Frequently Asked Questions - Power System Solutions

DCM (DC-DC Converter Module): Fixed-ratio, isolated converter without regulation. Ideal for bus conversion with galvanic isolation.

BCM (Bus Converter Module): Current multiplication with galvanic isolation. Used for applications requiring current multiplication with voltage transformation.

PRM (Propensity Regulated Module): Regulated bus converter providing precise voltage regulation with high efficiency.

VTM (Vicor Transformer Module): Current multiplication transformer used in Factorized Power Architecture (FPA) with PRM. Provides current multiplication with galvanic isolation while preserving dynamic response.

Factorized Power Architecture separates voltage transformation and regulation functions using a PRM (regulator) and VTM (current multiplier). The PRM provides precise regulation and the VTM provides current multiplication with voltage transformation while preserving the dynamic response of the power delivery network. This enables high-current, fast-transient power delivery with galvanic isolation.

Zero Voltage Switching (ZVS) technology significantly reduces switching losses by turning transistors on and off when the voltage across them is zero. This results in higher efficiency, lower electromagnetic interference (EMI), and reduced thermal dissipation. ZVS is particularly beneficial at higher frequencies and higher power levels.

Galvanic isolation is required when you need to: 1) Prevent ground loops between input and output 2) Meet safety requirements for human contact 3) Protect sensitive circuits 4) Handle floating voltage inputs. Common applications include medical equipment, automotive systems, and communication equipment.

ChiP technology houses the entire power converter within a surface-mount package with all components fully integrated. This eliminates the need for external components like magnetics and capacitors, resulting in higher power density, smaller solution size, and simplified manufacturing. ChiP modules are ideal for space-constrained and high-performance applications.

ChiP (Converter housed in Package) integrates the entire converter in a single package with no external components required. VIA (Vertical Integrated Array) arranges power components in a vertical configuration within a compact package but may still require some external components. ChiP typically offers higher power density, while VIA provides a cost-effective solution with good performance.

Most Vicor modules are designed for surface mount applications on horizontal PCBs. However, some packages can be mounted vertically with proper mechanical reinforcement and adherence to specific layout guidelines. Contact our FAE team for specific mounting recommendations for your module.

Junction temperature can be calculated as: Tj = Ta + Pd × Rthja, where Tj is junction temperature, Ta is ambient temperature, Pd is power dissipation (Vin×Iin - Vout×Iout), and Rthja is junction-to-ambient thermal resistance. Consider worst-case operating conditions for design calculations and ensure Tj remains below the maximum rating in the datasheet.

PCB layout is critical for thermal performance. Proper use of copper for heat spreading, thermal vias for heat transfer to internal layers, and connection to large copper areas significantly impact thermal performance. Modules with exposed thermal pads should be connected to copper areas for optimal thermal management.

Many applications operate within thermal limits using PCB copper for heat spreading and natural convection. A heat sink is typically needed for high-power applications, high ambient temperatures, or applications with limited PCB area available for heat spreading. Calculate junction temperature for your conditions to determine if additional thermal management is needed.

For 48V systems, consider: 1) Use DCMs for simple 48V to intermediate voltage conversion with isolation 2) Use BCMs for current multiplication with isolation 3) Use FPA (PRM+VTM) for high-current loads requiring regulation with preserved dynamics 4) Consider using multiple conversion stages if required. Evaluate efficiency, power density, and cost for your specific requirements.

Fixed-ratio converters (like DCM) maintain a constant voltage ratio between input and output. For example, a 4:1 ratio DCM outputs 12V if input is 48V, and 10V if input is 40V. Regulated converters (like PRM) maintain a constant output voltage regardless of input voltage variations. Use fixed-ratio for applications where input voltage is stable and regulation is not required. Use regulation when input voltage varies significantly or tight output voltage tolerance is required.

DCM modules can be paralleled naturally due to their droop characteristics which promote current sharing. BCM and VTM modules can also be paralleled for higher current applications. PRM modules can be paralleled but may require additional circuitry for effective current sharing. Always refer to specific product documentation for paralleling guidelines and limitations.

