Analog Devices Inc. 127517-HMC871LC5

Overview

HMC871LC5 from Analog Devices (formerly Hittite Microwave) is a GaAs MMIC distributed driver amplifier optimized for EA 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 10G/40G optical transmitters in SONET OC-192 and 10GbE systems.

For engineers reviewing the HMC871LC5 datasheet, HMC871LC5 pinout, HMC871LC5 application, or HMC871LC5 equivalent, key selection criteria include its wide 5–8 V supply range, internal 50 Ω I/O matching, cross-point adjustability, low power dissipation (<0.25 W at 2.5 V_p-p), and guaranteed performance across –40°C to +85°C industrial temperature range.

Technical Context

The HMC871LC5 employs a GaAs PHEMT distributed amplifier architecture with on-chip broadband matching, enabling flat gain and low group delay variation (±15 ps from 1–12 GHz) across DC–20 GHz. Its dual-bias control (Vgg for drain current, VC for output amplitude) enables independent optimization of power efficiency and eye opening.

It features fully DC-coupled 50 Ω input (RFIN) and output (RFOUT) ports requiring external AC blocking, plus dedicated low-frequency termination pins (ACG1/ACG2) and exposed paddle grounding for RF stability. The 32-lead 5×5 mm alumina package supports high-frequency thermal and signal integrity via direct ground-plane connection.

Key Specifications

Pinout & Package

Package: 32-lead, 5 mm × 5 mm surface-mount ceramic (alumina) package with exposed ground paddle; MSL3, gold-over-nickel plating; thermal resistance θ_ch-gnd = 66.31 °C/W.

Key Features

Applications

Equivalent & Alternatives

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

Compared with HMC988LP5E and LMH5401RTVT, the HMC871LC5 uniquely balances wide supply flexibility (5–8 V), tunable 4 V_p-p output, and sub-300 fs jitter-making it the only option among the three qualified for industrial-temperature EA modulator driving in legacy and hybrid optical systems.

Availability

HMC871LC5 is available at Aetrix Electronics and suitable for SONET OC-192 transmission systems, 10GbE optical transceivers, and 40G DQPSK pre-driver designs requiring stable component supply, long-lifecycle support, and guaranteed RF performance across temperature.

Supply support for HMC871LC5 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 portfolio, specializing in microwave, millimeter-wave, and optical interface ICs for communications infrastructure.

The HMC871LC5 belongs to Analog Devices' optical modulator driver product line, engineered specifically for high-reliability, low-jitter amplification in telecom and datacom transmitters using electro-absorption (EA) and Mach-Zehnder modulators.

FAQ

What is the recommended power-up sequence for the HMC871LC5?

The HMC871LC5 requires strict power sequencing to prevent latch-up or gate damage: first ground all pins and apply no RF signal; set Vgg to –2 V (zero drain current); set VC to +0.5 V; apply Vdd (5 V or 8 V); then adjust Vgg to achieve target Idd (50 mA or 75 mA); finally apply RF input. This sequence ensures safe turn-on of the GaAs PHEMT core and is documented in the HMC871LC5 application note.

Does the HMC871LC5 support AC-coupled input, and what is the required input swing?

Yes, the HMC871LC5 requires AC-coupled input due to its DC-coupled RFIN pin. For nominal 4 V_p-p output, a 0.5 V_p-p AC-coupled input is specified. Input signals must be centered at 0 V DC and limited to +10 dBm maximum to avoid compression or damage. External series capacitors (e.g., 100 nF) are mandatory to isolate upstream DC bias.

How does the VC pin affect output swing and what voltage range is valid?

The VC pin controls output voltage swing linearly from 0 to 4 V_p-p. Applying +0.5 V yields nominal 4 V_p-p; reducing VC lowers swing proportionally. Valid VC range is 0 to 2 V, referenced to ground. Operation outside this range may cause distortion or instability. VC also influences cross-point indirectly, so co-tuning with Vgg is recommended for optimal eye opening.

Can the HMC871LC5 operate at 22.5 Gbps with sub-300 fs jitter, and under what conditions?

Yes, the HMC871LC5 achieves <300 fs additive RMS jitter at 22.5 Gbps using a 10101… pattern, measured with Vdd = 8 V, VC = 0.5 V, and Idd = 75 mA. This performance is guaranteed per the datasheet's Electrical Specifications table and confirmed in Figure 5 (RMS Jitter vs. Vdd). Jitter remains stable across –40°C to +85°C when proper thermal management is applied.

What is the thermal design requirement for continuous operation of the HMC871LC5?

The HMC871LC5 has θ_ch-gnd = 66.31 °C/W and max channel temperature of 175°C. At 0.6 W dissipation (Vdd = 8 V), junction rise above board ground is ~40°C. To maintain T_ch ≤ 125°C, the PCB ground plane must be thermally coupled to a heatsink or chassis with ≤20°C/W total thermal resistance from paddle to ambient. Via density ≥12 per side and 2 oz copper are recommended.