Analog Devices Inc. 105143-HMC284MS8G

Overview

HMC284MS8G from Hittite Microwave Corporation is a non-reflective SPDT RF switch IC designed for signal path selection in DC–3.5 GHz systems, featuring 0.7 dB typical insertion loss at 3.5 GHz, >45 dB isolation at 2.0 GHz, and positive 0/+5 V control logic compatible with CMOS/TTL. It serves in cellular/PCS base station transmit/receive switching paths where low distortion and high off-state return loss are critical.

For engineers reviewing the HMC284MS8G datasheet, HMC284MS8G pinout, HMC284MS8G application, or HMC284MS8G equivalent, key selection criteria include non-reflective OFF-state behavior, 40 ns RF rise/fall time, +26 dBm absolute maximum RF input power, and MSOP8G package thermal resistance of 140 °C/W on the insertion loss path.

Technical Context

This monolithic GaAs pHEMT SPDT switch integrates on-chip termination for both RF1 and RF2 ports in the OFF state, enabling true non-reflective operation without external 50 Ω resistors. Its control architecture uses complementary A/B inputs (0/+5 V) to select RFC→RF1 or RFC→RF2 paths while maintaining <25 µA control current per input.

The device operates over –40 °C to +85 °C with ESD sensitivity rated Class 1A (HBM), and requires DC blocking capacitors at all RF ports. Thermal management mandates soldering the exposed paddle and all ground leads directly to PCB RF ground to achieve specified 140 °C/W (insertion) and 190 °C/W (terminated) thermal resistance.

Key Specifications

Pinout & Package

Package: MSOP8G (8-lead grounded base MSOP), low-stress injection-molded plastic body, Sn/Pb lead finish, MSL1 rating, 235 °C peak reflow.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar SPDT switch applications.

Compared with HMC194MS8 and QM11036, the HMC284MS8G uniquely delivers verified non-reflective OFF-state behavior within its 3.5 GHz band, making it the only option among the three that eliminates external termination components while maintaining +18 dBm hot-switch rating and 40 ns switching speed.

Availability

HMC284MS8G is available at Aetrix Electronics and suitable for cellular base stations, 2.4 GHz ISM equipment, and 3.5 GHz wireless local loop infrastructure requiring stable component supply, consistent RF performance, and long-term manufacturability.

Supply support for HMC284MS8G 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

Hittite Microwave Corporation was a U.S.-based RF/microwave semiconductor company specializing in high-performance analog and mixed-signal ICs for wireless infrastructure, defense, and test equipment before its acquisition by Analog Devices in 2014.

The HMC284MS8G belongs to Hittite's high-isolation SPDT switch product line, engineered specifically for non-reflective signal routing in FDD/TDD base station transceivers and point-to-point radios operating up to 3.5 GHz.

FAQ

What is the maximum RF input power the HMC284MS8G can handle continuously?

The HMC284MS8G supports +18 dBm continuous RF input power during hot switching (Vctl = 0/+5 V), and +26 dBm as absolute maximum RF input power under static conditions. Exceeding +18 dBm during switching may cause reliability degradation. Always observe the 1 dB compression limit-24 dBm at 3.5 GHz-as defined in the electrical specifications. Derating is recommended for operation above +85 °C ambient.

Does the HMC284MS8G require external termination resistors on RF1 and RF2?

No, the HMC284MS8G does not require external termination resistors on RF1 or RF2. Its non-reflective design integrates internal 50 Ω terminations for both OFF-state ports, ensuring >10 dB return loss from 0.5–3.5 GHz without added components. This eliminates layout complexity and parasitic effects associated with discrete resistors, preserving high isolation and broadband match.

What is the recommended PCB grounding strategy for the HMC284MS8G?

The HMC284MS8G requires all ground pins (3,6,7,8) and the exposed paddle to be soldered directly to a solid, low-inductance RF ground plane. A grounded coplanar waveguide layout is recommended, with continuous ground under the component and between RFC, RF1, and RF2 traces. Failure to fully connect the paddle results in degraded isolation (>10 dB loss) and increased thermal resistance beyond the specified 140 °C/W.

Can the HMC284MS8G be driven directly by standard CMOS logic?

Yes, the HMC284MS8G control inputs A and B accept 0/+5 V logic levels and draw only ±25 µA, making them directly compatible with HC-series CMOS gates powered at +5 V. No level-shifting or buffering is required. However, ensure control voltage tolerances remain within ±0.2 Vdc, and avoid floating inputs-tie unused controls to Vdd or GND via 10 kΩ resistors to prevent unintended switching.

What is the thermal resistance of the HMC284MS8G and how does it affect power handling?

The HMC284MS8G has a thermal resistance of 140 °C/W on the insertion loss path and 190 °C/W on the terminated path. These values assume full soldering of the exposed paddle and all ground leads to a 4-layer PCB with ≥2 oz copper ground plane. Higher thermal resistance increases junction temperature under RF load, potentially reducing reliability and compression performance-especially critical when operating near +26 dBm absolute maximum ratings.