Analog Devices Inc. 130784-HMC797LP5E

Overview

HMC797LP5E from Analog Devices (formerly Hittite Microwave) is a GaAs pHEMT MMIC distributed power amplifier operating from DC to 22 GHz, delivering +28 dBm P1dB output power, 13.5 dB small-signal gain, and 39 dBm output IP3 at +10 V/400 mA supply. It serves as a broadband RF driver or final-stage PA in EW, radar, and test instrumentation systems requiring wideband linear amplification.

For engineers reviewing the HMC797LP5E datasheet, HMC797LP5E pinout, HMC797LP5E application, or HMC797LP5E equivalent, key selection criteria include its 50 Ω matched I/O, 32-lead 5×5 mm QFN package, temperature-stable gain slope (±0.5 dB flatness from 12–18 GHz), and bias flexibility across +8 to +11 V drain supply.

Technical Context

The HMC797LP5E employs a distributed amplifier architecture with dual-gate GaAs pHEMT transistors enabling DC–22 GHz operation without external matching. Its internal 50 Ω input/output impedance eliminates discrete matching networks, supporting direct integration into MCMs and high-frequency PCB layouts.

It features two independent gate bias controls (Vgg1 and Vgg2): Vgg1 sets quiescent current (adjustable from –2 V to 0 V for 400 mA Idd), while Vgg2 fixes nominal gate voltage at +3.5 V. Thermal resistance is 14.6 °C/W (channel-to-paddle), with max junction temperature rated at 150 °C for 1 million-hour MTTF.

Key Specifications

Pinout & Package

Package: 32-lead, 5×5 mm leadless QFN (RoHS-compliant, MSL1, matte Sn finish). Exposed ground paddle must be soldered to PCB RF ground plane using ≥9 via holes for optimal thermal and RF performance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with HMC1099LP5E and QPA2211, the HMC797LP5E offers the best balance of wideband linearity (39 dBm IP3), compact 5×5 mm form factor, and +28 dBm output at +10 V - making it optimal for space-constrained EW and instrumentation platforms where thermal density and layout simplicity are prioritized.

Availability

HMC797LP5E is available at Aetrix Electronics and suitable for electronic warfare systems, microwave radio infrastructure, and test instrumentation requiring stable component supply, consistent RF performance across temperature, and RoHS-compliant SMT packaging.

Supply support for HMC797LP5E 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 defense, communications, and instrumentation markets.

The HMC797LP5E belongs to Hittite's legacy GaAs pHEMT MMIC amplifier product line, designed specifically for broadband, high-linearity, surface-mount RF power amplification in demanding military and test equipment applications.

FAQ

What is the recommended gate bias configuration for HMC797LP5E to achieve nominal 400 mA supply current?

The HMC797LP5E requires two gate bias voltages: Vgg2 = +3.5 V (fixed) and Vgg1 adjustable between –2 V and 0 V. To achieve 400 mA Idd at +10 V Vdd, Vgg1 must be tuned to approximately –0.8 V, as specified in the datasheet. This adjustment compensates for process variation and ensures consistent P1dB and IP3 performance across units. Always use low-inductance bypass capacitors on both Vgg1 and Vgg2 nodes to maintain stability. The HMC797LP5E datasheet includes a detailed "MMIC Amplifier Biasing Procedure" application note for implementation guidance.

Does HMC797LP5E require external matching components for 50 Ω operation?

No, the HMC797LP5E has internally matched 50 Ω input and output impedances across its full DC–22 GHz bandwidth. No external matching networks, stubs, or lumped elements are needed for basic operation. However, an external DC-blocking capacitor is required on the RFIN pin if the preceding stage is DC-coupled, and a broadband bias tee or LC network is necessary on the RFOUT/VDD pin to separate RF and DC paths. These are interface components-not matching networks-and do not alter the intrinsic 50 Ω match of the HMC797LP5E itself.

What is the maximum safe operating drain supply voltage for HMC797LP5E?

The absolute maximum drain supply voltage (Vdd) for HMC797LP5E is +12.0 V, as defined in the Absolute Maximum Ratings table. However, the device is characterized and optimized for operation at +8 V, +10 V, and +11 V. At +10 V, it delivers +28 dBm P1dB and 39 dBm IP3 with 400 mA Idd. Operating continuously at +12 V exceeds recommended conditions and risks accelerated degradation or thermal runaway. For reliable long-term operation, stay within the +8 V to +11 V range and monitor junction temperature-especially above 85 °C ambient-using the specified thermal resistance of 14.6 °C/W.

Can HMC797LP5E be used in pulsed RF applications such as radar transmitters?

Yes, the HMC797LP5E is qualified for pulsed RF operation in radar transmitters, with demonstrated performance across –40 °C to +85 °C ambient and validated reliability at 150 °C junction temperature. Its fast turn-on/turn-off response (no internal charge traps), stable gain flatness (±0.5 dB from 12–18 GHz), and robust 50 Ω match minimize pulse distortion and amplitude ripple. For pulsed use, ensure gate bias networks provide adequate transient suppression, and verify thermal design accommodates peak power dissipation-particularly given its 4.5 W continuous Pdiss rating at 85 °C. The HMC797LP5E evaluation board (127135) supports pulsed characterization.

Is the HMC797LP5E pinout compatible with other Hittite 5×5 mm QFN amplifiers like HMC798LP5E?

No, the HMC797LP5E pinout is not compatible with HMC798LP5E or other members of the LP5E series. While all share the same 32-lead 5×5 mm QFN outline, pin functions differ significantly: HMC797LP5E uses pin 21 for combined RFOUT/VDD, whereas HMC798LP5E separates RFOUT and VDD onto distinct pins. Additionally, ACG pin assignments and N/C locations vary. PCB layout must be designed specifically for the HMC797LP5E pin map shown in the datasheet (page 9-8); attempting to reuse footprints from other LP5E devices will result in functional failure or damage.