Analog Devices Inc. LTC2254IUH#PBF

Overview

LTC2254IUH#PBF from Analog Devices (formerly Linear Technology) is a 14-bit, 105 Msps low-power pipelined analog-to-digital converter optimized for high-frequency signal digitization in demanding communications and imaging systems. It operates from a single 3V supply (2.85V–3.4V), delivers 72.3 dB SNR and 84 dB SFDR at 70 MHz input, supports ±0.5V to ±1V differential input range, and features integrated clock duty cycle stabilizer and flexible reference programming via SENSE pin.

For engineers reviewing the LTC2254IUH#PBF datasheet, LTC2254IUH#PBF pinout, LTC2254IUH#PBF application, or LTC2254IUH#PBF equivalent, key selection criteria include its guaranteed no-missing-codes performance over –40°C to +85°C, 640 MHz full-power bandwidth, low 320 mW power dissipation at 105 Msps, and compatibility with differential RF/IF sampling architectures requiring precise timing control and wide dynamic range.

Technical Context

The LTC2254IUH#PBF implements a six-stage CMOS pipelined ADC architecture with digital correction logic, achieving 5-cycle pipeline latency and deterministic timing behavior. Its sample-and-hold front-end supports differential input drive with 1.5 V common-mode bias (VCM pin), and includes internal reference buffering with programmable gain via SENSE voltage selection.

It integrates a clock duty cycle stabilizer to maintain AC performance across wide input clock duty cycles, and supports multiple output formats (offset binary or 2's complement) selected by MODE pin voltage. The device uses separate analog (VDD) and digital output (OVDD) supplies, enabling interface to 0.5V–3.3V logic families while maintaining analog integrity.

Key Specifications

Pinout & Package

Package: 32-lead (5 mm × 5 mm) plastic QFN with exposed pad (Pin 33 = GND). Requires soldering of exposed pad to PCB ground plane for thermal and electrical performance.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-speed ADC applications.

Compared with AD9246BCPZ-105, LTC2254IUH#PBF offers superior clock jitter immunity and lower power; compared with LTC2264IUP#PBF, it trades 2 bits of resolution for 31% higher throughput-ideal for bandwidth-constrained IF sampling where speed dominates precision.

Availability

LTC2254IUH#PBF is available at Aetrix Electronics and suitable for wireless infrastructure, medical imaging, portable instrumentation, and defense electronics requiring stable component supply across extended temperature ranges.

Supply support for LTC2254IUH#PBF 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, Inc. (ADI) is a global leader in high-performance analog, mixed-signal, and digital signal processing technologies, serving industrial, automotive, communications, and healthcare markets.

The LTC2254IUH#PBF belongs to ADI's high-speed precision ADC product line, designed specifically for RF/IF digitization in communications infrastructure, test equipment, and medical ultrasound systems where dynamic range, low power, and temperature stability are critical.

FAQ

What is the operating temperature range for the LTC2254IUH#PBF?

The LTC2254IUH#PBF is rated for industrial operation from –40°C to +85°C (I-grade), as confirmed by absolute maximum ratings and guaranteed specifications across this range-including INL, DNL, SNR, and SFDR. This makes LTC2254IUH#PBF suitable for deployment in outdoor base stations, avionics, and portable diagnostic devices without derating.

Does the LTC2254IUH#PBF require an external reference voltage?

No-the LTC2254IUH#PBF includes an internal 1.5 V reference with ±30 ppm/°C drift (internal ref) or ±5 ppm/°C (external ref), and supports both internal and external reference configurations. When SENSE is tied to VCM, the internal reference sets ±0.5 V input range; applying an external voltage to SENSE directly scales the full-scale range, eliminating need for external reference ICs in most designs.

How does the clock duty cycle stabilizer in the LTC2254IUH#PBF improve system performance?

The clock duty cycle stabilizer in the LTC2254IUH#PBF actively corrects input clock asymmetry, allowing full AC performance (72.3 dB SNR, 84 dB SFDR) even with 30%–70% duty cycle clocks. This eliminates the need for external duty cycle correction circuits, reduces board area, and improves timing margin in systems using PLLs or dividers with inherent duty cycle distortion.

Can the LTC2254IUH#PBF interface directly with a 1.8V FPGA I/O bank?

Yes-the LTC2254IUH#PBF supports independent OVDD supply from 0.5 V to 3.6 V. Setting OVDD = 1.8 V configures all 14 digital outputs (D0–D13) and OF pin for 1.8 V CMOS levels, enabling direct connection to Xilinx or Intel FPGA banks without level shifters, while maintaining full analog performance on the separate 3 V VDD rail.

What is the significance of the exposed thermal pad (Pin 33) on the LTC2254IUH#PBF QFN package?

The exposed pad (Pin 33) on the LTC2254IUH#PBF is electrically and thermally connected to GND. It must be soldered to a PCB copper pour tied to system ground to achieve specified θ_JA = 34°C/W and ensure reliable operation at 320 mW dissipation. Omitting this connection risks thermal runaway and degraded SNR due to elevated junction temperature.