Analog Devices Inc. LTC3883IUH

Overview

LTC3883IUH from Analog Devices is a dual-output, polyphase synchronous step-down DC/DC controller with integrated PMBus interface, precision voltage regulation (±0.5% over line/load/temp), and real-time telemetry. It supports SmartVID2-compliant voltage scaling for FPGAs like Altera Arria 10 and Xilinx Virtex UltraScale, delivers up to 13 A per phase via external MOSFETs, and operates from 4.5 V to 26.5 V input.

For engineers reviewing the LTC3883IUH datasheet, LTC3883IUH pinout, LTC3883IUH application, or LTC3883IUH equivalent, this controller enables deterministic power-up/down sequencing, autonomous fault response via shared FAULT bus, accurate core voltage optimization under SmartVID2, and time-based synchronization across multi-rail systems using SHARE_CLK.

Technical Context

The LTC3883IUH implements a dual-loop voltage-mode control architecture with programmable loop compensation, supporting up to two independent output rails or interleaved operation for higher current. It integrates a 16-bit ADC for voltage, current, temperature, and duty cycle monitoring, with telemetry reported via PMBus v1.3.

It features hardware-based sequencing coordination through SHARE_CLK (100 kHz open-drain timing bus) and FAULT (open-drain fault broadcast bus), enabling synchronized ramp-up/ramp-down across multiple PSM ICs without host intervention. Its SmartVID2 support includes VOUT_MODE and VOUT_COMMAND command handling with 10 mV/10 ms step resolution and ±30 mV settling accuracy within 10 ms.

Key Specifications

Pinout & Package

Package: 32-lead 5 mm × 5 mm QFN with exposed pad (UH package). Thermal performance optimized for high-current DC/DC applications with junction-to-board θ_JB = 12°C/W.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-output PMBus controller applications.

Compared with LTC3883IUH, LTC3884IUH reduces integration by removing one output channel and associated telemetry path, while TPS53689RTAR trades hardware-level sequencing autonomy for vendor-specific firmware dependencies - making LTC3883IUH uniquely suited for FPGA and multi-ASIC systems demanding guaranteed timing determinism without host CPU involvement.

Availability

LTC3883IUH is available at Aetrix Electronics and suitable for FPGA power delivery, telecom baseband processing, and industrial AI accelerator modules requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing.

Supply support for LTC3883IUH 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

Analog Devices is a global leader in high-performance analog, mixed-signal, and power management semiconductors, serving industrial, automotive, communications, and computing markets since 1965.

The LTC3883IUH belongs to Analog Devices' Power System Management (PSM) product line, designed specifically to address FPGA, ASIC, and multi-core SoC power delivery challenges - emphasizing autonomous sequencing, sub-0.5% regulation, and interoperable telemetry across heterogeneous power rails.

FAQ

What is the primary function of the LTC3883IUH in an FPGA power system?

The LTC3883IUH serves as a dual-output, PMBus-enabled synchronous buck controller that regulates and sequences FPGA core and auxiliary voltage rails. It executes SmartVID2 voltage requests from the FPGA, maintains ±0.5% output accuracy over temperature and load, and coordinates timing with other PSM ICs via SHARE_CLK - ensuring deterministic power-up/down without host processor involvement. The LTC3883IUH is essential for minimizing FPGA static power while guaranteeing timing closure.

Does the LTC3883IUH support Altera Arria 10 SmartVID2 voltage scaling?

Yes, the LTC3883IUH fully supports Altera Arria 10 SmartVID2 through hardware-accelerated interpretation of PMBus VOUT_MODE and VOUT_COMMAND commands. It accepts dynamic voltage requests during boot, settles to within ±30 mV of the target in ≤10 ms, and holds the commanded voltage statically during FPGA operation - matching the 0.82 V to 0.93 V SmartVID range specified for Arria 10. This capability is built into the LTC3883IUH silicon and requires no firmware updates.

How does the LTC3883IUH achieve ±0.5% voltage accuracy?

The LTC3883IUH achieves ±0.5% output voltage accuracy through a combination of laser-trimmed internal reference, high-precision feedback amplifier with <1 µV offset, and on-chip 16-bit ADC for closed-loop calibration. This specification holds across –40°C to +125°C junction temperature, full input voltage range (4.5 V–26.5 V), and 0–100% load step - eliminating the need for external trimming resistors or post-assembly calibration. The LTC3883IUH's accuracy directly enables FPGA voltage optimization without safety margins.

Can the LTC3883IUH operate without a microcontroller or host system?

Yes, the LTC3883IUH operates autonomously after initial configuration. Its EEPROM stores all settings - including output voltages, sequencing delays, fault thresholds, and SHARE_CLK timing parameters - enabling full power-up/down sequencing, telemetry logging, and fault response without any host processor. The LTC3883IUH uses hardware-based SHARE_CLK and FAULT buses to coordinate with other PSM ICs, making it ideal for headless or safety-critical systems where microcontroller dependency is unacceptable.

What package type and thermal characteristics does the LTC3883IUH use?

The LTC3883IUH is packaged in a 32-lead 5 mm × 5 mm QFN with exposed thermal pad (UH package). It features a junction-to-board thermal resistance (θ_JB) of 12°C/W, enabling efficient heat transfer to the PCB plane. The package supports reflow soldering per JEDEC J-STD-020 and is rated for operation from –40°C to +125°C ambient. This thermal design allows the LTC3883IUH to sustain continuous 13 A per phase output current in compact, high-density FPGA power systems.