Featured Applications Note:

DC-DC Converters

• Micro Family Isolated Remote Sense

  (6 pages, 412k)
  Vicor’s Micro DC-DC converters do not have remote sense pins. Nevertheless, remote sense can be achieved by employing external circuitry. A circuit is proposed that senses the voltage at the load and adjusts the converter output voltage to compensate for the voltage drop in the leads / traces. It also provides isolation of the sense leads / traces that is beneficial in high-noise applications.
  
  

• Converter PR Pin Facilitates Parallel Operation for Power Expansion or Redundancy

  (2 pages, 84k)
  A unique feature has been designed into Vicor's Maxi, Mini and Micro converter modules which facilitates parallel operation for power expansion or redundancy.
  
  

• Hot Swap Capability Eliminates Downtime

  (4 pages, 44k)
  Hot swap capability imposes special needs to insure survival of the component which is subjected to live insertion and extraction. In addition, it is necessary to prevent any significant disturbance of either input or output power rails during live insertion / extraction.
  
  

• Wide Range Trimming with Variable Loads

  (2 pages, 37k)
  The output of Vicor 2nd Generation DC-DC converter modules can be programmed from 10 to 110% of their nominal output voltage. Trimming down is easily accomplished with a small low power resistor or potentiometer connected between the SC pin and the -S pin.
  
  

• Component Power Solutions for Industrial High Voltage Applications

  (3 pages, 123k)
  State-of-the-art Vicor Maxi, Mini, Micro Series DC-DC converters offer many features that facilitate their integration into a complete power solution. Foremost of these is a unique current sharing schemewhich allows for increased power capability, with current sharing accuracy between modules better than 5%.
  
  

• High Efficiency Battery Charger Using Power Components

  (4 pages, 128k)
  An offline battery charger — using the Unitrode UC3906 battery charger controller chip and a Vicor Maxi, Mini, Micro Series DC-DC converter module — provides design flexibility, small size, and highefficiency. The system is described, and an estimate of overall efficiency of the battery charger is derived.
  
  

• Thermal Considerations: Assuring Performance of Maxi, Mini and Micro High-Density DC-DC Converter Modules

  (3 pages, 104k)
  As the modular DC-DC converter industry realizes greater power densities, proper thermal management must be achieved in order to get the most usable power to the load. Efficiency, while an important element in thermal management, is not the only item to consider. Dealing with the heat generated by the conversion process should not be underestimated nor overlooked when designing or selecting a power supply.
  
  

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VI BRICKS™

• AN – VI BRICK THERMAL MANAGEMENT

  (8 pages, 572k)
  VI BRICKs allow access to the advantages of Vicor’s V•I Chip technology with increased options for thermal management. High operating efficiency minimizes heat loss, and the thermally enhanced low profile package features an easily accessible, electrically isolated thermal interface surface.
  

• AN:001 – Configuring the Vicor BCM with low power niPOLs

  (4 pages, 253k)
  The niPOLs within IBA forego isolation and high–ratio voltage transformation in order to improve cost effectiveness, and they depend upon a nearby bus converter to supply isolated power at a low voltage. The 48 V to 12 V (K = 1/4) BCM can be placed at the power entry point on the board. This will provide safety isolation from the higher 48 V backplane voltage as well as free up board space at the point–of–load.
  
  

• AN:002 – PRM/VTM Parallel Operation

  (4 pages, 44k)
  This applications note describes the steps needed to create a current sharing higher power array using two PRM-AL and VTM pairs in a parallel configuration. If the application requires more than two PRMs in parallel, please contact Applications Engineering for additional information.
  
  

• AN:003 Powering Multiple VTMs with a Single PRM

  (3 pages, 337k)
  This Applications Note discusses the design practices for using Vicor’s V•I Chip Pre-Regulator Module and Voltage Transformation Module to meet the challenge of power systems that require lower voltages, more current, and multiple voltages within one system. Vicor’s V•I Chips can address these challenges.
  
  

• AN:005 FPA Printed Circuit Board Layout Guidelines

  (10 pages, 522k)
  Factorized Power with V•I Chips enable system density to keep pace with technology by providing layout flexibility and high power density. More importantly, V•I Chips allow a power conversion system to be "factorized" or separated into its constituent functions.
  
