Analog Devices Inc. 110409-HMC452ST89

Overview

HMC452ST89 from Analog Devices (formerly Hittite Microwave) is a GaAs InGaP HBT 1 W MMIC power amplifier operating from 0.4 to 2.2 GHz in an SOT-89 package. It delivers 21 dB gain at 400 MHz, +49 dBm output IP3 at 2.1 GHz, 50% PAE at +31 dBm Pout, and supports CDMA2000 channel power of +25 dBm at –45 dBc ACP - ideal for cellular base station driver stages and fixed wireless front-ends.

For engineers reviewing the HMC452ST89 datasheet, HMC452ST89 pinout, HMC452ST89 application, or HMC452ST89 equivalent, key selection criteria include its broadband 0.4–2.2 GHz operation, single +5 V supply requirement, SOT-89 thermal performance (24.1 °C/W), and verified RF linearity across GSM, W-CDMA, and CDMA2000 bands.

Technical Context

The HMC452ST89 integrates a two-stage InGaP HBT amplifier with DC-coupled input and RF/DC-biased output. Its internal bias network enables stable operation from –40 °C to +85 °C with <0.02 dB/°C gain variation, and it achieves >11 dB output return loss across all bands without external feedback.

Designed for minimal external component count, the device uses off-chip matching networks (e.g., 47 nH/40 nH inductors and 12 pF/15 pF capacitors) to optimize gain flatness and IP3 across frequency bands - confirmed via measured data at 400 MHz, 900 MHz, 1900 MHz, and 2100 MHz.

Key Specifications

Pinout & Package

SOT-89 package with exposed ground paddle; requires soldering of pins 2 and 4 plus bottom paddle to RF/DC ground per MSL1 reflow profile (235 °C peak). Thermal resistance is 24.1 °C/W junction-to-paddle.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar RF power amplifier applications.

Compared with QPL9057 and SKY65167-360LF, the HMC452ST89 offers highest OIP3 (+49 dBm) and widest low-end bandwidth (down to 400 MHz), making it optimal for multi-band FWA and legacy cellular infrastructure where linearity at sub-1 GHz frequencies is essential.

Availability

HMC452ST89 is available at Aetrix Electronics and suitable for GSM/EDGE base station drivers, CDMA2000 mobile infrastructure, and fixed wireless access CPE requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for HMC452ST89 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 maintains its high-frequency RF product portfolio, specializing in microwave/mmWave ICs for defense, communications, and instrumentation.

The HMC452ST89 belongs to Hittite's legacy GaAs MMIC power amplifier family, designed specifically for broadband, high-linearity driver applications in cellular infrastructure and fixed wireless systems.

FAQ

What is the absolute maximum RF input power rating for the HMC452ST89?

The HMC452ST89 has an absolute maximum RF input power rating of +31 dBm at +5 Vdc supply, as specified in the Absolute Maximum Ratings table. Exceeding this level risks permanent damage to the InGaP HBT transistor junctions, especially under mismatched load conditions. Operation should remain within the linear region using recommended application circuits.

Does the HMC452ST89 require external DC blocking capacitors on RFIN and RFOUT?

Yes, the HMC452ST89 requires external DC blocking capacitors on both RFIN (Pin 1) and RFOUT (Pin 3). The input is DC-coupled but expects external AC coupling (e.g., 12 pF at 400 MHz), and the output serves as both RF path and DC bias injection point - necessitating series blocking (e.g., 39 pF) before downstream filtering or antenna interface.

Can the HMC452ST89 operate stably at +85 °C ambient temperature?

Yes, the HMC452ST89 is fully characterized and rated for continuous operation from –40 °C to +85 °C ambient. At +85 °C, its gain variation remains ≤0.02 dB/°C, P1dB degrades by ≤0.5 dB, and PAE stays above 45% - confirmed by thermal testing with proper ground paddle soldering and heatsinking per the datasheet layout guidelines.

What is the thermal resistance (θ_JA) of the HMC452ST89 in standard PCB mounting?

The HMC452ST89 has a junction-to-ground-paddle thermal resistance (θ_JP) of 24.1 °C/W, not θ_JA. When mounted per recommendations - including soldering pins 2 and 4 plus the exposed paddle to a multilayer PCB ground plane with ≥6 thermal vias - effective θ_JA is ~55 °C/W. This enables 1 W operation at +85 °C ambient with ≤115 °C junction temperature.

Is the HMC452ST89 pin-compatible with the HMC452ST89E variant?

Yes, the HMC452ST89 and HMC452ST89E share identical pinout, footprint, and electrical specifications. The only difference is RoHS compliance: HMC452ST89E uses 100% matte tin lead finish (MSL1, 260 °C peak reflow), while HMC452ST89 uses Sn/Pb (MSL1, 235 °C peak). Both are drop-in replacements in existing designs.