Vishay Siliconix SIC931EVB-A

Overview

SIC931EVB-A from Vishay Siliconix is an evaluation board for the SiC931 20 A synchronous buck DC/DC regulator module, supporting 4.5 V–18 V input and adjustable 0.6 V–5.5 V output. It implements voltage-mode constant-on-time (VM-COT) control with programmable 600 kHz–2 MHz switching, ±1% output accuracy over –40 °C to +125 °C, and integrated power stage in PowerPAK® MLP60-A6C package. Designed for rapid validation of point-of-load (POL) designs in server, industrial computing, and telecom systems.

For engineers reviewing the SIC931EVB-A datasheet, SIC931EVB-A pinout, SIC931EVB-A application, or SIC931EVB-A equivalent, this board enables full characterization of SiC931's transient response, light-load efficiency (down to 1 μA shutdown current), OVP/UVP/OTP protection behavior, soft-start sequencing, and mode configuration via MODE1/MODE2 resistors - all without requiring custom PCB layout.

Technical Context

The SIC931EVB-A implements the SiC931's VM-COT architecture with internal ramp generation, error amplifier compensation, and zero-crossing detection for diode emulation. It supports both forced continuous conduction mode (FCCM) and power-save mode, with user-selectable switching frequencies (600 kHz, 1 MHz, 1.5 MHz, 2 MHz) and current limits (9.6 A–32 A) via external resistor networks on MODE1 and MODE2 pins.

Board-level features include VIN and VOUT sense points, test points for SW, BOOT, GH, GL, FB, PGOOD, EN, and dedicated headers for VCIN, VDD, VDRV, AGND, and PGND. All ceramic input/output capacitors are pre-installed, and the design accommodates pre-bias startup verification and output voltage tracking with external sequencing controllers.

Key Specifications

Availability

SIC931EVB-A is available at Aetrix Electronics and suitable for server power delivery validation, industrial computing POL prototyping, and telecom DC/DC design verification requiring stable component supply and fast time-to-test.

Supply support for SIC931EVB-A includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Vishay Siliconix is a global leader in discrete semiconductors and integrated power solutions, specializing in high-efficiency, high-density power conversion components for demanding industrial, computing, and telecom applications.

The SiC931 product line delivers microBRICK®-format DC/DC modules optimized for ultrafast transient response, minimal external components, and robust protection in space-constrained POL applications - targeting next-generation servers and edge infrastructure.

FAQ

What is the primary function of the SIC931EVB-A evaluation board?

The SIC931EVB-A is a fully assembled and tested reference platform for evaluating the SiC931 20 A synchronous buck regulator module. It enables engineers to validate key performance metrics including efficiency across load ranges, transient response under step-load conditions, soft-start timing, protection activation thresholds (OVP/UVP/OTP), and mode configuration flexibility - all using the exact same PowerPAK® MLP60-A6C packaged IC that ships in production.

Does the SIC931EVB-A support pre-bias startup testing?

Yes, the SIC931EVB-A supports pre-bias startup verification per SiC931 specifications. When the FB pin senses an output voltage higher than the internal 0.6 V reference at power-up, the control logic inhibits switching to prevent negative voltage spikes and excessive current sinking through the low-side MOSFET - a critical capability for systems with powered-backup rails or cascaded converters.

How is switching frequency configured on the SIC931EVB-A?

Switching frequency on the SIC931EVB-A is set by populating a single surface-mount resistor between the MODE1 pin and either AGND (for skip mode) or VDD (for forced CCM), selecting from four factory-trimmed options: 600 kHz, 1 MHz, 1.5 MHz, or 2 MHz. Resistor values are defined in Table 1 of the SiC931 datasheet (S23-0880-Rev. G), and the board provides solder pads and silkscreen labels for each option.

Can the SIC931EVB-A be used to verify output voltage tracking and sequencing?

Yes, the SIC931EVB-A supports output voltage tracking and sequencing via its dedicated EN, PGOOD, and FB interface points. The board exposes all necessary signals - including EN for enable/disable control, PGOOD open-drain output for system power-good signaling, and FB for external monitoring or cascaded feedback - enabling integration into multi-rail sequencing schemes common in FPGAs, ASICs, and processors.

What thermal performance can be expected from the SIC931EVB-A during full-load operation?

Under 20 A continuous load at 12 V_IN/1.2 V_OUT, the SIC931EVB-A achieves ≤150 °C junction temperature with standard airflow (200 LFM), leveraging the SiC931's 2 °C/W R_θJC and the board's exposed thermal pad design. The evaluation board includes a thermal interface pad and optional heatsink mounting holes to replicate production thermal management requirements.