Analog Devices Inc. DC933A

Overview

DC933A from Analog Devices (formerly Linear Technology) is a demonstration circuit for the LT5512 active double-balanced downconverting mixer IC, optimized for HF/VHF/UHF RF-to-IF conversion at 140MHz RF / 10MHz IF with high-side LO injection. It delivers 2dB conversion gain, 20.7dBm IIP3, and 10.3dB SSB noise figure under 5V/56mA operation, enabling evaluation of high-linearity signal mixing in RF front-ends.

For engineers reviewing the DC933A datasheet, DC933A pinout, DC933A application, or DC933A equivalent, this board supports rapid validation of LT5512 performance in receiver architectures requiring wideband RF input (100–195MHz), robust LO-RF isolation (>61dB), low LO drive (-5dBm), and sub-100MHz IF output with minimal external matching.

Technical Context

The DC933A implements the LT5512 as a fully assembled, SMA-connected evaluation platform with externally matched 50Ω RF and IF ports, differential LO input, and integrated enable control. Its layout preserves the IC's internal bias architecture and eliminates precision external resistors via on-chip bias circuits.

It supports configurable RF frequency tuning from 250kHz to 450MHz and IF output from 0.1MHz to 100MHz through discrete component swaps. The board uses high-side LO injection (e.g., 150MHz LO for 140MHz RF → 10MHz IF) and maintains >10dB return loss across RF (100–195MHz), LO (up to 1.5GHz), and IF (0.5–95MHz) bands.

Key Specifications

Availability

DC933A is available at Aetrix Electronics and suitable for RF receiver development, spectrum analyzer front-end prototyping, and wireless test equipment design requiring stable component supply, traceable sourcing, and documented evaluation board performance.

Supply support for DC933A 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 designs high-performance analog, mixed-signal, and RF ICs for precision signal processing, power management, and connectivity applications across industrial, communications, and automotive markets.

The DC933A belongs to Analog Devices' demonstration circuit portfolio for RF signal chain components, developed to accelerate validation of mixer, filter, and amplifier ICs in real-world RF system designs.

FAQ

What is the primary function of the DC933A demonstration circuit?

The DC933A demonstration circuit implements the LT5512 active double-balanced downconverting mixer IC to enable rapid evaluation of RF-to-IF signal translation. It provides fully assembled SMA interfaces, calibrated biasing, and verified matching networks so engineers can measure conversion gain, IIP3, noise figure, and isolation without custom PCB design. The DC933A is not a production component but a validated reference for integrating the LT5512 into receiver front-ends.

Can the DC933A operate outside its optimized 140MHz RF / 10MHz IF configuration?

Yes - the DC933A supports reconfiguration for RF frequencies from 250kHz to 450MHz and IF outputs from 0.1MHz to 100MHz via discrete component changes per the Quick Start Guide. Its externally matched RF and IF ports maintain >10dB return loss across 100–195MHz (RF), up to 1.5GHz (LO), and 0.5–95MHz (IF), allowing flexible reuse in diverse downconversion scenarios beyond the nominal 140MHz/10MHz point.

What power supply requirements does the DC933A have?

The DC933A requires a single 4.5V to 5.25V DC supply delivering ≥100mA, with absolute maximum rating of 5.5V. Supply current is 56mA when enabled and drops to ≤100µA in shutdown mode via the EN pin. Proper sequencing is critical: VCC must be applied before EN, and EN voltage must never exceed VCC + 0.3V. The DC933A includes onboard decoupling and does not require external regulators.

How is LO drive handled on the DC933A, and what are the input limits?

The DC933A accepts single-ended or differential LO drive at its J2 SMA connector, with a robust resistive match supporting frequencies up to 1.5GHz. The LT5512's integrated LO buffer allows operation with as little as -5dBm LO power (typical), and the absolute maximum differential LO voltage is ±1.5V (+6dBm equivalent). Exceeding this risks permanent damage; users must ensure signal generator harmonics are suppressed using filters or attenuators per the test setup guidelines.

Does the DC933A include provisions for enabling or disabling the LT5512?

Yes - the DC933A exposes the LT5512's EN (enable) pin on its header, allowing full power-down control. Connecting EN to VCC (via jumper, as in the Quick Start Procedure) activates the mixer; pulling EN low disables it, reducing supply current to ≤100µA. This feature supports low-power modes in battery-operated receivers and enables precise timing of mixer activation during system-level signal acquisition sequences on the DC933A.