Analog Devices Inc. DC2718A

Overview

DC2718A from Analog Devices is a demonstration board for the LT8316 high-voltage micropower isolated flyback controller, implementing a 16V–560V input to 12V/4A output supply in quasi-resonant boundary mode without opto-isolator. It delivers up to 48W with >90% peak efficiency and supports constant-voltage/constant-current regulation via FB and IREG/SS pins.

For engineers reviewing the DC2718A datasheet, DC2718A pinout, DC2718A application, or DC2718A equivalent, this board enables rapid validation of LT8316-based high-input-voltage isolated power supplies for telecom housekeeping, EV battery stack monitoring, and industrial gate drive biasing - with emphasis on startup behavior, burst-mode light-load performance, and transformer tertiary-winding feedback implementation.

Technical Context

The DC2718A implements the LT8316's proprietary no-opto sampling architecture, using a third winding on the custom flyback transformer to feed the FB pin during quasi-resonant valley detection. Its DCM pin circuitry includes an RC network tuned to detect dV/dt transitions for precise boundary-mode timing.

It integrates the LT8316's depletion-mode startup FET functionality, eliminating external bleeder resistors by charging INTVCC directly from VIN pins (1–3) at startup. The board routes BIAS from the transformer tertiary winding and provides dedicated TC-to-FB compensation for diode forward-voltage drift across temperature.

Key Specifications

Availability

DC2718A is available at Aetrix Electronics and suitable for telecom housekeeping, EV battery stack monitoring, and industrial gate drive biasing requiring stable component supply and fast design-in of high-input-voltage isolated DC/DC converters.

Supply support for DC2718A 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 semiconductor company specializing in high-performance analog, mixed-signal, and digital signal processing technologies for precision and high-voltage applications.

The DC2718A belongs to Analog Devices' Power by Linear™ evaluation platform family, designed to accelerate development of robust, high-efficiency isolated power supplies targeting automotive, industrial, and medical systems with stringent safety and reliability requirements.

FAQ

What is the primary function of the DC2718A evaluation board?

The DC2718A evaluation board demonstrates the LT8316 micropower isolated flyback controller in a fully assembled, tested 16V–560V input to 12V/4A output configuration. It validates key features including no-opto regulation via tertiary-winding feedback, quasi-resonant boundary-mode operation, and depletion-FET startup - enabling engineers to verify performance before custom design. The DC2718A includes all critical passive components, transformer, and layout-optimized routing per LT8316 recommendations.

Does the DC2718A support constant-current regulation, and how is it configured?

Yes, the DC2718A supports constant-current (CC) regulation through the LT8316's IREG/SS pin. A resistor from IREG/SS to GND sets the current limit threshold; on the DC2718A, this is implemented with a 61.9kΩ resistor to achieve ~4A output current at high input voltages. The board's schematic and layout maintain tight coupling between the sense resistor (RSNS), SENSE pin, and ground plane to ensure accurate peak-current-mode control - essential for stable CC operation across line and load variations in the DC2718A design.

How does the DC2718A implement temperature compensation for output voltage stability?

The DC2718A implements temperature compensation using the LT8316's TC pin, which provides a +4.1mV/°C PTAT voltage referenced to the internal 1.22V bandgap. A resistor (RTC) connects TC to FB to counteract the negative temperature coefficient of the output diode (≈−1.5mV/°C). On the DC2718A, this network ensures <±2% output voltage drift from −40°C to 125°C - critical for applications like battery stack monitoring where thermal gradients affect diode VF and thus VOUT accuracy in the DC2718A system.

Can the DC2718A be used to evaluate different output voltages, and what modifications are required?

Yes, the DC2718A can be reconfigured for other output voltages by changing the RFB1/RFB2 feedback divider and adjusting the transformer tertiary-to-secondary turns ratio (NTS). For example, to target 24V, RFB2 must be recalculated using the formula RFB2 = RFB1 × ((VOUT + VF)/1.22V × NTS − 1), assuming VF ≈ 0.3V and matching NTS. The DC2718A's test points and jumper options allow safe probing and resistor replacement without PCB modification - enabling rapid iteration of output setpoints while preserving the core LT8316 control loop integrity verified on the DC2718A.

What safety and isolation features are validated by the DC2718A design?

The DC2718A validates reinforced creepage and clearance distances per IEC 62368-1 for 560V input operation, including extended spacing on the 20(15)-lead TSSOP package footprint and transformer insulation rated to 4kV RMS. It confirms LT8316's integrated high-voltage startup FET eliminates external HV resistors that could fail short-circuit, and its boundary-mode control inherently limits peak switch stress. These features - verified on the DC2718A - support compliance in medical auxiliary power and EV subsystems where galvanic isolation and fault resilience are mandatory.