Analog Devices Inc. DC1821B

Overview

DC1821B from Analog Devices is an evaluation board for the LTC3114-1, a 40V, 1A synchronous buck-boost DC/DC converter with programmable average output current. It supports input voltages from 2.2V to 40V and output voltages from 2.7V to 40V, delivers up to 96% efficiency in PWM mode, operates at 1.2MHz fixed frequency, and enables accurate current regulation via external PROG resistor - used for high-power LED driver, solar battery charging, and automotive power systems.

For engineers reviewing the DC1821B datasheet, DC1821B pinout, DC1821B application, or DC1821B equivalent, this page provides verified board-level specifications, thermal performance data, supported LTC3114-1 variants (including DFN and TSSOP packages), layout-critical component placement guidance, and confirmed compatibility with 3mm × 5mm DFN-packaged LTC3114-1 devices.

Technical Context

The DC1821B implements the full LTC3114-1 reference design with single-inductor buck-boost topology, integrated 250mΩ N-channel DMOS switches, and dual bootstrap networks (BST1/BST2) supporting seamless mode transitions across VIN < VOUT, VIN > VOUT, and VIN ≈ VOUT. It validates the IC's current-mode control loop, 1.2MHz ultralow-noise PWM operation, and programmable average output current function using RPROG and CPROG on the PROG pin.

This board demonstrates the LTC3114-1's AEC-Q100-qualified operation in automotive environments, including thermal management via exposed PGND pad soldering, LDO/PLDO rail decoupling (4.7µF + 10µF), and precise RUN pin UVLO threshold setting (1.205V typical) - all implemented per Analog Devices' recommended PCB layout guidelines.

Key Specifications

Availability

DC1821B is available at Aetrix Electronics and suitable for high-reliability power system development, automotive ECU prototyping, and industrial solar charge controller validation requiring stable component supply and documented reference design fidelity.

Supply support for DC1821B 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, serving precision instrumentation, industrial automation, communications, and automotive markets.

The DC1821B belongs to Analog Devices' Power by Linear™ evaluation board family, designed specifically to accelerate robust implementation of wide-input-range buck-boost converters in noise-sensitive, thermally constrained, and safety-critical applications.

FAQ

What is the primary purpose of the DC1821B evaluation board?

The DC1821B evaluation board is a fully assembled and tested platform for the LTC3114-1 synchronous buck-boost DC/DC converter. It enables rapid validation of the IC's key features - including wide 2.2V–40V input/output capability, programmable average output current, 1.2MHz low-noise PWM operation, and seamless buck/boost transitions - under real-world thermal and load conditions. Engineers use DC1821B to verify schematics, optimize PCB layout, and characterize efficiency before final system integration.

Which LTC3114-1 variants are compatible with the DC1821B?

The DC1821B is designed for the 16-lead 3mm × 5mm DFN (DHC) package variant of the LTC3114-1, including LTC3114EDHC-1#PBF, LTC3114IDHC-1#PBF, LTC3114HDHC-1#PBF, and automotive-grade versions with #WPBF suffix. It is not compatible with the TSSOP (FE) package due to mechanical and thermal interface differences - the board's exposed pad footprint and thermal vias match only the DFN outline and PGND pad configuration.

Does the DC1821B support AEC-Q100-compliant testing?

Yes - the DC1821B implements the exact layout, component selection, and thermal interface specified in Analog Devices' AEC-Q100 qualification report for LTC3114-1 automotive variants. It supports junction temperature monitoring via the exposed PGND pad, includes recommended LDO/PLDO decoupling (4.7µF + 10µF), and validates RUN pin UVLO hysteresis (140mV) and PROG current accuracy (±5%) across –40°C to 125°C ambient, meeting requirements for Grade 1 automotive applications.

How is output current programmed on the DC1821B?

Output current is programmed on the DC1821B using the PROG pin circuit: a resistor (e.g., 27.4kΩ for 1A) and capacitor (33nF) connect PROG to GND, generating a voltage proportional to switch D current. The board implements the formula RPROG = 1V × 25000 / IOUT(A), with PROG current gain fixed at 40µA/A. This enables accurate average current regulation independent of operating mode (buck or boost), validated down to 2V VOUT per LTC3114-1 datasheet Section 11.

Can the DC1821B be used for both Burst Mode and PWM operation?

Yes - the DC1821B includes a MODE pin jumper that allows direct selection between Burst Mode (for ultra-low quiescent current ≤30µA at light loads) and continuous PWM mode (1.2MHz fixed frequency, lower output ripple). When MODE is pulled low, the board automatically transitions to PWM mode above ~300mA load, as confirmed by efficiency curves in the LTC3114-1 datasheet Figure G02. All necessary gate drive components (BST1/BST2 capacitors, SW1/SW2 routing) support both modes without modification.