Analog Devices Inc. LTC2171IUKG-14#PBF

Overview

LTC2171IUKG-14#PBF from Analog Devices (formerly Linear Technology) is a 14-bit, 4-channel simultaneous-sampling analog-to-digital converter optimized for high-dynamic-range communications signal digitization. It delivers 73.5dB SNR and 90dB SFDR at 40Msps sampling rate, with ultralow 0.15psRMS jitter enabling clean undersampling of IF frequencies up to 140MHz in software-defined radio and cellular base station front-ends.

For engineers reviewing the LTC2171IUKG-14#PBF datasheet, LTC2171IUKG-14#PBF pinout, LTC2171IUKG-14#PBF application, or LTC2171IUKG-14#PBF equivalent, key selection considerations include its quad-channel synchronization capability, serial LVDS output architecture (1- or 2-lane), 1.8V single-supply operation, and industrial temperature range (–40°C to +85°C) for rugged embedded data acquisition systems.

Technical Context

The LTC2171IUKG-14#PBF implements four independent 14-bit ADC cores with shared sample-and-hold and internal clock duty cycle stabilizer, supporting differential or single-ended encode inputs (PECL/LVDS/TTL/CMOS). Its 800MHz full-power bandwidth and ±1LSB INL ensure fidelity across wideband RF input signals.

Digital interface uses configurable serial LVDS outputs per channel-either one bit per lane (1-lane mode) or two bits per lane (2-lane mode)-with optional on-chip 100Ω termination and adjustable 1.75mA/3.5mA output current. Configuration is managed via SPI port or parallel logic pins (PAR/SER mode).

Key Specifications

Pinout & Package

52-pin (7mm × 8mm) plastic QFN package with exposed thermal pad (Pin 53 = GND). Requires soldering exposed pad to PCB ground plane for thermal and electrical integrity.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar quad-channel, 14-bit ADC applications.

Compared with AD9257BSTZ-40, LTC2171IUKG-14#PBF offers superior jitter and SFDR for RF-intensive applications, while LTC2170IUKG-14#PBF provides identical functionality at reduced speed and power-enabling scalable design reuse across product tiers.

Availability

LTC2171IUKG-14#PBF is available at Aetrix Electronics and suitable for cellular infrastructure, software-defined radio development, and portable medical imaging systems requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for LTC2171IUKG-14#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 communications, industrial, automotive, and healthcare markets.

The LTC217x family was designed specifically for high-dynamic-range, multichannel digitization in RF and instrumentation applications-emphasizing low jitter, simultaneous sampling accuracy, and flexible LVDS serialization to simplify high-speed digital interfacing.

FAQ

What is the maximum sampling rate supported by the LTC2171IUKG-14#PBF?

The LTC2171IUKG-14#PBF is rated for a maximum sampling rate of 40Msps, as confirmed in the "Timing Characteristics" table of its datasheet. This speed grade distinguishes it from the LTC2172-14 (65Msps) and LTC2170-14 (25Msps) variants within the same pin-compatible family. Operation above 40Msps is not guaranteed and may degrade AC performance metrics such as SNR and SFDR.

Does the LTC2171IUKG-14#PBF support internal voltage reference operation?

Yes, the LTC2171IUKG-14#PBF supports internal reference operation. When the SENSE pin is tied to VDD, the device selects the internal 1.25V reference and configures the analog input range to ±1V differential. The internal reference exhibits ±25ppm/°C drift and 1.225V to 1.275V output tolerance at 25°C, enabling self-contained operation without external reference components.

How many LVDS data lanes does the LTC2171IUKG-14#PBF use per channel?

The LTC2171IUKG-14#PBF supports both 1-lane and 2-lane LVDS serialization per channel, selected via the CS pin in parallel programming mode (PAR/SER = VDD). In 2-lane mode, each channel outputs two bits simultaneously (e.g., OUT1A+/– and OUT1B+/–), halving the required data rate versus 1-lane mode where only one bit is output per clock edge.

What is the purpose of the VCM12 and VCM34 pins on the LTC2171IUKG-14#PBF?

VCM12 and VCM34 are dedicated common-mode bias outputs that each source a nominally VDD/2 voltage (1.8V supply → ~0.9V) to set the common-mode level of their respective analog input pairs. VCM12 biases AIN1+/– and AIN2+/–; VCM34 biases AIN3+/– and AIN4+/–. Each must be bypassed to ground with a 0.1µF ceramic capacitor to maintain low-noise, stable common-mode voltage for optimal ADC linearity.

Can the LTC2171IUKG-14#PBF operate with a single 1.8V supply?

Yes, the LTC2171IUKG-14#PBF operates from a single 1.8V analog supply (VDD) and a separate 1.8V digital output supply (OVDD), both specified over 1.7V to 1.9V. This dual-rail 1.8V architecture isolates analog and digital noise domains while eliminating the need for additional voltage regulators or level shifters in compact, low-power designs.