Analog Devices Inc. LTC2246IUH#PBF

Overview

LTC2246IUH#PBF from Analog Devices (formerly Linear Technology) is a 14-bit, 25Msps low-power analog-to-digital converter optimized for high-dynamic-range signal digitization in imaging and communications systems. It operates from a single 3V supply (2.7V–3.4V), delivers 74.5dB SNR and 90dB SFDR at 5MHz input, supports ±0.5V to ±1V differential input range, and features clock duty cycle stabilization for robust timing performance.

For engineers reviewing the LTC2246IUH#PBF datasheet, LTC2246IUH#PBF pinout, LTC2246IUH#PBF application, or LTC2246IUH#PBF equivalent, key selection considerations include its 25Msps sample rate, 32-pin QFN package with exposed thermal pad, 575MHz full-power bandwidth, shutdown/nap modes for power management, and compatibility with flexible reference configurations (internal/external).

Technical Context

The LTC2246IUH#PBF implements a six-stage CMOS pipelined ADC architecture with digital correction logic, achieving 5-cycle pipeline latency. Its sample-and-hold circuit features 4pF sampling capacitors and supports both differential and single-ended input drive, with VCM pin providing a precise 1.5V common-mode bias.

It integrates a clock duty cycle stabilizer (enabled via MODE pin voltage), flexible reference programming via SENSE pin (±0.5V to ±1V range), and independent output supply (OVDD = 0.5V–3.6V) enabling direct interfacing with 1.8V/2.5V/3.3V logic. DC accuracy includes ±1LSB INL (typ), ±0.5LSB DNL (typ), and no missing codes over temperature.

Key Specifications

Pinout & Package

Package: 32-lead (5mm × 5mm) plastic QFN with exposed thermal 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-resolution, medium-speed ADC applications.

Compared with ADS8326IPFBT and AD9240ASTZ-25, the LTC2246IUH#PBF uniquely combines 25Msps throughput, on-chip clock stabilization, programmable input range, and 1.5V VCM bias - making it optimal for compact, high-fidelity RF front-ends where timing robustness and analog interface simplicity are critical.

Availability

LTC2246IUH#PBF is available at Aetrix Electronics and suitable for ultrasound imaging systems, portable test instrumentation, spectral analysis equipment, and wired broadband communication receivers requiring stable component supply and guaranteed long-term availability.

Supply support for LTC2246IUH#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 LTC2246IUH#PBF belongs to the LTC224x family of low-power, high-SFDR pipeline ADCs designed specifically for demanding wide-dynamic-range applications including medical ultrasound, communications infrastructure, and portable instrumentation.

FAQ

What is the maximum input frequency supported by the LTC2246IUH#PBF before aliasing occurs?

The LTC2246IUH#PBF has a 25Msps sample rate, so its Nyquist frequency is 12.5MHz. Signals above 12.5MHz will alias into the first Nyquist zone. However, its 575MHz full-power bandwidth allows it to accurately capture wideband inputs up to ~100MHz when used with appropriate anti-alias filtering - the bandwidth specification reflects analog front-end capability, not alias-free digitization limit.

Does the LTC2246IUH#PBF require an external reference voltage?

No, the LTC2246IUH#PBF includes an internal 1.5V reference and VCM output. It can operate with only the internal reference by connecting SENSE to VCM (for ±0.5V input range) or VDD (for ±1V range). External references are optional and supported via REFH/REFL pins for higher precision or custom range requirements.

How does the MODE pin affect output format and clock functionality in the LTC2246IUH#PBF?

The MODE pin on the LTC2246IUH#PBF selects both output coding and clock duty cycle stabilization: GND = offset binary + DCS off; 1/3 VDD = offset binary + DCS on; 2/3 VDD = 2's complement + DCS on; VDD = 2's complement + DCS off. This dual function simplifies system-level configuration without additional control lines.

What is the purpose of the OF (Over/Under Flow) pin on the LTC2246IUH#PBF?

The OF pin on the LTC2246IUH#PBF is an active-high, open-drain output that asserts when the analog input exceeds the selected full-scale range (e.g., >±1V for 2Vpp range), indicating clipping or saturation. It enables real-time signal integrity monitoring and automatic gain control (AGC) loop feedback without requiring software parsing of output data.

Can the LTC2246IUH#PBF interface directly with a 1.8V FPGA I/O bank?

Yes, the LTC2246IUH#PBF supports OVDD from 0.5V to 3.6V. Setting OVDD = 1.8V configures all digital outputs (D0–D13, OF) to be compatible with 1.8V CMOS logic levels, eliminating the need for external level shifters. The OE and SHDN pins also tolerate 1.8V-compatible control signals when driven within their specified VIH/VIL thresholds.