Analog Devices Inc. LTC2449IUHF#TRPBF

Overview

LTC2449IUHF#TRPBF from Analog Devices (formerly Linear Technology) is a 24-bit, 16-channel (8-differential) no-latency delta-sigma ADC with selectable speed/resolution, 200nV_RMS noise at 13.8Hz, simultaneous 50Hz/60Hz rejection, and integrated internal oscillator. It operates from 4.5V to 5.5V supply and supports differential input/reference with GND-to-V_CC common-mode range - used in high-precision weight scales and auto-ranging 6-digit DVMs.

For engineers reviewing the LTC2449IUHF#TRPBF datasheet, LTC2449IUHF#TRPBF pinout, LTC2449IUHF#TRPBF application, or LTC2449IUHF#TRPBF equivalent, key selection criteria include guaranteed modulator stability under all input/reference conditions, 0.0005% INL with no missing codes, autosleep mode enabling 20µA operation at 6.9Hz, and MUXOUT/ADCIN pins for external buffering of multiplexed signals.

Technical Context

The LTC2449IUHF#TRPBF implements a proprietary 3rd-order delta-sigma modulator with decimating FIR filter and continuous per-conversion offset/full-scale calibration. Its no-latency architecture ensures the first conversion after channel/speed/resolution change is fully accurate - eliminating settling delays between multiplexed inputs.

It supports both internal and external clocking via FO and EXT pins, delivers up to 8kHz output rate with external oscillator, and features SoftSpan™ input range handling with bipolar differential input (±0.5·V_REF) independent of reference common-mode voltage.

Key Specifications

Pinout & Package

Package: 38-lead (5mm × 7mm) plastic QFN (UHF), exposed pad (Pin 39) soldered to PCB ground.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-resolution delta-sigma ADC applications.

Compared with ADS1256IPWR, LTC2449IUHF#TRPBF integrates 50/60Hz rejection and internal clocking, reducing external component count; compared with LTC2448IUHF#TRPBF, it adds MUXOUT/ADCIN for external signal conditioning while improving RMS noise by 3dB - critical for ultra-low-level sensor interfaces.

Availability

LTC2449IUHF#TRPBF is available at Aetrix Electronics and suitable for weight scales, auto-ranging DVMs, direct temperature measurement, and high-speed data acquisition requiring stable component supply across industrial temperature range (–40°C to 85°C).

Supply support for LTC2449IUHF#TRPBF 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 acquired Linear Technology in 2017; Linear pioneered high-precision analog ICs including delta-sigma ADCs, voltage references, and power management solutions.

The LTC2449IUHF#TRPBF belongs to the LTC244x family of no-latency delta-sigma ADCs designed for metrology-grade applications demanding guaranteed stability, zero-latency multiplexing, and simultaneous AC-line rejection without firmware overhead.

FAQ

What is the maximum output data rate of the LTC2449IUHF#TRPBF?

The LTC2449IUHF#TRPBF achieves up to 8kHz output rate when using an external 10MHz oscillator on the FO pin and operating in 2X speed mode. With internal oscillator only, the maximum is 7kHz. This high rate maintains 25µV_RMS noise at 3.5kHz, making LTC2449IUHF#TRPBF suitable for multi-channel high-speed acquisition where latency cannot be tolerated.

Does the LTC2449IUHF#TRPBF require external components for basic operation?

No - the LTC2449IUHF#TRPBF includes an internal oscillator and requires only V_CC bypassing (10µF tantalum + 0.1µF ceramic) and optional external reference. Unlike many delta-sigma ADCs, it needs no external crystal, clock buffer, or digital filter; MUXOUT/ADCIN pins are optional for external buffering but not required for standard operation of LTC2449IUHF#TRPBF.

How does the MUXOUT/ADCIN feature improve system performance in the LTC2449IUHF#TRPBF?

MUXOUT/ADCIN separates the multiplexer output from the ADC input, allowing insertion of an external op-amp for gain or filtering without degrading noise or linearity. The LTC2449IUHF#TRPBF's transparent per-conversion calibration automatically removes the buffer's offset and drift - preserving 24-bit accuracy. This eliminates the need for matched external components and simplifies design versus using LTC2448IUHF#TRPBF.

What is the input common-mode voltage range supported by the LTC2449IUHF#TRPBF?

The LTC2449IUHF#TRPBF supports a true differential input with common-mode range from GND – 0.3V to V_CC + 0.3V on all CHx and COM pins. This rail-to-rail capability allows direct interfacing with sensors whose outputs swing near supply rails - such as bridge transducers or thermocouples - without level-shifting circuitry, which would otherwise add noise and error to LTC2449IUHF#TRPBF measurements.

Can the LTC2449IUHF#TRPBF reject 50Hz and 60Hz interference simultaneously?

Yes - the LTC2449IUHF#TRPBF guarantees simultaneous 50Hz and 60Hz line-frequency rejection at its 6.9Hz output rate. This is achieved through inherent delta-sigma modulation and decimation filter design, requiring no external notch filters or digital post-processing. The feature is intrinsic to LTC2449IUHF#TRPBF's architecture and applies across its full operating temperature range (–40°C to 85°C).