Analog Devices Inc. 120493-HMC708LP5

Overview

HMC708LP5 from Hittite Microwave Corporation is a digitally controlled variable gain amplifier (DVGA) operating from 1700 MHz to 2200 MHz, delivering −2.5 dB attenuation to +29 dB gain in 0.5 dB steps, with 1 dB noise figure and +37 dBm output IP3, used in LTE/4G base station transmit chains for precise RF power leveling.

For engineers reviewing the HMC708LP5 datasheet, HMC708LP5 pinout, HMC708LP5 application, or HMC708LP5 equivalent, this part supports serial (SPI-compatible), parallel, and latched parallel control modes; features user-selectable power-up state; requires dual supply (3 V and 5 V); and integrates two amplifiers with a 6-bit digital attenuator in a 32-lead 5×5 mm SMT package.

Technical Context

The HMC708LP5 implements a cascaded architecture with AMP1 (input stage), a 6-bit digital attenuator (DAT), and AMP2 (output stage), enabling flexible signal path configuration via Option 1 (AMP1 + DAT) or Option 2 (DAT + AMP2). Gain control resolution is fixed at 0.5 dB LSB across its full 31.5 dB range.

It supports three digital interface modes: serial (SERIN/CLK/LE), direct parallel (D0–D5 active when LE = high), and latched parallel (D0–D5 sampled on LE rising edge). Power-up behavior is determined by PUP1/PUP2 pins or D0–D5 logic states depending on LE level at startup.

Key Specifications

Pinout & Package

32-lead 5×5 mm QFN package with exposed thermal paddle; RoHS-compliant version marked H708; MSL1 rating; Sn/Pb (HMC708LP5) or 100% matte Sn (HMC708LP5E) finish.

Key Features

Applications

Equivalent & Alternatives

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

Compared with HMC708LP5, HMC707LP5 serves distinct frequency bands and cannot substitute in 1700–2200 MHz designs, while QM11030 offers finer resolution and wider bandwidth but sacrifices configurability (no PUP selection, no SEROUT) and dual-supply flexibility critical for mixed-signal transceiver integration.

Availability

HMC708LP5 is available at Aetrix Electronics and suitable for cellular infrastructure, microwave radio, and RF test equipment requiring stable component supply, long-term lifecycle support, and traceable sourcing for production programs.

Supply support for HMC708LP5 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, now part of Analog Devices, specialized in high-performance RFICs and MMICs for wireless infrastructure, defense, and test instrumentation markets.

The HMC708LP5 belongs to Hittite's digital variable gain amplifier product line, designed specifically for precision RF gain control in multi-standard cellular base stations and broadband wireless access equipment.

FAQ

What is the operating frequency range of the HMC708LP5?

The HMC708LP5 operates from 1700 MHz to 2200 MHz, with full electrical specifications guaranteed across this band. Performance metrics including gain flatness, return loss, and IP3 are characterized at 1900 MHz and across the entire range per the datasheet's frequency sweeps. It is not rated for operation below 1700 MHz or above 2200 MHz.

Does the HMC708LP5 support both 3 V and 5 V digital logic levels?

Yes, the HMC708LP5 supports TTL/CMOS-compatible digital inputs: logic low is 0–0.5 V at <1 µA (3 V supply) or 0–0.8 V (5 V supply), and logic high is 2–3 V (3 V) or 2–5 V (5 V). This allows direct interfacing with both 3 V and 5 V microcontrollers or FPGAs without level-shifting circuitry.

How does the power-up state selection work on the HMC708LP5?

The HMC708LP5 provides two power-up configuration methods: if LE is low at power-on, PUP1 and PUP2 pins define one of four preset attenuation states (−31.5 dB to insertion loss); if LE is high, the D0–D5 parallel inputs directly set the initial 6-bit gain code. The device latches the selected state ~200 ms after power stabilization.

Can the HMC708LP5 be used in a receive path application?

Yes, the HMC708LP5 can be deployed in receive paths-particularly in Option 1 configuration (AMP1 → DAT)-where its 1 dB noise figure and high input return loss (>16.5 dB) preserve signal integrity. However, its maximum gain of +27 dB (typ. at 3 V) and −2.5 dB minimum insertion loss make it most effective in mid-chain gain control rather than LNA replacement.

What are the recommended external components for biasing the HMC708LP5?

For +5 V operation, a 270 Ω resistor (Rbias) is recommended on the RES pin to set AMP1 current; for +3 V, a 10 kΩ resistor is used. All Vdd pins require local bypassing: 10 nF (0402) and 1000 pF (0603) capacitors per supply rail, plus a 4.7 µF bulk capacitor on Vdd3. DC blocking capacitors are mandatory on RFIN2 and RFOUT2.