Vicor modules include several protection features: Over-temperature protection, input over-voltage protection, output over-current limit, and short-circuit protection. Specific features vary by product family and model. Details are available in individual product datasheets. Some modules also feature bidirectional operation and ultrasonic silent operation modes.

To minimize EMI: 1) Use ChiP packages which have inherently low EMI due to minimized loop area 2) Place input and output capacitors close to the power module terminals 3) Implement proper ground planes and return paths 4) Use common mode chokes if needed 5) Consider spread-spectrum modulation if available 6) Minimize high di/dt loops through careful layout. For best results, simulate and measure EMI in your final application.

Required capacitance values depend on the specific module, application requirements, and EMI specifications. The minimum capacitance values and recommended types are specified in the product datasheets. Typically, high-frequency ceramic capacitors are placed closest to the module terminals to provide charge for high-frequency switching currents. Bulk capacitance is added based on low-frequency ripple requirements and holdup time requirements.

Traditional power architecture uses a regulator near the load (POL). FPA (Factorized Power Architecture) uses a PRM (regulator) at the input and a VTM (current multiplier) near the load. This separation provides several benefits: 1) Preserved dynamic response of the power delivery network 2) Galvanic isolation 3) Current multiplication 4) Better utilization of available input bus voltage for load delivery. FPA is ideal for high-current applications with fast transient requirements.

Vicor modules are designed for long-term reliability with no wear-out mechanisms like electrolytic capacitors. Typical design life exceeds 100,000 hours at rated conditions. Lifetime is affected by operating temperature, with every 10°C increase approximately halving the component lifetime. Proper thermal management is critical for realizing the long design life. Many applications demonstrate 15+ year operational life in field installations.

Vicor products are manufactured to meet demanding quality standards: ISO 9001 certified manufacturing, AEC-Q100 qualified parts for automotive applications, MIL-PRF-38534 compliant manufacturing for military applications, and IEC 60068 environmental testing. Vicor also performs extensive in-house reliability testing including HTOL (High Temperature Operating Life), temperature cycling, and humidity testing.

Vicor modules are designed for harsh environment applications. They operate from -40°C to +105°C (derated at elevated temperatures) with some models extending to +125°C. The hermetically sealed packages protect against moisture and contamination. The design has high vibration and shock tolerance making it suitable for aerospace, automotive, and industrial applications. Conformal coating can be applied for additional environmental protection when needed.

Bidirectional power flow requires modules that support reverse conduction and control. NBM (Non-Breaking Module) Bus Matrix Family products are specifically designed for bidirectional applications. They enable seamless power flow between two voltage domains, useful for backup power systems, battery charging, and other bidirectional applications. Control logic manages the power flow direction based on system requirements.

Yes, many applications use Vicor modules in redundant configurations. DCM modules can be easily paralleled for N+1 redundancy. For systems requiring OR-ing, additional control or discrete OR-ing circuits may be required. For FPA systems (PRM+VTM), both the PRM and VTM need to be implemented in redundant configurations. Contact our FAE team to develop the optimal redundant architecture for your application.

DCM modules have a fixed voltage ratio that cannot be adjusted. For example, a 4:1 ratio DCM will always output 1/4 the input voltage. To achieve different output voltages, you must select a DCM with the appropriate turns ratio. For applications requiring adjustable output voltage, consider using a PRM with adjustable feedback configuration or a traditional regulator.

SPICE models for many Vicor power modules are available through our online design tools. These models include both electrical and thermal characteristics for accurate system simulation. Visit our design tools section or contact our support team to access the appropriate models for your specific module.

Vicor provides several design tools: online power system configurators, SPICE models for simulation, efficiency calculators, thermal calculators, and reference design examples. Our Power System Configurator helps you quickly select appropriate solutions for your requirements. Webinar recordings and application notes provide additional design guidance.

Technical support is available through multiple channels: local FAEs for application-specific support, online design tools for preliminary design work, application notes for design guidance, and reference designs for common applications. Contact us through our website or your local representative for design assistance, layout review, and system optimization recommendations.