Analog Devices Inc. HMC174MS8ETR

Overview

HMC174MS8ETR from Analog Devices (formerly Hittite Microwave) is a GaAs MMIC SPDT transmit/receive switch for RF front-end signal routing in DC–3 GHz systems. It delivers 0.5 dB typical insertion loss at 2 GHz, +60 dBm input IP3 at 8 V bias, and supports positive CMOS/TTL-compatible control (0/+8 V). Its primary role is high-linearity T/R path selection in cellular/3G/WiMAX transceivers with LNA protection.

For engineers reviewing the HMC174MS8ETR datasheet, HMC174MS8ETR pinout, HMC174MS8ETR application, or HMC174MS8ETR equivalent, key selection criteria include its 0.5 dB insertion loss at 2 GHz, +60 dBm IIP3 at 8 V, MSOP-8 package footprint, reflective OFF-state ports, and single-supply operation from 3–10 Vdc with <500 µA quiescent current.

Technical Context

The HMC174MS8ETR implements a monolithic GaAs MMIC architecture with integrated bias control circuitry enabling single positive supply operation (3–10 Vdc) and logic-level compatible control inputs (A/B). Its RF path uses reflective SPDT topology: RFC connects to either RF1 or RF2 depending on control state, while unselected port presents a reflective short.

Switching is governed by a truth table where A=0 V/B=Vdd selects RF1, A=Vdd/B=0 V selects RF2, and both low disables both paths. RF ports are DC-coupled and require external blocking capacitors; all ground pins (6, 7) and exposed pad (pin 3, 5, 8 reference) must connect directly to PCB RF ground for optimal isolation and return loss performance.

Key Specifications

Pinout & Package

Package: MSOP-8 (3.0 × 3.0 × 0.85 mm, 14.8 mm² footprint), RoHS-compliant matte tin finish, MSL1 rated (260 °C peak reflow), low-stress molded plastic body with copper alloy leadframe. All ground leads (pins 6, 7) and RF port terminals (pins 3, 5, 8) require direct connection to PCB RF ground plane.

Key Features

Applications

Equivalent & Alternatives

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

Compared with HMC547LP3E and QM11035, the HMC174MS8ETR offers the best balance of low insertion loss (0.5 dB), high IIP3 (+60 dBm), and MSOP-8 compatibility for cost-sensitive infrastructure and portable wireless designs operating strictly within DC–3 GHz.

Availability

HMC174MS8ETR is available at Aetrix Electronics and suitable for cellular/3G infrastructure, WiMAX customer premises equipment, and automotive telematics applications requiring stable component supply, extended temperature support (-40°C to +85°C), and RoHS-compliant packaging.

Supply support for HMC174MS8ETR 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 Hittite Microwave in 2014 and integrates its high-frequency RF/Microwave portfolio into precision analog and RF solutions for communications, defense, and instrumentation.

The HMC174MS8ETR belongs to Hittite's GaAs MMIC SPDT switch product line, designed specifically for high-linearity, low-loss T/R path selection in DC–3 GHz wireless infrastructure and portable transceivers.

FAQ

What is the maximum RF input power the HMC174MS8ETR can handle before compression?

The HMC174MS8ETR delivers 36 dBm input P1dB across 0.5–3.0 GHz when biased at 8 Vdc. At 5 Vdc, P1dB drops to 32 dBm. This makes the HMC174MS8ETR suitable for medium-power repeater and base station applications where maintaining linear operation under high signal levels is essential. The HMC174MS8ETR's P1dB is voltage-scalable and specified with 0/8 V control states.

Does the HMC174MS8ETR require external blocking capacitors on its RF ports?

Yes, the HMC174MS8ETR requires external DC-blocking capacitors on RFC, RF1, and RF2 because all three RF ports are DC-coupled. Capacitor value determines the low-frequency cutoff - for example, a 100 pF capacitor sets f_low ≈ 16 MHz with 50 Ω impedance. The HMC174MS8ETR evaluation board uses 100 pF (0402) caps per RF port, confirming this design requirement.

What is the meaning of "reflective short" for the OFF-state RF ports of the HMC174MS8ETR?

A "reflective short" means that when an RF port (e.g., RF1) is disabled, it presents a near-short-circuit impedance to RF signals instead of a 50 Ω termination. This avoids 3 dB insertion loss inherent in absorptive switches and eliminates the need for external 50 Ω resistors. The HMC174MS8ETR leverages this architecture to maximize power efficiency in T/R applications where isolation is managed by system-level filtering rather than on-die termination.

Can the HMC174MS8ETR operate with 3.3 V logic control signals?

Yes - the HMC174MS8ETR supports control voltages from 0 V to Vdd, and Vdd can be set as low as 3 Vdc. When Vdd = 3.3 V, applying 0 V to pin A and 3.3 V to pin B selects RF1, satisfying standard 3.3 V CMOS logic thresholds. The HMC174MS8ETR truth table explicitly validates operation at 3 V, with control currents below 30 µA per input, ensuring compatibility with low-voltage microcontrollers.

Is the HMC174MS8ETR pin-compatible with the non-RoHS HMC174MS8 variant?

Yes - the HMC174MS8ETR and HMC174MS8 share identical MSOP-8 pinout, electrical specifications, and mechanical dimensions. The only differences are RoHS compliance (matte Sn vs. Sn/Pb finish), MSL1 reflow profile (260 °C vs. 235 °C), and package marking (H174 + 4-digit lot vs. H174 only). The HMC174MS8ETR replaces HMC174MS8 in new designs requiring lead-free assembly without layout or schematic changes.