to 265 VAC
  • Output range: 5 V / 0.36 A
  • Rated output power: 1.8 W
  • Input power in standby at 230 VAC : less than 18 mW
  • Active mode efficiency: > 65%
  • EMI: according to EN55022-Class-B
  • RoHS compliant

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FEATURED RESOURCES

Schematics BOM Gerber
STEVAL-ISA179V1

15 V, 0.15 A buck converter using VIPer™ Plus - VIPer0P

Key Features

  • Universal AC main input voltage range: 85 VAC to 265 VAC
  • Output range: 15 V / 0.15 A
  • Rated output power: 2.25 W
  • Input power in standby @230 VAC : less than 40 mW
  • Active mode efficiency: greater than 77%
  • EMI: EN55022-Class-B compliant
  • RoHS compliant

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FEATURED RESOURCES

Schematics BOM Gerber
STEVAL-ISA178V1

5 V / 200 mA high voltage buck-converter based on VIPer01

Key Features

  • Five-star energy efficiency for operation under no load (PIN_no_load < 20 mW @ 230 VAC )
  • Meets ErP Lot 6 Tier 2 requirements for household and office equipment
  • Compliant with the 10% load efficiency and 4-point average active-mode efficiency targets prescribed by the European CoC ver. 5 Tier 2
  • Meets IEC55022 Class B conducted EMI even with reduced EMI filter, thanks to the frequency jittering feature
  • VIPer01 800V avalanche rugged technology and embedded protections ensure enhanced system reliability
  • RoHS compliant

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FEATURED RESOURCES

Schematics BOM Gerber
STEVAL-ISA114V1

5 V/0.8 W wide-range 30 kHz buck converter based on the VIPer06XS

Key Features

  • Universal input mains range:
    • input voltage: 90 - 264 VAC
    • frequency: 45 - 65 Hz
  • Single-output voltage:
    • 5 V @ 0.16 A continuous operation
  • Fully protected against faults (overload, feedback disconnection and overheating)
  • EMI: according to EN55022-Class-B
  • RoHS compliant

Show More

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FEATURED RESOURCES

Schematics BOM Gerber
STEVAL-ISA119V1

1.5 W double output buck demonstration board based on the VIPER16LD

Key Features

  • Input voltage range (VIN ): 90 VRMS to 265 VRMS
  • Output voltage 1 (VOUT1 )= 12 V
  • Max output current 1: (IOUT1 ) = 0.1 A
  • Output voltage 2: (VOUT2 ) = 5 V (through LDO)
  • Max output current 2: (IOUT2 )= 0.05 A
  • Precision of output regulation ΔVOUT_LF = ±5%
  • High frequency output voltage ripple ΔVOUT_HF = 50 mV
  • Max ambient operating temperature TA = 60 °C

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FEATURED RESOURCES

Schematics BOM Gerber
STEVAL-ISA130V1

12 V 140 mA 30 kHz non-isolated buck topology regulator based on VIPer06XN

Key Features

  • 800 V avalanche-rugged power section
  • PWM operation current mode controller
  • Limiting current with adjustable set point
  • Fixed frequency with jitter for EMI improvement
  • Operating frequency: 30 kHz
  • Input voltage range: 85 V to 265 V AC or 100 V to 375 V DC
  • Low power application without auxiliary winding
  • No load consumption below 30 mW @ 265 Vac
  • On-board soft-start
  • Auto-restart after a fault condition
  • Feedback disconnection protection
  • Hysteretic thermal shutdown
  • RoHS compliant

Show More

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FEATURED RESOURCES

Schematics BOM Gerber
STEVAL-ISA116V1

5 W, 2-output wide-range buck converter based on the VIPER26LD

Key Features

  • Universal input mains range:
    • input voltage: 80 - 280 VAC
    • frequency: 45 - 65 Hz
  • Double-output voltage:
    • 16 V @ 0.3 A continuous operation
    • 5 V through LDO
  • Standby mains consumption: < 100 mW @ 265 VAC
  • Fully protected against faults (overload, feedback disconnection and overheating)
  • EMI: according to EN55022-Class-B
  • RoHS compliant

