RS18G32 - SVI3, AVSBus 1.4/2.0 & PMBus
Features
Flexible Triple-Rail Multiphase Control
• The RS18G32 supports up to 16 total phases for up to 3 rails (N+M+O ≤ 16)
• Flexible phase allocation from 16+0+0 to 8+4+4
• Native TLVR support with no additional passive components
• Pairs with Reed Smart Power Stages or Smart Power Blocks
Wide Operating Range and High Accuracy
• 4.5V to 16V input
• 0.2V to 2.7V output
• 0.5% accurate output with differential sensing
• ±1.5% voltage and current accuracy
• ±2°C temperature accuracy
High-Performance Regulation
• Programmable phase add/drop for efficiency optimization
• Programmable overshoot/undershoot reduction
• Programmable DC load line
• Thermal balance management
• Up to 4MHz switching frequency
• Internal compensation
Comprehensive protection
• Programmable latch-off or auto-retry fault response
• UVLO, UVP, OVP, OCP, OTP
• Cycle-by-cycle per-phase current limit
Digital Interfaces and Programmability
• SVI3
• AVSBus 1.4/2.0
• PMBus™ v1.4.1
• MTP with up to 31 field-programmable profiles
• Black-box fault recording
Package
• 7mm × 7mm, 60-pin QFN
• RoHS compliant and green
Description
RS18G32 16-Phase Triple-Rail Digital Multiphase Controller
The RS18G32 is a high-performance, triple-output digital multiphase controller designed for demanding processor, accelerator, and computing power applications. Supporting up to 16 total phases with flexible N + M + O ≤ 16 phase allocation, the RS18G32 enables multiple high-current voltage rails to be controlled from a single device while allowing designers to allocate phases according to the power requirements of each rail.
Designed for advanced computing platforms, the RS18G32 combines flexible multiphase control with SVI3, AVSBus, and PMBus digital interfaces. This combination provides a scalable foundation for powering AI accelerators, GPUs, server processors, and other high-performance computing devices requiring precise voltage regulation, fast transient response, comprehensive telemetry, and flexible system-level configuration.
Flexible 16-Phase, Triple-Rail Power Architecture
Modern processors and AI accelerators often require multiple independently regulated high-current rails, with substantially different current and transient requirements for each rail. The RS18G32 addresses these requirements with a triple-rail architecture supporting up to 16 total phases.
Flexible phase allocation allows the available phases to be distributed among the three outputs according to system requirements. Higher-current rails can be assigned additional phases, while lower-current auxiliary processor rails can operate with fewer phases. This flexibility enables designers to optimize a single controller for a wide range of processor and accelerator power architectures.
Consolidating three regulated outputs into one multiphase controller can also help reduce controller count, simplify system architecture, and conserve valuable PCB area in high-density computing platforms.
Native TLVR Support for Fast Transient Performance
The RS18G32 supports Trans-Inductor Voltage Regulator (TLVR) power architectures for applications requiring exceptionally fast response to rapidly changing processor load currents. TLVR is particularly well suited to AI accelerators, GPUs, CPUs, and other high-performance processors where load current can change significantly within very short time intervals.
Native TLVR support allows the controller to take advantage of the rapid transient response of a TLVR power stage while maintaining accurate multiphase regulation. Faster response to load changes can help reduce voltage undershoot and overshoot and potentially reduce the amount of output capacitance required to maintain the processor supply within its allowable voltage window.
This combination of multiphase control and TLVR support makes the RS18G32 well suited for increasingly high-current, high-density core-power applications.
Advanced Digital Control for High-Current Core Power
The RS18G32 provides advanced digital control designed to maintain accurate voltage regulation across changing operating conditions. Multiphase operation distributes current among multiple power stages, reducing the current handled by each individual phase while supporting the high total output currents required by modern computing devices.
Phase allocation can be optimized according to the requirements of each output rail, allowing designers to balance efficiency, power density, transient performance, and thermal performance within the overall power architecture.
This scalable approach is especially valuable as processor power requirements continue to increase. Rather than changing the fundamental controller architecture for each power level, designers can adapt the number and implementation of phases to meet the requirements of the target processor or accelerator.
SVI3, AVSBus and PMBus Digital Interfaces
Support for SVI3 and AVSBus enables the RS18G32 to communicate with supported processors and computing platforms for dynamic voltage control. These high-speed digital interfaces allow processor voltage requirements to be communicated directly to the voltage regulator as operating conditions change.
The integrated PMBus interface provides an additional system-management path for configuration, monitoring, telemetry, and diagnostics. This gives system designers greater visibility into voltage-regulator operation during development and can provide valuable information for power management and system monitoring.
Digital configuration also allows operating parameters to be optimized for the application, providing flexibility across different processor, board, and system designs.
Pair with Reed Smart Power Stages or Smart Power Blocks
The RS18G32 is designed to operate with Reed Smart Power Stages (SPS) and Smart Power Blocks (SPB), enabling designers to build a complete scalable multiphase power solution around the requirements of each output rail.
Reed Smart Power Stages provide a compact single-phase implementation combining the power MOSFETs, gate driver, and monitoring functions required for high-current multiphase conversion. Reed Smart Power Blocks provide a higher level of integration by combining multiple power-stage functions into compact multi-phase building blocks.
The ability to select the appropriate power implementation for each rail gives designers additional flexibility when optimizing for current capability, efficiency, PCB area, transient response, and thermal performance.
As power requirements increase, additional phases can be deployed within the controller’s available 16-phase architecture, providing a scalable path to higher-current processor power.
High-Density Power for AI, GPU and HPC Systems
The combination of 16-phase scalability, three independently controlled outputs, native TLVR support, and multiple digital interfaces makes the RS18G32 particularly well suited to next-generation computing power systems.
Target applications include AI accelerators, GPU core power, server processors, high-performance computing (HPC), graphics cards, and other high-current multi-rail voltage-regulator applications.
By combining the RS18G32 with Reed Smart Power Stages or Smart Power Blocks, designers can create a coordinated controller and power-stage architecture capable of scaling with increasing processor current requirements while maintaining the efficiency, transient performance, telemetry, and power density required by modern AI and computing systems.
