Analog Devices Inc. HMC253LC4

Overview

HMC253LC4 from Analog Devices (formerly Hittite Microwave) is a GaAs MMIC SP8T non-reflective RF switch in a 4×4 mm ceramic SMT package, operating from DC to 3.5 GHz with 1.2 dB typical insertion loss, 35 dB isolation at 2 GHz, and TTL/CMOS-compatible 3-bit control (A/B/C) enabling single +5 V supply operation. It serves as a compact replacement for multi-switch configurations in cellular infrastructure front-ends.

For engineers reviewing the HMC253LC4 datasheet, HMC253LC4 pinout, HMC253LC4 application, or HMC253LC4 equivalent, key selection criteria include its non-reflective topology, integrated 3:8 decoder, DC–3.5 GHz bandwidth, +24 dBm input P1dB, and 40 dBm IIP3 - all critical for WiMAX, 3G basestation, and military RF signal routing.

Technical Context

The HMC253LC4 implements a monolithic GaAs-based SP8T architecture with integrated 3:8 TTL/CMOS decoder, requiring only three digital control lines (CTLA, CTLB, CTLC) and a single +5 V bias (Vdd) to select among eight RF paths (RF1–RF8) from common RFC. Its non-reflective design maintains 50 Ω impedance in both on- and off-states across DC–3.5 GHz.

DC blocking capacitors are mandatory at all RF ports (RFC, RF1–RF8), and the exposed ground paddle must be soldered to PCB RF ground. Operating temperature range is −40 °C to +85 °C, with absolute max Vdd = +7 V and control voltage range of −0.5 V to Vdd +1 V.

Key Specifications

Pinout & Package

Ceramic 4×4 mm surface-mount package (alumina body, gold-over-nickel plating, MSL3), with 24-terminal leadless design and exposed RF ground paddle requiring solder connection to PCB ground plane.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar SP8T RF switch applications.

Compared with HMC547LP3E and QM11036, the HMC253LC4 uniquely combines monolithic SP8T integration, single-supply +5 V operation, and embedded 3:8 decoder - delivering lowest system-level BOM count and fastest time-to-deploy for DC–3.5 GHz infrastructure switching.

Availability

HMC253LC4 is available at Aetrix Electronics and suitable for basestations & repeaters, WiMAX/WiBro fixed wireless, and CATV/DBS headend applications requiring stable component supply, long-lifecycle support, and RoHS-compliant ceramic packaging.

Supply support for HMC253LC4 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, integrating its high-frequency RF IC portfolio into ADI's broader communications and defense solutions.

The HMC253LC4 belongs to Hittite's legacy GaAs MMIC switch product line, engineered specifically for broadband, high-isolation, low-loss RF signal routing in cellular infrastructure, aerospace, and test equipment.

FAQ

What is the recommended DC blocking capacitor value for HMC253LC4 RF ports?

100 pF 0402 capacitors are specified in the HMC253LC4 evaluation board design (PCB #104687) and provide optimal broadband impedance matching from DC to 3.5 GHz. These capacitors must be placed as close as possible to each RF port (RFC, RF1–RF8) to minimize parasitic inductance and preserve return loss performance across the full operating band.

Does HMC253LC4 require external bias sequencing or power-up timing control?

No - the HMC253LC4 has no strict power-up sequencing requirement. Vdd (+5 V) and control signals (CTLA/CTLB/CTLC) may be applied simultaneously. The device draws only 6 mA typical quiescent current and features built-in ESD protection; however, DC blocking capacitors must be installed before applying RF signals to prevent damage from DC offset.

Can HMC253LC4 operate with 0/+5 V control logic instead of 0/+3 V?

Yes - the HMC253LC4 control inputs accept TTL/CMOS logic levels from 0 V (low) to Vdd (+5 V), with guaranteed recognition of logic high at ≥+2.0 V and logic low at ≤+0.8 V. Using +5 V control is fully compliant and does not exceed absolute maximum ratings, though +3 V is preferred for compatibility with mixed-voltage digital systems.

What is the thermal resistance (θ_JA) of HMC253LC4, and how should it be managed in high-power operation?

The HMC253LC4 does not specify θ_JA in its datasheet, but its 150 °C maximum channel temperature and −40 °C to +85 °C operating range require full soldering of the exposed ground paddle to a thermally robust PCB ground plane. For continuous +24 dBm operation, use ≥6 thermal vias under the paddle and a minimum 10 mm² copper pour to maintain junction temperature below 120 °C at ambient +70 °C.

Is HMC253LC4 pin-compatible with any newer Analog Devices SP8T switches?

No - the HMC253LC4 has a unique 24-pin 4×4 mm ceramic layout with specific pin assignments (e.g., Vdd on Pin 8, CTLA on Pin 11). Later ADI SP8T devices like the ADMV1013 use different packages (e.g., 32-lead LGA) and control architectures (SPI interface), making them non-pin-compatible replacements requiring PCB redesign.