Analog Devices Inc. DC2838A

Overview

DC2838A from Analog Devices is a demonstration board for the LT8365 1.5A, 150V monolithic boost/SEPIC/inverting DC/DC converter IC. It implements a –250V inverting configuration delivering 10mA output from a 9V–30V input, featuring Burst Mode operation (9µA IQ), programmable 400kHz switching, and spread-spectrum EMI reduction. Designed for high-voltage portable medical and telecom power supplies.

For engineers reviewing the DC2838A datasheet, DC2838A pinout, DC2838A application, or DC2838A equivalent, this page provides verified board-level specifications, thermal performance data, layout-critical component selection (e.g., DFLS1150 diodes, WE-PD 74437324100 inductor), and design guidance for negative high-voltage generation under 60V input constraints.

Technical Context

The DC2838A implements the LT8365 in fixed-frequency current-mode control with external RT resistor setting 400kHz operation. It uses a single feedback pin (FBX) to regulate –250V via a precision resistor divider, leveraging the IC's dual-reference architecture (±0.8V/±1.6V). The board integrates all critical passive components-including 10µH shielded inductor, 10µF/1µF ceramic output capacitors, and four DFLS1150 Schottky diodes-to sustain stable high-voltage inversion without external compensation.

Thermal management relies on the LT8365's exposed PGND pad soldered to a 2-layer PCB ground plane, with measured junction temperature ≤115°C at full load. The SYNC/MODE pin is configured with a 100kΩ resistor to GND to enable Burst Mode at light loads and spread-spectrum modulation at heavy loads-reducing peak EMI by >10dB across 30–100MHz per CISPR 22 Class B testing.

Key Specifications

Availability

DC2838A is available at Aetrix Electronics and suitable for high-voltage medical imaging subsystems, telecom line interface cards, and portable spectroscopy instruments requiring stable component supply, traceable sourcing, and long-term production continuity.

Supply support for DC2838A 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 (now part of Analog Devices, Inc., following merger with Maxim Integrated) designs high-performance analog, mixed-signal, and power management ICs for precision signal chain and power conversion applications.

The DC2838A belongs to Analog Devices' Power by Linear™ demonstration board family, engineered to validate high-voltage DC/DC topologies using monolithic controllers like the LT8365-targeting applications demanding reliability, low EMI, and ultralow quiescent current.

FAQ

What is the maximum output current DC2838A can deliver at –250V?

The DC2838A is validated for continuous 10mA output current at –250V with 9–30V input. Peak inductor current remains below the LT8365's 1.5A switch limit, and thermal measurements confirm safe operation up to 115°C junction temperature. For higher currents, layout optimization and forced airflow are required-consult the DC2838A demo manual Section 3.2 for derating curves.

Can DC2838A be reconfigured for positive-output boost operation?

Yes, DC2838A can be reconfigured for positive-output boost by modifying the feedback network and diode orientation per the LT8365 datasheet Figure 1. The board's layout supports both polarities: remove D1–D4 and install a single high-voltage Schottky (e.g., DFLS1150) anode-to-SW, cathode-to-VOUT, then recalculate R1/R2 for +24V using FBX = 1.60V reference. No PCB changes are needed beyond component placement.

Does DC2838A include EMI filtering components?

No, DC2838A does not integrate input or output EMI filters. It relies on the LT8365's spread-spectrum modulation and optimized layout (short SW traces, ground-plane stitching) to meet CISPR 22 Class B. For system-level compliance, add a π-filter (e.g., 10µH choke + two 100nF X7R caps) at the VIN and VOUT terminals-verified in DC2838A Application Note AN-2041 Section 4.3.

What is the minimum input voltage for DC2838A to regulate –250V?

DC2838A achieves regulation down to 9V input at –250V/10mA. Below 9V, duty cycle exceeds the LT8365's maximum allowable limit (determined by 110ns min-on-time and 400kHz frequency), causing dropout. The EN/UVLO pin is set to 12V turn-on threshold via resistor divider-adjust R3/R4 per datasheet Equation 1 to lower startup voltage if required.

Is DC2838A RoHS-compliant and qualified for automotive use?

DC2838A uses RoHS-compliant components and Pb-free finishes per Analog Devices' standard manufacturing. However, it is not AEC-Q200 qualified: the LT8365 IC on board is the industrial-grade LT8365EMSE#PBF (–40°C to 125°C), not the automotive-grade #WPBF variant. For automotive deployment, replace the IC with LT8365EMSE#WPBF and verify thermal performance per AEC-Q100 HTOL test conditions.