Analog Devices Inc. DC2846A

Overview

DC2846A from Analog Devices is a demonstration circuit for the LTC7804 low IQ synchronous boost controller in MSE package, configured as a 24V/6A DC/DC synchronous boost converter with 500kHz fixed-frequency or spread-spectrum operation, wide 6V–24V input range, and support for pulse-skipping, Burst Mode®, and forced CCM - used for evaluating high-efficiency step-up power supplies in telecom and PoE applications.

For engineers reviewing the DC2846A datasheet, DC2846A pinout, DC2846A application, or DC2846A equivalent, this board enables rapid validation of LTC7804-based boost designs under real-world load, EMI, and biasing conditions - including EXTVCC bias selection, SYNC clock injection, and VIN > VOUT topology optimization.

Technical Context

The DC2846A implements the LTC7804's current-mode control architecture with dual MOSFET drive (Q1/Q4: Infineon BSC032N04LS), integrated gate drivers, and programmable operating modes via jumpers JP1 (MODE) and JP4 (FREQSET). It supports three biasing schemes: VIN, VOUT, or external EXTVCC supply.

Its switching frequency is factory-set to 500kHz but adjustable from 100kHz to 3MHz; spread-spectrum mode reduces peak EMI by ±15% frequency dithering. When VIN exceeds VOUT, the top MOSFET remains continuously on to eliminate typical boost conduction losses.

Key Specifications

Availability

DC2846A is available at Aetrix Electronics and suitable for telecom power systems, Power over Ethernet (PoE) midspans, and automotive infotainment subsystems requiring stable component supply, fast evaluation turnaround, and verified reference design fidelity.

Supply support for DC2846A 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, Inc. is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, headquartered in Norwood, MA.

The DC2846A belongs to Analog Devices' demonstration circuit product line - purpose-built to accelerate adoption of their power management ICs, with fully validated schematics, layout, BOM, and test data for immediate engineering evaluation.

FAQ

What is the primary function of the DC2846A?

The DC2846A is a fully assembled and tested demonstration circuit for the LTC7804 synchronous boost controller. Its primary function is to provide a turnkey platform for evaluating 24V/6A step-up conversion performance - including efficiency, transient response, EMI behavior, and mode switching - under real-world input voltage and load conditions. The DC2846A itself is not an IC but a functional hardware reference design.

Does the DC2846A support synchronization to an external clock?

Yes, the DC2846A supports external clock synchronization via the SYNC terminal (E6). When jumper FREQSET (JP4) is placed in the SYNC position, the LTC7804 inside the DC2846A locks its switching frequency to an externally applied clock signal within the 100kHz–3MHz range. This capability allows precise timing alignment with system clocks or noise-sensitive sub-systems, and is fully implemented and tested on the DC2846A board.

How does the DC2846A handle input voltages higher than the output voltage?

When VIN > VOUT, the DC2846A leverages the LTC7804's topology-optimized control logic to keep the top MOSFET (Q1) continuously on, effectively bypassing the boost stage and operating in direct-conduction mode. This eliminates switching and conduction losses associated with conventional boost operation, improving efficiency and reducing heat generation - a documented feature confirmed in the DC2846A demo manual's PERFORMANCE SUMMARY section.

What are the supported operating modes on the DC2846A?

The DC2846A supports three distinct light-load operating modes selectable via jumper JP1: Pulse-Skipping Mode (PSM), Forced Continuous Conduction Mode (CCM), and low-ripple Burst Mode®. Each mode is hardware-configurable and validated - PSM improves light-load efficiency, CCM ensures constant frequency for EMI filtering, and Burst Mode® minimizes output ripple while maintaining ultra-low quiescent current. All modes are accessible and tested on the DC2846A.

Can the DC2846A be biased from the output rail?

Yes, the DC2846A supports VOUT-based biasing via jumper VBIAS (JP3), which connects the LTC7804's INTVCC regulator input to the 24V output rail. This configuration improves efficiency when the input voltage is significantly lower than the output, and is explicitly documented in the DC2846A demo manual's "Biasing Options" section. The board also supports VIN and EXTVCC biasing paths.