Analog Devices Inc. DC899A

Overview

DC899A from Analog Devices (formerly Linear Technology) is a 2-phase dual-output synchronous buck demonstration board centered on the LTC3728LXCUH controller IC. It delivers regulated 2.5V/5A and 3.3V/5A outputs from a 4.5V–13.2V input, features external clock synchronization, integrated 5V bias LDO, and thermal-enhanced 5 mm × 5 mm QFN package with exposed pad.

For engineers reviewing the DC899A datasheet, DC899A pinout, DC899A application, or DC899A equivalent, key selection considerations include dual-output phase interleaving, ±2% output voltage accuracy across full load, 400 kHz fixed switching frequency, high-efficiency operation (up to 91% at 3.3V/5A), and compact drop-in power stage layout (0.85″ × 0.85″).

Technical Context

The DC899A implements a two-phase interleaved synchronous buck topology using the LTC3728LXCUH, enabling current sharing between phases to reduce input/output ripple and improve transient response. Each output is independently regulated with dedicated RUN/SS pins and feedback resistors, supporting independent enable, soft-start, and overcurrent protection.

It operates with an integrated 5V bias LDO for gate driver supply, supports external clock synchronization up to 1 MHz, and maintains stable regulation across 0–5A per rail under 4.5V–13.2V input-within the LTC3728LXCUH's 30V absolute maximum input rating.

Key Specifications

Availability

DC899A is available at Aetrix Electronics and suitable for industrial embedded power validation, FPGA/ASIC multi-rail evaluation, and telecom/datacom intermediate bus testing requiring stable component supply and rapid prototyping capability.

Supply support for DC899A 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 acquired Linear Technology in 2017 and continues its legacy of high-performance analog, power management, and mixed-signal ICs for precision and power-critical applications.

The DC899A belongs to Linear's demonstration circuit (DC) series, designed to accelerate evaluation of their power controllers-specifically showcasing multi-phase, dual-output synchronous buck architectures for complex digital system power delivery.

FAQ

What is the primary function of the DC899A demonstration board?

The DC899A demonstration board is a fully assembled and tested 2-phase dual-output synchronous buck power supply reference design. It showcases the LTC3728LXCUH controller IC in action, delivering regulated 2.5V/5A and 3.3V/5A outputs from a 4.5V–13.2V input. The DC899A enables rapid validation of efficiency, transient response, thermal performance, and layout best practices for multi-rail power systems before custom design.

Does the DC899A support external clock synchronization?

Yes, the DC899A supports external clock synchronization via the SYNC pin of the LTC3728LXCUH controller. This allows precise timing alignment with system clocks or other power stages to reduce beat frequencies and improve EMI performance. The DC899A schematic includes the necessary termination and coupling components to accept an external clock signal up to 1 MHz.

What are the input voltage limits for safe operation of the DC899A?

The DC899A is designed for 4.5V–13.2V input operation, with an absolute maximum input rating of 15V as specified in the quick start guide. Exceeding 15V risks damage to the LTC3728LXCUH and associated MOSFETs. Although the underlying LTC3728LXCUH IC supports up to 30V, the DC899A board's component selection-including input capacitors and FETs-is optimized for ≤15V operation.

Can the DC899A be used to evaluate both outputs simultaneously under full load?

Yes, the DC899A is rated for simultaneous full-load operation: 5A on VOUT1 (2.5V) and 5A on VOUT2 (3.3V), with measured efficiencies of 89% and 91% respectively at 12V input. Thermal performance remains within safe limits due to the exposed-pad QFN package of the LTC3728LXCUH and optimized top-side power stage layout, verified in the published efficiency curves (Figures 3 and 4).

Where can I obtain design files for the DC899A?

Design files-including schematic, layout Gerbers, and bill of materials-for the DC899A are available directly from Analog Devices. As noted in the Quick Start Guide, users should contact the LTC factory (now part of Analog Devices' Power by Linear team) to request these files. They are not publicly hosted but are provided upon request for engineering evaluation and derivative design purposes.