  

• AN:007 Using VTMs as 26 – 55 V Input Bus Converters

  (3 pages, 243k)
  The Voltage Transformation Module (VTM) is a fundamental building block of Factorized Power Architecture (FPA). This new power conversion architecture separates the functions of the DC-DC converter – regulation, isolation, and transformation – into two building blocks.
  
  

• AN: 016 Using BCM™ Bus Converters in High Power Arrays

  (6 pages, 644k)
  This application note provides methods and guidelines for designing BCMs into high power arrays.
  
  

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V•I Chips

• AN:001 – Configuring the Vicor BCM with low power niPOLs

  (4 pages, 253k)
  The niPOLs within IBA forego isolation and high–ratio voltage transformation in order to improve cost effectiveness, and they depend upon a nearby bus converter to supply isolated power at a low voltage. The 48 V to 12 V (K = 1/4) BCM can be placed at the power entry point on the board. This will provide safety isolation from the higher 48 V backplane voltage as well as free up board space at the point–of–load.
  
  

• AN:002 – PRM/VTM Parallel Operation

  (4 pages, 44k)
  This applications note describes the steps needed to create a current sharing higher power array using two PRM-AL and VTM pairs in a parallel configuration. If the application requires more than two PRMs in parallel, please contact Applications Engineering for additional information.
  
  

• AN:003 Powering Multiple VTMs with a Single PRM

  (3 pages, 337k)
  This Applications Note discusses the design practices for using Vicor’s V•I Chip Pre-Regulator Module and Voltage Transformation Module to meet the challenge of power systems that require lower voltages, more current, and multiple voltages within one system. Vicor’s V•I Chips can address these challenges.
  
  

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• AN:005 FPA Printed Circuit Board Layout Guidelines

  (10 pages, 522k)
  Factorized Power with V•I Chips enable system density to keep pace with technology by providing layout flexibility and high power density. More importantly, V•I Chips allow a power conversion system to be "factorized" or separated into its constituent functions.
  
  

• AN:006 A Filter Solution for the BCM

  (7 pages, 602k)
  The Bus Converter Module (BCM) is a member of Vicor's Factorized Power Architecture family of V•I Chips. It provides an isolated intermediate bus voltage to power non-isolated point-of-load (POL) converters from a narrow input range DC source.
  
  

• AN:007 Using VTMs as 26 – 55 V Input Bus Converters

  (3 pages, 243k)
  The Voltage Transformation Module (VTM) is a fundamental building block of Factorized Power Architecture (FPA). This new power conversion architecture separates the functions of the DC-DC converter – regulation, isolation, and transformation – into two building blocks.
  
  

• AN:008 V•I Chip Bus Converter Module (BCM) Thermal Management

  (27 pages, 3,834k)
  The purpose of this Applications Note is to determine the power capability of the BCMs given certain ambient temperature and air flow conditions plus heat sink options.
  
  

• AN: 009 V•I Chip Soldering Recommendations

  (4 pages, 261k)
  V•I Chips are intended for reflow soldering assembly. The information contained in this document defines the processing conditions required for successful attachment to a PCB. Failure to follow the recommendations provided can result in aesthetic and functional failure of the module.
  
  

• AN: 016 Using BCM™ Bus Converters in High Power Arrays

  (6 pages, 644k)
  This application note provides methods and guidelines for designing BCMs into high power arrays.
  
  

• AN: 017 RoHS-Compliant Through-Hole V•I Chip Soldering Recommendations

  (9 pages, 556k)
  RoHS compliant, through-hole full size V•I Chips are intended for wave soldering assembly. The information contained in this document defines the processing conditions required for mounting a full size V•I Chip to the PCB using wave soldering or hand soldering.
  
  

• AN: 018 Providing a Constant Current for Powering LEDs using the PRM and VTM

  (21 pages, 2.2MB)
  Light Emitting Diodes (LEDs) require a constant current for proper operation. In order to use the PRM and VTM to power an LED, it is necessary to modify the operation of the PRM to provide a regulated current. This application note provides guidelines for implementing that constant current source using the chipset.
  
  

• AN: 022 MIL EMI and Transient Solutions

  (14 pages, 973k)
  28 Volt defense applications must meet a number of noise and power related standards such as MIL-STD-461, MIL-STD-704, and MIL-STD-1275.
  
