Analog Devices Inc. 112697-HMC448LC3B

Overview

HMC448LC3B from Analog Devices (formerly Hittite Microwave) is a GaAs MMIC x2 active frequency multiplier in a RoHS-compliant 3×3 mm SMT package, delivering +11 dBm typical output power from 22–25 GHz when driven by 0 dBm input, with >20 dBc Fo/3Fo isolation up to 22 GHz and -135 dBc/Hz SSB phase noise at 100 kHz offset - used in 40 Gbps clock generation and LO multiplier chains for point-to-point radios.

For engineers reviewing the HMC448LC3B datasheet, HMC448LC3B pinout, HMC448LC3B application, or HMC448LC3B equivalent, key selection criteria include its 20–25 GHz output bandwidth, single +5 V supply operation at 48 mA, 50 Ω AC-coupled RF ports, and compatibility with surface-mount manufacturing without wire bonding.

Technical Context

The HMC448LC3B operates as a broadband ×2 harmonic generator using GaAs PHEMT technology, accepting 10–12.5 GHz input to produce 20–25 GHz output. It requires no external biasing beyond +5 V and integrates internal matching for 50 Ω RFIN and RFOUT interfaces across full band.

Its architecture delivers high fundamental and third-harmonic suppression (>20 dBc), low additive phase noise (-135 dBc/Hz @ 100 kHz), and stable performance over -40°C to +85°C - enabling use in high-data-rate timing and microwave LO synthesis where spectral purity and thermal robustness are critical.

Key Specifications

Pinout & Package

Package: 3×3 mm ceramic QFN (alumina body, gold-over-nickel plating, MSL3, exposed ground paddle). All ground pins and paddle must be soldered to PCB RF ground per layout guidelines.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar active frequency multiplier applications.

Compared with HMC448LC3B, HMC575LC3B extends upper frequency range but shifts input requirements, while QM11036 trades phase noise for output power and thermal robustness - making HMC448LC3B optimal for precision clocking and low-jitter LO synthesis where spectral purity dominates.

Availability

HMC448LC3B is available at Aetrix Electronics and suitable for SONET OC-192 clock generation, point-to-point radio LO synthesis, and millimeter-wave test instrumentation requiring stable component supply, consistent parametric performance, and long-term production support.

Supply support for HMC448LC3B 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 GaAs and GaN MMICs for defense, communications, and instrumentation markets.

The HMC448LC3B belongs to Hittite's legacy active multiplier family designed specifically for broadband, low-phase-noise frequency translation in 40 Gbps optical and E-band wireless infrastructure.

FAQ

What is the recommended input drive level for optimal performance of the HMC448LC3B?

The HMC448LC3B achieves best output power and harmonic suppression at 0 dBm input drive, delivering +11 dBm typical output from 22–25 GHz. It tolerates -4 to +6 dBm input, but drive levels above +4 dBm increase risk of compression and degraded Fo/3Fo isolation. For HMC448LC3B, maintaining ±1 dB drive stability ensures consistent phase noise and output power across temperature.

Does the HMC448LC3B require external matching components on RFIN or RFOUT?

No - the HMC448LC3B integrates internal 50 Ω matching on both RFIN (10–12.5 GHz) and RFOUT (20–25 GHz) ports. Only DC blocking capacitors and proper grounding of all GND pins and the exposed paddle are required. External matching networks are unnecessary and may degrade performance; the HMC448LC3B is optimized for direct 50 Ω interface.

What is the thermal resistance and maximum channel temperature specification for the HMC448LC3B?

The HMC448LC3B has a channel-to-ground-paddle thermal resistance of 121 °C/W and a maximum channel temperature rating of 175 °C. Its continuous power dissipation is 744 mW at 85 °C ambient, derating 8.3 mW/°C above that. Proper thermal via placement under the exposed paddle is essential to maintain HMC448LC3B reliability in sustained +85 °C operation.

Can the HMC448LC3B operate from a supply voltage other than +5 V?

Yes - the HMC448LC3B operates across +4.5 V to +5.5 V, with supply current varying from 47 mA to 49 mA. Output power changes by ≤0.5 dB across this range, and phase noise remains stable. However, +5 V is the specified condition for all published specs including +11 dBm output and -135 dBc/Hz phase noise; HMC448LC3B performance is guaranteed only within the absolute max rating of +6.0 Vdc.

Is the HMC448LC3B pin-compatible with other Hittite ×2 multipliers like the HMC447LC3B?

No - the HMC448LC3B is not pin-compatible with HMC447LC3B. While both use the same 3×3 mm package outline, HMC447LC3B has different pin assignments (e.g., RFIN on Pin 3, RFOUT on Pin 10) and operates at 12–16 GHz input / 24–32 GHz output. Substituting HMC448LC3B for HMC447LC3B requires PCB redesign; HMC448LC3B pinout is fixed per its datasheet: RFIN = Pin 5, RFOUT = Pin 11.