Analog Devices Inc. 117160-HMC605LP3

Overview

HMC605LP3 from Hittite Microwave Corporation (now part of Analog Devices) is a GaAs PHEMT MMIC low-noise amplifier with integrated bypass mode, operating in the 2.3–2.7 GHz band for WiMAX/WiBro receivers. It delivers 20 dB gain, 1.1 dB noise figure, +31 dBm output IP3 at +5 V/74 mA, and features 50 Ω input/output matching with no external components required.

For engineers reviewing the HMC605LP3 datasheet, HMC605LP3 pinout, HMC605LP3 application, or HMC605LP3 equivalent, key selection criteria include LNA/bypass mode switching speed (6 ns LNA→bypass), failsafe default-to-bypass behavior, and dual-supply compatibility (+3 V or +5 V) in compact 3×3 mm LP3 package.

Technical Context

The HMC605LP3 integrates a monolithic GaAs PHEMT LNA core and a low-loss passive bypass path on a single die, enabling seamless RF signal routing without external switches. Its control logic uses a single Vctl pin to select between active amplification (Vctl = Vdd + 0.3 V) and bypass (Vctl = 0 + 0.3 V), with current dropping from 74 mA to 10 μA in bypass mode.

Thermal design is supported by a ground paddle and copper-alloy leadframe (θ_JA = 63.08 °C/W); operation is specified from –40 °C to +100 °C. Absolute maximum RF input is +22 dBm in LNA mode and +30 dBm in bypass mode, with channel temperature limited to 150 °C.

Key Specifications

Pinout & Package

The HMC605LP3 is housed in a 16-lead, 3×3 mm Low Stress Injection Molded Plastic (LSIMP) package with exposed ground paddle (MSL1, Sn/Pb finish). All ground pins and the paddle must be soldered to PCB RF ground per Hittite's land pattern recommendation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar low-noise amplifier with bypass applications.

Compared with HMC605LP3E, the HMC605LP3 offers identical RF performance with Sn/Pb finish for legacy reflow processes; versus QPL9547, it provides true integrated bypass with faster switching and failsafe behavior-critical for TDD infrastructure where signal continuity is non-negotiable.

Availability

HMC605LP3 is available at Aetrix Electronics and suitable for wireless infrastructure, tower-mounted amplifiers, and fixed wireless access equipment requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for HMC605LP3 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 fabless RF semiconductor company specializing in high-performance analog and mixed-signal ICs for microwave and millimeter-wave applications, acquired by Analog Devices in 2014.

The HMC605LP3 belongs to Hittite's SMT low-noise amplifier family, designed specifically for carrier-grade wireless infrastructure requiring high linearity, ultra-low noise, and robust fail-safe operation in harsh environmental conditions.

FAQ

What is the absolute maximum RF input power for HMC605LP3 in bypass mode?

The absolute maximum RF input power for HMC605LP3 in bypass mode is +30 dBm, as specified in the Absolute Maximum Ratings table. This rating ensures protection of internal passive structures during high-power transient events such as transmit leakage or nearby interferers. Exceeding this level may cause permanent damage to the device, regardless of duty cycle or duration. The HMC605LP3 datasheet confirms this value applies specifically to bypass mode operation at Vdd = +5.0 Vdc.

Does HMC605LP3 require external matching components at RF ports?

No, HMC605LP3 does not require external matching components at its RFIN or RFOUT ports. Both ports are internally matched to 50 Ω across the 2.3–2.7 GHz band, as verified by S-parameter plots showing >13 dB input and output return loss. This eliminates the need for discrete matching networks, reducing bill-of-materials cost and PCB footprint. The HMC605LP3 application circuit confirms use of only AC-coupling capacitors (C1, C2) with no series/shunt impedances.

How does the failsafe behavior of HMC605LP3 operate without DC power applied?

When no DC power is applied to the HMC605LP3 Vdd pin, the device defaults to bypass mode due to internal circuit design - ensuring continuous RF signal path even during power loss or brownout. This behavior is explicitly stated in the General Description: "The HMC605LP3 is failsafe and will default to the bypass mode with no DC power applied." In this state, insertion loss remains at –2.0 dB typical, preserving system-level connectivity while disabling amplification.

What is the thermal resistance (θ_JA) of HMC605LP3, and how does it impact thermal design?

The thermal resistance from channel to ambient (θ_JA) for HMC605LP3 is 63.08 °C/W, measured with proper grounding of all GND pins and the exposed paddle to PCB RF ground. This value assumes standard JEDEC test conditions and dictates minimum copper area and via count needed to maintain junction temperature below 150 °C at full 74 mA supply current. The HMC605LP3 datasheet specifies derating of 15.85 mW/°C above 85 °C ambient, reinforcing the need for adequate thermal management in enclosed or high-ambient environments.

Can HMC605LP3 operate from a +3 V supply, and how does performance change versus +5 V?

Yes, HMC605LP3 is fully specified for operation from +3 V supply, delivering 20.5 dB gain and 1.3 dB noise figure (typical) at 2.5 GHz - slightly lower gain and marginally higher noise than +5 V operation (20.5 dB vs. 20.5 dB, 1.3 dB vs. 1.1 dB). Supply current drops to 28 mA at +3 V, reducing power dissipation. The HMC605LP3 datasheet includes gain and noise figure vs. Vdd curves confirming stable functionality across both voltages, enabling flexible integration into mixed-voltage systems.