Show More

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FEATURED RESOURCES

Schematics BOM Gerber
STEVAL-ISA115V1

12 V, 150 mA non-isolated buck converter using VIPer™ Plus - VIPER06XS

Key Features

  • Universal input mains range:
    • input voltage: 90 VAC - 264 VAC
    • frequency: 45 Hz - 65 Hz
  • Single-output voltage: 12 V @ 0.15 A continuous operation
  • Standby mains consumption: < 50 mW @ 265 VAC
  • Average efficiency: > 75%
  • Fully protected against faults (overload, feedback disconnection and overheating)
  • EMI: in accordance with EN55022-Class-B
  • RoHS compliant

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FEATURED RESOURCES

Schematics BOM Gerber
STEVAL-ISA096V1

Auxiliary power supply in buck-boost topology based on the Viper06

Key Features

  • Input voltage: Vin : 85 ~ 264 Vrms; f: 45 ~ 66 Hz
  • Output voltage: -12 Vdc ± 10%, 150 mA
  • Standby < 30 mW at 264 Vac
  • Short-circuit: protected
  • PCB type and size: FR4 single-side 35 μm, 32 x 90 mm
  • Isolation: isolated 4 kV/8 mm
  • EMI: according to EN55022 class B
  • RoHS compliant

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FEATURED RESOURCES

Schematics BOM Gerber
STEVAL-ISA010V1

Ultra wide range dual output back converter demonstration board based on the VIPER16

Key Features

  • EMC: burst - IEC 61000-4-4 - 8 kV
  • EMC: surge - IEC 61000-4-5 - 2 kV
  • RoHS compliant
  • Isolation: non isolated - N connected to output GND
  • PCB type and size:FR4, single side 70 μmdim.: 27 x 45 mm
  • Input voltage Vin: 85 - 500 VAC (f: 45 - 66 Hz)
  • Output current: 150 mA total (5 V and 12 V output) output current for full input voltage range
  • Output voltages:V1= 12 V ± 10%V2= 5 V ± 4%
  • Short-circuit protection
  • EMI: In accordance with EN55022 - class B
  • Standby: 96 mW at 230 VAC

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00 Files selected for download

Technical Documentation

    • Description Version Size Action
      AN4260
      12 V, 150 mA non-isolated buck converter using the VIPER06XS, from the VIPer™ plus family
      4.2
      3.5 MB
      PDF
      AN1768
      ADMISSIBLE AVALANCHE POWER OF SCHOTTKY DIODES
      1.1
      46.82 KB
      PDF
      AN2025
      CONVERTER IMPROVEMENT USING SCHOTTKY RECTIFIER AVALANCHE SPECIFICATION
      1.1
      147.59 KB
      PDF
      AN604
      Calculation of conduction losses in a power rectifier
      3.2
      137.74 KB
      PDF
      AN4021
      Calculation of reverse losses in a power diode
      1.0
      120.47 KB
      PDF
      AN1453
      NEW FAMILY OF 150V POWER SCHOTTKY
      1.1
      131.48 KB
      PDF
      AN5046
      Printed circuit board assembly recommendations for STMicroelectronics PowerFLAT packages
      4.0
      4.82 MB
      PDF
      AN5088
      Rectifiers thermal management, handling and mounting recommendations
      2.0
      2.32 MB
      PDF
      AN443
      SERIES OPERATION ON FAST RECTIFIERS
      2.1
      202.48 KB
      PDF
      AN4273
      STEVAL-ISA114V1: 5 V / 0.8 W 30 kHz buck with the VIPer06XS
      3.0
      978.71 KB
      PDF
      AN4562
      STEVAL-ISA116V1: 5 W, 2 output wide range buck converter based on the VIPER26LD
      1.0
      896.83 KB
      PDF
      AN4345
      STEVAL-ISA119V1: 1.5 W double output buck product evaluation board based on the VIPER16LD
      1.0
      2.84 MB
      PDF
      AN4858
      STEVAL-ISA178V1 5 V/1 W 30 kHz buck demo with VIPer01
      1.0
      1.84 MB
      PDF
      AN4857
      STEVAL-ISA179V1 15 V/2.25 W 60 kHz buck demo with VIPer0P
      1.0
      1.61 MB
      PDF
      AN2872
      Super wide-range buck converter based on the VIPer16
      1.2
      581.24 KB
      PDF
      AN869
      Tj max limit of Schottky diodes
      2.2
      60.9 KB
      PDF
      AN4260

