Analog Devices Inc. HMC871LC5TR-R5

Overview

HMC871LC5TR-R5 from Analog Devices (formerly Hittite Microwave) is a GaAs MMIC distributed driver amplifier optimized for optical modulator biasing and high-speed data transmission. It delivers 15 dB gain from DC to 20 GHz, adjustable 4 V_p-p output swing, ±0.5 dB gain flatness, and <300 fs additive RMS jitter at 10–22.5 Gbps-enabling precise drive of EA-type optical modulators in 10G/40G coherent transmitters.

For engineers reviewing the HMC871LC5TR-R5 datasheet, HMC871LC5TR-R5 pinout, HMC871LC5TR-R5 application, or HMC871LC5TR-R5 equivalent, key selection criteria include its 5–8 V supply flexibility, internal 50 Ω I/O matching, cross-point adjustability, low power dissipation (<0.25 W at 2.5 V_p-p), and operation across –40 °C to +85 °C industrial temperature range.

Technical Context

The HMC871LC5TR-R5 employs a GaAs PHEMT distributed amplifier architecture with on-chip bias control and RF-coupled I/Os. Its gain block supports DC-coupled input/output with external DC blocking, while VC and Vgg pins enable independent adjustment of output amplitude and eye-crossing point.

It operates as a pre-driver stage in multi-gigabit optical transmitters, delivering scalable output power (up to 18 dBm Psat) and maintaining group delay variation ≤±15 ps from 1–12 GHz-critical for preserving signal integrity in NRZ and PAM-4 modulation schemes used in SONET OC-192, 10GbE, and 40G DQPSK systems.

Key Specifications

Pinout & Package

The HMC871LC5TR-R5 is housed in a leadless 5×5 mm ceramic surface-mount package (alumina body, gold-over-nickel plating, MSL3 rating) with an exposed ground paddle requiring soldering to PCB RF ground.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar optical modulator driver applications.

Compared with HMC988LP5E and LMH6401IRHA, the HMC871LC5TR-R5 uniquely balances wideband GaAs performance, analog configurability (VC/Vgg), and industrial temperature support-making it the preferred choice for field-deployed 10G/40G optical transmitters requiring robust, tunable drive capability.

Availability

HMC871LC5TR-R5 is available at Aetrix Electronics and suitable for SONET OC-192 transmission systems, 10GbE optical modules, and 40G DQPSK pre-driver applications requiring stable component supply across extended temperature and high-reliability optical infrastructure deployments.

Supply support for HMC871LC5TR-R5 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/microwave product portfolio, including GaAs MMICs for defense, communications, and test equipment.

The HMC871LC5TR-R5 belongs to Hittite's optical modulator driver family, designed specifically to address the voltage swing, jitter, and bandwidth requirements of electro-absorption and Mach-Zehnder modulators in telecom and datacom transmitters.

FAQ

What is the recommended power-up sequence for the HMC871LC5TR-R5?

Apply ground first, then set Vgg to –2 V (to disable drain current), followed by VC = +0.5 V and Vdd = +5 V or +8 V. Next, adjust Vgg to achieve target Idd (50 mA at 5 V or 75 mA at 8 V), and finally apply the RF input signal. This sequence prevents gate overvoltage and ensures stable bias establishment before RF activation. The HMC871LC5TR-R5 must be handled as ESD-sensitive (Class 1A) throughout this process.

Does the HMC871LC5TR-R5 support DC-coupled input and output interfaces?

Yes, the HMC871LC5TR-R5 features DC-coupled RFIN and RFOUT pins, each internally matched to 50 Ω. However, external AC coupling capacitors are required on both ports to isolate DC bias conditions between the driver and adjacent circuitry (e.g., laser diode drivers or modulator electrodes). The HMC871LC5TR-R5 datasheet specifies 0.5 V_p-p AC-coupled input for nominal 4 V_p-p output.

How does the VC pin affect output swing and modulator compatibility?

The VC pin adjusts the HMC871LC5TR-R5's output voltage swing from 0 to 4 V_p-p by controlling internal current sources. At VC = +0.5 V, the device delivers nominal 4 V_p-p swing-ideal for EA modulators with V_π ≈ 3–4 V. Lower VC settings reduce swing linearly, allowing precise matching to modulator V_π and optimizing extinction ratio without external attenuators. This makes the HMC871LC5TR-R5 adaptable across multiple modulator families.

Can the HMC871LC5TR-R5 operate reliably at –40 °C and +85 °C?

Yes, the HMC871LC5TR-R5 is fully specified and qualified for continuous operation from –40 °C to +85 °C. Electrical parameters-including gain flatness (±0.5 dB), additive jitter (<300 fs), and Psat (18 dBm @ 1–12 GHz)-are guaranteed across this range at Vdd = 8 V. Its GaAs MMIC process and ceramic package ensure stable RF performance in outdoor telecom cabinets and industrial optical line terminals where ambient extremes occur.

What is the thermal resistance and heatsinking requirement for the HMC871LC5TR-R5?

The HMC871LC5TR-R5 has a channel-to-ground-paddle thermal resistance of 66.31 °C/W. With maximum power dissipation of 0.6 W at Vdd = 8 V, junction temperature rise above ambient is ~40 °C-well within the 175 °C absolute max. To maintain reliability, the exposed ground paddle must be soldered to a solid copper ground plane with ≥6 thermal vias (0.3 mm diameter) connecting to inner/secondary ground layers. The HMC871LC5TR-R5 evaluation board (PCB #127381) includes this thermal design.