  

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Filter/AC Front Ends

• Off-line Power Supply using the FARM AC Front End Module

  (5 pages, 160k)
  An autoranging, high density, low profile switching power supply can be realized using Vicor DC-DC converters and an AC front-end module (FARM).

• Power Components Simplify 1kW Power Design

  (7 pages, 370k)
  Not long ago, designing a 1,000 W power supply for operation on worldwide AC lines was a task for the most experienced power design engineers. Besides dealing with the design of autoranging front-end rectification circuitry and isolated power conversion stages, the designer faced a myriad of other complex technical and design issues: inrush current limiting, sizing and selection of holdup capacitors, transient protection, thermal design, and worldwide safety agency and conducted noise requirements.

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Other

• Line Filter, VI-HAM Harmonic Attenuator Module

  (1 pages, 56k)
  The VI-HAM Harmonic Attenuator Module requires an external filter to meet international standards for EMI / RFI emissions, and incorporates transient surge protection.

• Meeting transient specifications for electrical systems in military vehicles

  (8 pages, 208k)
  Electrical systems in military vehicles are normally required to meet stringent transient requirements. Typical of these specifications are MIL-STD-1275B in the U.S.A. and DEF-STAN 61-5 (Part 6 )/ Issue 5 in the UK. Although the specified levels of these surges and spikes are outside the capability of Vicor Maxi, Mini and Micro modules, it is quite possible, with simple circuitry, to make the 24 V input (18 – 36 V input range) DC-DC converter modules compliant to these specifications for the 28 V vehicle voltage system.

• Current Share Board

  (2 pages, 35k)
  "Current sharing" also known as load sharing, is the ability to divide the output current evenly across all active power supplies. This greatly reduces stresses on each power supply and allows them to run cooler resulting in higher reliability. Standard “current sharing” techniques typically utilize shunt resistors or Hall-Effect devices to . measure the current from each power supply. Power shunt resistors continually dissipate power and require cooling . especially when dealing with high output currents of >100 Amps.

• Adjustable Latching Output Over Current Circuit

  (4 pages, 245k)
  Many users, for logistical reasons, employ a particular module for many applications at significantly lower power than the unit is able to provide. The potential damage to down stream PCB traces and components caused by the module high current source capability creates a need for an adjustable latching output current limit circuit.

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• Active PFC for Electronic Power Supplies

  (2 pages, 24k)
  When choosing a strategy for PFC, it is essential to recognize that the poor power factor occurring in electronic power conversion equipment is entirely different from the traditional poor power factor seen with inductive motor loads, and requires a different corrective approach.

• Controlling the BatMod with a Digital Potentiometer

  (2 pages, 36k)
  The BatMod is a modular, component level DC-DC converter that provides a programmable output voltage and current limit suitable for battery charging or other applications that require constant current with external control.

• Designing a Battery Charger

  (2 pages, 28k)
  Vicor's BatMod current source module enables designers to easily build a compact, lightweight battery charging system with commonly available parts.

• Using Modular DC-DC Converters to Meet European Standards for Railway Applications

  (3 pages, 40k)
  This Applications Note shows how to comply with these standards using modular Vicor DC-DC converters to facilitate the design of complex power supplies.

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• Creating High Voltage Outputs

  (1 pages, 40k)
  This Applications Note describes two approaches to producing a high voltage output. One solution provides a fixed output voltage, the other an adjustable output voltage.

• Designing a Power Supply with Multiple Input Options

  (1 pages, 24k)
  Some electronic systems such as field communications equipment must be able to operate from a variety of power sources. These systems may also require backup power in case the primary source is interrupted.

• Meeting Conducted Noise Standards

  (2 pages, 36k)
  Finding an efficient, compact solution to meeting EMI requirements is a greater challenge than ever. Here's how to meet the strict limits of FCC / VDE Class B using industry standard high density components.

• Powering Dynamic Loads

  (2 pages, 32k)
  This document illustrates Vicor converters' current limiting safety feature and design strategies that will allow your power system to maintain stable output voltages and sufficient available power levels in applications with widely and / or rapidly fluctuating loads.

• Soldering Methods and Procedures for Vicor Power Modules

  (10 pages, 196k)
  The following pages contain soldering information for the following Vicor product families; Maxi, Mini, Micro; VE-200, VE-J00; VI BRICK, and similar package filters and front-ends.

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