      12 V, 150 mA non-isolated buck converter using the VIPER06XS, from the VIPer™ plus family

      AN1768

      ADMISSIBLE AVALANCHE POWER OF SCHOTTKY DIODES

      AN2025

      CONVERTER IMPROVEMENT USING SCHOTTKY RECTIFIER AVALANCHE SPECIFICATION

      AN604

      Calculation of conduction losses in a power rectifier

      AN4021

      Calculation of reverse losses in a power diode

      AN1453

      NEW FAMILY OF 150V POWER SCHOTTKY

      AN5046

      Printed circuit board assembly recommendations for STMicroelectronics PowerFLAT packages

      AN5088

      Rectifiers thermal management, handling and mounting recommendations

      AN443

      SERIES OPERATION ON FAST RECTIFIERS

      AN4273

      STEVAL-ISA114V1: 5 V / 0.8 W 30 kHz buck with the VIPer06XS

      AN4562

      STEVAL-ISA116V1: 5 W, 2 output wide range buck converter based on the VIPER26LD

      AN4345

      STEVAL-ISA119V1: 1.5 W double output buck product evaluation board based on the VIPER16LD

      AN4858

      STEVAL-ISA178V1 5 V/1 W 30 kHz buck demo with VIPer01

      AN4857

      STEVAL-ISA179V1 15 V/2.25 W 60 kHz buck demo with VIPer0P

      AN2872

      Super wide-range buck converter based on the VIPer16

      AN869

      Tj max limit of Schottky diodes

    • Description Version Size Action
      UM1470
      STEVAL-ISA096V1 -12 V/150 mA adaptable buck-boost converter
      1.0
      931.46 KB
      PDF
      UM1470

      STEVAL-ISA096V1 -12 V/150 mA adaptable buck-boost converter

    • Description Version Size Action
      DN0009
      VIPer06X buck regulator, 12V 140 mA
      1.2
      493.06 KB
      PDF
      DN0009

      VIPer06X buck regulator, 12V 140 mA

Publications and Collaterals

    • Description Version Size Action
      SOD128Flat power Schottky diodes for improved cost and space-savings 1.0
      2.18 MB
      PDF

      SOD128Flat power Schottky diodes for improved cost and space-savings

    • Description Version Size Action
      VIPerPlus - Bring a Plus to your SMPS design 11.2019
      1.18 MB
      PDF

      VIPerPlus - Bring a Plus to your SMPS design

Development Tools

    • Part Number

      Diode product finder application for Android and iOS

      Linear and switching voltage regulators and voltage reference applications for smartphones and tablets

Diodes and Rectifiers

Part number Description
STTH108 800 V, 1 A Ultrafast Diode
STTH112 1200 V, 1A Ultrafast Diode
STTH15RQ06 600 V, 15 A Turbo 2 Soft Ultrafast Recovery Diode
Part number
800 V, 1 A Ultrafast Diode
1200 V, 1A Ultrafast Diode
600 V, 15 A Turbo 2 Soft Ultrafast Recovery Diode
Support & Feedback