Analog Devices Inc. DC2461A

Overview

DC2461A from Analog Devices (formerly Linear Technology) is an evaluation board for the LTC5548 microwave double-balanced passive mixer IC, supporting upconversion and downconversion in 2GHz–14GHz RF systems with DC–6GHz differential IF. It delivers 7.1dB conversion loss and +24.4dBm IIP3 at 5.8GHz, enabling high-linearity signal processing in phased-array radar and wireless backhaul transceivers.

For engineers reviewing the DC2461A datasheet, DC2461A pinout, DC2461A application, or DC2461A equivalent, this page provides verified board-level specifications, RF/IF/LO interface implementation details, thermal management guidance, and design-ready layout references per Linear's official evaluation circuit (Figure 1 & Figure 2).

Technical Context

The DC2461A implements the LTC5548's full signal path: single-ended 50Ω RF port (Pin 5), single-ended 50Ω LO port (Pin 11), and differential IF+ / IF– ports (Pins 2 & 3), with on-board 0.15pF shunt capacitors placed at precise 1.4mm (RF) and 3.55mm (LO) distances to maintain broadband 50Ω matching across 2–14GHz and 1–12GHz respectively.

It supports both low-side and high-side LO injection, enables/disables the integrated LO frequency doubler via X2 control (Pin 8), and provides fast turn-on/turn-off (0.2μs/0.1μs) for TDD operation - all while maintaining thermal stability via exposed-pad grounding and optimized copper pour per LTC5548's θ_JC = 25°C/W specification.

Key Specifications

Availability

DC2461A is available at Aetrix Electronics and suitable for microwave transceiver development, phased-array antenna calibration, and C/X/Ku-band radar prototyping requiring stable component supply and traceable evaluation hardware.

Supply support for DC2461A 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 maintains full technical and manufacturing continuity for all Linear RF products including the LTC5548 family.

The DC2461A belongs to Linear's precision RF evaluation board product line, designed specifically to accelerate time-to-test for high-frequency mixer applications in defense, satellite, and 5G infrastructure.

FAQ

What is the primary purpose of the DC2461A evaluation board?

The DC2461A evaluation board is a fully assembled and tested platform for characterizing the LTC5548 microwave mixer IC. It implements the recommended RF/LO/IF interface network, thermal layout, and power delivery per Linear's Figure 1 and Figure 2, enabling immediate measurement of conversion loss, IIP3, noise figure, and isolation without custom PCB design. The DC2461A itself contains no active circuitry beyond passive matching components and connectors.

Does the DC2461A support both upconversion and downconversion modes?

Yes, the DC2461A supports both upconversion and downconversion as implemented by the underlying LTC5548 IC. Its layout and component selection (including 0.15pF RF/LO shunt caps and 22pF AC-coupling caps) are optimized for either mode across the full 2–14GHz RF range and DC–6GHz IF bandwidth. Measured performance data in the LTC5548 datasheet (Figures G22–G39) confirms operation in both configurations with low-side and high-side LO injection.

How is the IF port configured on the DC2461A, and what external components are required for single-ended use?

The DC2461A exposes the LTC5548's differential IF+ and IF– pins (Pins 2 & 3) via SMA connectors. For single-ended IF operation, an external 1:1 balun such as the Mini Circuits TC1-1-13M+ (4.5MHz–3GHz) or TCM1-83X+ (10MHz–6GHz) must be used. The board does not integrate a balun; its IF traces are routed differentially with 100Ω characteristic impedance to preserve signal integrity before external conversion.

What is the role of the 0.15pF capacitors on the DC2461A, and why are their placement distances critical?

The two 0.15pF capacitors on the DC2461A serve as broadband matching elements: one placed 1.4mm from the RF pin (Pin 5) and another 3.55mm from the LO pin (Pin 11). These precise distances establish controlled transmission-line stubs that transform the LTC5548's intrinsic port impedances to 50Ω across 2–14GHz (RF) and 1–12GHz (LO), as validated in Figures F04a/b and F06a/b of the datasheet. Deviating from these lengths degrades return loss.

Can the DC2461A be used for DC-coupled IF applications, and what precautions apply?

Yes, the DC2461A supports true DC-coupled IF operation because the LTC5548 IF port is specified from DC to 6GHz. However, the board's differential IF outputs (Pins 2 & 3) include ESD protection diodes referenced to ground, so DC biasing must respect the ±0.3V absolute maximum input voltage rating. No series blocking capacitors are installed on the IF path - users must add external DC-blocking or bias-tee networks only if required by downstream circuitry.