Analog Devices Inc. HMC939ATCPZ-EP-R7

Overview

HMC939ATCPZ-EP-R7 from Analog Devices is a GaAs 5-bit digital RF attenuator operating from 0.1 GHz to 33 GHz with 1 dB LSB resolution, ±0.5 dB attenuation accuracy, and 24 dBm typical P0.1dB input linearity - deployed in military radar front-ends and broadband test instrumentation requiring high-frequency precision control.

For engineers reviewing the HMC939ATCPZ-EP-R7 datasheet, HMC939ATCPZ-EP-R7 pinout, HMC939ATCPZ-EP-R7 application, or HMC939ATCPZ-EP-R7 equivalent, key selection criteria include insertion loss vs. frequency (6 dB typ. at 33 GHz), dual ±5 V supply operation, CMOS/TTL-compatible parallel interface, and −55°C to +125°C military temperature range compliance.

Technical Context

The HMC939ATCPZ-EP-R7 integrates on-chip CMOS/TTL drivers for direct parallel control of five attenuation bits (P0–P4), enabling discrete 1 dB steps across 0–31 dB range without external level-shifting. Its GaAs process delivers stable RF performance up to 33 GHz with minimal phase variation (≤80° max relative phase shift).

It operates with dual supplies (VDD = +5 V, VSS = −5 V), supports dc-coupled 50 Ω RF ports (RF1/RF2), and requires grounded exposed pad for thermal and electrical integrity. All NIC pins are unconnected internally but tied to ground on evaluation boards per measurement conditions.

Key Specifications

Pinout & Package

Package: 24-lead Lead Frame Chip Scale Package (LFCSP), 4 mm × 4 mm body, 0.85 mm height, RoHS-compliant, with exposed thermal pad requiring solder connection to PCB ground plane.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar digital RF attenuator applications.

Compared with HMC939ALP4E and HMC624LP4E, the HMC939ATCPZ-EP-R7 uniquely combines 33 GHz bandwidth, 31 dB range, military temperature rating, and AQEC qualification - making it the only option for Ka-band radar and hardened EW platforms requiring guaranteed performance under extreme environmental stress.

Availability

HMC939ATCPZ-EP-R7 is available at Aetrix Electronics and suitable for radar front-ends, satellite communications terminals, and electronic warfare systems requiring stable component supply across extended temperature and long product lifecycles.

Supply support for HMC939ATCPZ-EP-R7 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 is a global leader in high-performance analog, mixed-signal, and RF ICs, serving precision instrumentation, communications, and defense markets since 1965.

The HMC939ATCPZ-EP-R7 belongs to Analog Devices' Hittite Microwave RFIC product line, engineered specifically for broadband defense, aerospace, and test equipment applications demanding millimeter-wave accuracy and ruggedized reliability.

FAQ

What is the absolute maximum RF input power rating for the HMC939ATCPZ-EP-R7?

The HMC939ATCPZ-EP-R7 has an absolute maximum RF input power rating of 27 dBm across 0.1 GHz to 33 GHz at TCASE = 85°C. This limit applies regardless of attenuation state and must not be exceeded to avoid permanent damage. Derated power dissipation curves are provided in the datasheet for operation above 85°C case temperature.

Does the HMC939ATCPZ-EP-R7 require external dc blocking capacitors on RF1 and RF2?

No, the HMC939ATCPZ-EP-R7 features dc-coupled RF ports. RF1 and RF2 are internally biased to 0 V dc and impedance-matched to 50 Ω, so external dc blocking capacitors are unnecessary when the connected RF line operates at 0 V dc potential - simplifying layout in transceiver signal chains.

How is the exposed pad (EPAD) of the HMC939ATCPZ-EP-R7 used in PCB layout?

The exposed pad of the HMC939ATCPZ-EP-R7 must be soldered to a solid PCB ground plane to ensure both thermal dissipation and RF return path integrity. Per datasheet Figure 3 and Pin Function Descriptions, failure to connect EPAD to ground degrades insertion loss, return loss, and thermal performance - especially critical above 20 GHz.

What logic voltage levels are compatible with the P0–P4 control inputs of the HMC939ATCPZ-EP-R7?

The P0–P4 inputs of the HMC939ATCPZ-EP-R7 accept CMOS- and TTL-compatible logic: VINL ≤ 0.8 V (low), VINH ≥ 2 V (high), with input current <1 µA. No internal pull-up or pull-down resistors exist, so all five lines must be actively driven to valid logic states - floating pins will cause undefined attenuation behavior.

Is the HMC939ATCPZ-EP-R7 pin-compatible with the commercial-grade HMC939ALP4E?

Yes, the HMC939ATCPZ-EP-R7 and HMC939ALP4E share identical pin configuration, function mapping, and 24-lead footprint - though the former uses an LFCSP package with exposed pad grounding requirement while the latter uses QFN. Electrical interface and control timing are fully compatible, enabling drop-in replacement where military specs are not required.