Analog Devices Inc. LTC2344IUH-18#PBF

Overview

LTC2344IUH-18#PBF from Analog Devices (acquired Linear Technology) is an 18-bit, quad-channel simultaneous-sampling SAR ADC with differential SoftSpan inputs, ±4LSB INL, 95dB SNR, and 400ksps per channel throughput. It operates from a 5V supply with integrated 4.096V reference and buffer, supports CMOS/LVDS serial interfaces, and is rated for –40°C to +85°C operation in industrial process control and high-speed data acquisition systems.

For engineers reviewing the LTC2344IUH-18#PBF datasheet, LTC2344IUH-18#PBF pinout, LTC2344IUH-18#PBF application, or LTC2344IUH-18#PBF equivalent, key selection criteria include per-channel SoftSpan range configurability (±4.096V/0–4.096V/±2.048V/0–2.048V), 102dB CMRR, rail-to-rail input overdrive tolerance, and 32-lead 5mm × 5mm QFN package with exposed thermal pad.

Technical Context

The LTC2344IUH-18#PBF implements a successive approximation register architecture with internal conversion clock and zero-cycle latency. Its analog front-end features fully differential inputs with 0V to VDD common mode range and 102dB CMRR at 200Hz, enabling direct digitization of bipolar, unipolar, and arbitrary common-mode signals without external level-shifting circuitry.

Digital interface flexibility includes pin-selectable SPI CMOS (1.8V–5V) or LVDS modes, supporting 1–4 data lanes in CMOS mode to optimize bus width versus throughput. Per-channel SoftSpan configuration is set via SPI command on a conversion-by-conversion basis, allowing dynamic range adaptation across all four channels independently.

Key Specifications

Pinout & Package

Package: 32-lead (5mm × 5mm) plastic QFN (UH) with exposed thermal pad (Pin 33) soldered 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-resolution simultaneous-sampling ADC applications.

Compared with AD7606C-18 and ADS8684, the LTC2344IUH-18#PBF uniquely combines per-channel SoftSpan configurability, true simultaneous sampling, LVDS/CMOS interface selectability, and 102dB CMRR in a compact 5mm × 5mm QFN - making it optimal for space-constrained, noise-immune, multi-range industrial DAQ systems where channel synchronization and input flexibility are critical.

Availability

LTC2344IUH-18#PBF is available at Aetrix Electronics and suitable for programmable logic controllers, industrial process control systems, and high-speed data acquisition requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for LTC2344IUH-18#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 LTC2344-18 product line was developed by Linear Technology (acquired by ADI in 2017) to address demanding industrial and instrumentation applications requiring simultaneous multi-channel sampling, flexible input ranges, and robust noise immunity in compact packages.

FAQ

What is the maximum sampling rate per channel for the LTC2344IUH-18#PBF?

The LTC2344IUH-18#PBF achieves 400ksps per channel when all four channels are enabled. Throughput increases to 500ksps, 666ksps, and 1000ksps when three, two, or one channel is active respectively - enabling adaptive bandwidth allocation in resource-constrained systems while maintaining 18-bit resolution and no missing codes across all configurations.

Does the LTC2344IUH-18#PBF require an external reference voltage?

No, the LTC2344IUH-18#PBF includes an integrated 2.048V bandgap reference and a buffered 4.096V output (REFBUF) usable directly. However, REFIN can be overdriven with a 1.25V–2.2V external reference for improved initial accuracy and temperature stability, or REFBUF can be overdriven with a 2.5V–5V source when the internal buffer is disabled by grounding REFIN.

How does the SoftSpan feature work on the LTC2344IUH-18#PBF?

The SoftSpan feature on the LTC2344IUH-18#PBF allows each of the four channels to be independently configured on a per-conversion basis for ±4.096V, 0–4.096V, ±2.048V, or 0–2.048V input ranges via SPI commands. This eliminates external gain-switching hardware and enables dynamic range optimization - for example, measuring both high-voltage motor phase currents and low-level thermocouple outputs on the same device without signal conditioning changes.

What is the significance of the 102dB CMRR specification for the LTC2344IUH-18#PBF?

The 102dB CMRR at 200Hz means the LTC2344IUH-18#PBF rejects common-mode interference - such as 50/60Hz mains pickup or ground-loop noise - 10× more effectively than a typical 80dB CMRR ADC. This allows direct connection to sensors in electrically noisy industrial environments without additional filtering or isolation, preserving signal fidelity and reducing system cost and complexity.

Can the LTC2344IUH-18#PBF operate in LVDS mode and CMOS mode simultaneously?

No, the LTC2344IUH-18#PBF supports only one digital interface mode at a time, selected by the LVDS/CMOS pin (Pin 14): tied to OVDD for LVDS, or to GND for CMOS. Both modes use SPI-compatible timing but differ in voltage levels, termination, and noise immunity - LVDS provides superior EMI rejection for long traces or noisy environments, while CMOS offers simpler interfacing with standard microcontrollers.