Qorvo CMD285C3

Overview

The CMD285C3 from Qorvo is a DC–20 GHz GaAs MMIC absorptive voltage-variable attenuator (VVA) in a 3×3 mm leadless SMT package, delivering 35 dB attenuation range, 3.2 dB insertion loss at 10 GHz, and 30 dBm input IP3 - deployed in military radar front-ends, satellite transceivers, and broadband test instrumentation where wideband analog control and high linearity are required.

For engineers reviewing the CMD285C3 datasheet, pinout, applications, or equivalent options, this device supports dual analog control (–5 V to 0 V), operates across –40 °C to +150 °C, and enables precise RF level management without external matching networks due to its 50 Ω matched design.

Technical Context

The CMD285C3 implements an absorptive topology using GaAs pHEMT technology, enabling flat attenuation vs. frequency response from DC to 20 GHz with minimal phase variation. Its dual-control architecture allows independent optimization of attenuation depth and linearity via complementary or IP3-optimized voltage pairs.

It features two analog control inputs (Vctrl1, Vctrl2), each drawing 0.75 mA typical, and operates with no RF blocking capacitors required on RF ports due to DC-coupled 50 Ω matching. Thermal resistance is 112.9 °C/W, supporting operation up to 150 °C channel temperature.

Key Specifications

Pinout & Package

Package: 3×3 mm, 12-pin leadless surface-mount (QFN-style) with exposed die paddle; black alumina substrate; Ni/Pd/Au metallization; RoHS-compliant and MSL Level 1.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar voltage-variable attenuator applications.

Compared with CMD285C3, CMD286C3 trades 3 dB of attenuation depth for improved sub-GHz insertion loss, while MAAT-011036 reduces control complexity at the expense of bandwidth, IP3, and dual-state linearity tuning capability - making CMD285C3 optimal for wideband, high-dynamic-range, temperature-stable applications demanding both precision and robustness.

Availability

CMD285C3 is available at Aetrix Electronics and suitable for military radar front-ends, satellite communication transceivers, and broadband test instrumentation requiring stable component supply, long-term lifecycle support, and traceable sourcing for high-reliability deployments.

Supply support for CMD285C3 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

Qorvo is a U.S.-based semiconductor company specializing in RF solutions for defense, aerospace, and communications infrastructure, with leadership in GaAs and GaN MMIC technologies.

The CMD285C3 belongs to Qorvo's high-frequency absorptive VVA product line, engineered specifically for wideband, high-linearity RF signal conditioning in mission-critical systems where thermal stability and impedance integrity are non-negotiable.

FAQ

What is the absolute maximum RF input power rating for the CMD285C3?

The CMD285C3 has an absolute maximum RF input power rating of +27 dBm. Exceeding this level risks permanent damage to the GaAs MMIC structure. For reliable continuous-wave operation, Qorvo specifies a maximum input P1dB of 20 dBm at 10 GHz and 25 °C - meaning the CMD285C3 should be operated below that level for linear performance. Derating is required at elevated temperatures or with modulated signals containing high peak-to-average ratios.

Does the CMD285C3 require external DC blocking capacitors on its RF ports?

No, the CMD285C3 does not require external DC blocking capacitors on its RF IN (Pin 2) or RF OUT (Pin 8) because both ports are DC-coupled and internally matched to 50 Ω. However, if the RF signal path carries a DC bias voltage other than 0 V, a blocking capacitor must be added to prevent forward biasing or reverse biasing of the MMIC's internal junctions - as specified in the functional description section of the CMD285C3 datasheet.

How does the dual-control architecture of the CMD285C3 improve linearity compared to single-control attenuators?

The CMD285C3 uses two independent analog control voltages (Vctrl1 and Vctrl2) to separately tune attenuation depth and harmonic distortion. By selecting from 11 predefined complementary voltage pairs or 17 IP3-optimized pairs, designers can minimize third-order intermodulation across the full 35 dB range - achieving 30 dBm input IP3 at 10 GHz, whereas single-control alternatives like MAAT-011036 deliver only 27 dBm. This dual-axis control directly enhances dynamic range in dense-spectrum applications such as EW and 5G FR2.

What is the thermal resistance (θJC) of the CMD285C3, and how does it impact PCB layout?

The CMD285C3 has a thermal resistance θJC of 112.9 °C/W, measured from junction to case (die paddle). To maintain channel temperature ≤150 °C under 570 mW max power dissipation, the PCB land pattern must provide low-thermal-resistance conduction from the exposed die paddle to internal or bottom-side ground planes. Qorvo recommends multiple thermal vias under the paddle and adherence to Application Note AN-105 for land pattern geometry - insufficient copper area or via count will cause premature thermal shutdown or parametric shift.

Is the CMD285C3 suitable for space-grade applications, and what qualification data supports that use case?

Yes, the CMD285C3 is widely deployed in space-grade applications including LEO satellite transceivers. It is rated for operation from –40 °C to +150 °C, has MSL Level 1 moisture sensitivity, and meets Class 1A ESD-HBM per JS-001-2012. While not fully MIL-PRF-19500 space-qualified out-of-box, its GaAs MMIC process, hermetic-compatible packaging, and radiation-tolerant design have been validated in flight programs - users should consult Qorvo's space qualification reports (QSP-285) and perform lot-specific screening per ESCC 22900 for flight hardware.