Analog Devices Inc. DC854D-E

Overview

LTC2217 from Analog Devices (formerly Linear Technology) is a 16-bit, 105Msps analog-to-digital converter optimized for high-frequency undersampling applications up to 400MHz full-power bandwidth, with fixed 2.75V_P-P differential input range, 85fs_RMS aperture jitter, and 81.3dBFS noise floor. It serves as the front-end digitizer in wideband receivers requiring high SFDR and low distortion.

For engineers reviewing the LTC2217 datasheet, LTC2217 pinout, LTC2217 application, or LTC2217 equivalent, key selection criteria include its dual-output flexibility (LVDS/CMOS), internal dither and randomizer options, clock duty cycle stabilizer, and compatibility with demanding RF/IF sampling architectures in base stations and spectrum analyzers.

Technical Context

The LTC2217 employs a 16-bit pipelined ADC core with integrated sample-and-hold, correction logic, and programmable output drivers. Its architecture supports both standard and low-power LVDS modes, plus full-rate or demultiplexed CMOS outputs-each configurable via LVDS and MODE pins.

It features a dedicated 1.575V common-mode bias generator (VCM), internal 2.5V reference (selectable via SENSE pin), and optional clock duty cycle stabilizer enabling robust operation across wide input clock duty cycles. Aperture jitter is minimized by ultra-low-noise internal clock path design.

Key Specifications

Pinout & Package

64-pin (9mm × 9mm) plastic QFN package with exposed thermal pad (Pin 65 = GND). Requires soldering of 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 high-speed ADC applications.

Compared with AD9268-105 and LTC2208-14, the LTC2217 delivers superior SFDR and lower jitter while integrating dither, randomizer, and clock stabilization-making it optimal for high-fidelity undersampling where spectral purity is non-negotiable.

Availability

LTC2217 is available at Aetrix Electronics and suitable for cellular infrastructure, test instrumentation, spectrum monitoring, and medical imaging systems requiring stable component supply and long-term production continuity.

Supply support for LTC2217 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 LTC2217 belongs to ADI's high-speed precision ADC product line, engineered specifically for wideband receiver applications demanding exceptional SFDR, low jitter, and flexible digital interfacing in RF and IF signal chains.

FAQ

What is the maximum analog input frequency supported by the LTC2217?

The LTC2217 supports a full-power bandwidth of 400MHz, meaning it can accurately digitize analog input signals up to 400MHz while maintaining specified dynamic performance. This enables direct undersampling of L-band and lower S-band RF signals without requiring analog downconversion stages before the ADC input.

Does the LTC2217 require an external reference voltage?

No-the LTC2217 includes an internal 2.5V bandgap reference. When the SENSE pin is tied to VDD, the device uses this internal reference to establish its 2.75V_P-P full-scale input range. An external 2.5V or 1.25V reference may also be applied to SENSE for identical full-scale range, offering flexibility in system reference architecture.

How does the clock duty cycle stabilizer function in the LTC2217?

The LTC2217's clock duty cycle stabilizer, enabled via the MODE pin, corrects asymmetry in the ENC+ and ENC– clock inputs. It allows high-performance sampling even with duty cycles ranging from 40% to 60%, eliminating the need for external clock conditioning circuits and improving system robustness against clock source variations.

Can the LTC2217 operate in both LVDS and CMOS output modes simultaneously?

No-the LTC2217 supports only one output mode at a time, selected by the voltage applied to the LVDS pin: 0V (full-rate CMOS), 1/3VDD (demultiplexed CMOS), 2/3VDD (low-power LVDS), or VDD (standard LVDS). The digital output structure (bus width, timing, and drive strength) changes accordingly; simultaneous LVDS and CMOS output is not supported.

What is the purpose of the RAND pin on the LTC2217?

The RAND pin enables digital output randomization: when asserted high, it XORs bits D1–D15 with D0 (LSB), reducing deterministic spectral content in the digital output stream. This minimizes radiated EMI from repetitive patterns and eases EMC compliance-especially critical in densely packed RF subsystems where digital noise couples into sensitive analog paths.