Analog Devices Inc. LTC2498CUHF#PBF

Overview

LTC2498CUHF#PBF from Analog Devices (formerly Linear Technology) is a 24-bit, 16-channel (8-differential) delta-sigma ADC with Easy Drive input current cancellation, integrated temperature sensor (±2°C absolute accuracy, 1/30°C resolution), and programmable 50Hz/60Hz/simultaneous rejection. It operates from 2.7V to 5.5V, delivers 600nV RMS noise, and supports rail-to-rail inputs with GND-to-VCC common-mode range - ideal for high-precision industrial sensor digitization and temperature-compensated data acquisition.

For engineers reviewing the LTC2498CUHF#PBF datasheet, LTC2498CUHF#PBF pinout, LTC2498CUHF#PBF application, or LTC2498CUHF#PBF equivalent, key selection considerations include its no-latency single-cycle digital filter settling, 2ppm INL, 1ppm offset error, 38-pin 5mm × 7mm QFN package with exposed pad, and support for both internal and external oscillator clocking modes.

Technical Context

The LTC2498CUHF#PBF implements a patented sampling scheme that auto-cancels differential input current, eliminating dynamic errors without on-chip buffering - enabling direct digitization of high-impedance sensors while maintaining DC accuracy. Its 3rd-order delta-sigma modulator feeds a decimating FIR filter with no latency: the first conversion after channel change is valid.

It integrates a precision PTAT temperature sensor (27.8–28.2 mV at 27°C, 93.5 µV/°C coefficient), configurable 50Hz/60Hz rejection via digital filter nulls, and flexible reference handling (0.1V ≤ VREF ≤ VCC, REF+ and REF– independently ranging GND to VCC). The device supports both internal (307.2 kHz) and external oscillator modes, with conversion times of 131–164 ms (1x) or 65.6–82 ms (2x speed).

Key Specifications

Pinout & Package

Package: 38-lead plastic QFN (5mm × 7mm), exposed pad (Pin 39) tied to GND. Requires soldering of exposed pad for thermal and electrical performance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADS1258IRHBT and AD7195BRUZ, the LTC2498CUHF#PBF uniquely combines zero-differential-input-current operation, on-chip temperature sensing, and hardware-configurable dual-line-frequency rejection - making it optimal for low-power, high-accuracy, self-compensating sensor digitization where external buffers and calibration routines must be minimized.

Availability

LTC2498CUHF#PBF is available at Aetrix Electronics and suitable for high-precision industrial process control, portable environmental monitoring, and calibration-grade data acquisition systems requiring stable component supply and long-term manufacturability.

Supply support for LTC2498CUHF#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 semiconductors, acquired Linear Technology in 2017 to expand precision signal chain solutions.

The LTC2498CUHF#PBF belongs to ADI's precision delta-sigma ADC product line, designed specifically for low-power, high-accuracy multichannel sensor digitization in industrial, scientific, and metrology applications where DC stability and noise immunity are critical.

FAQ

What is the operating temperature range for the LTC2498CUHF#PBF?

The LTC2498CUHF#PBF is rated for 0°C to 70°C ambient operation, as indicated by the "C" grade suffix in the part number. This distinguishes it from the I-grade (–40°C to 85°C) and H-grade (–40°C to 125°C) variants. All electrical specifications in the datasheet marked with "l" apply across this full range.

Does the LTC2498CUHF#PBF require external passive components for basic operation?

Yes - the LTC2498CUHF#PBF requires a 10µF tantalum capacitor in parallel with a 0.1µF ceramic capacitor between VCC (Pin 28) and GND, plus 0.1µF capacitors on REF+ and REF– if using external references. No external crystal or oscillator is needed, as the internal 307.2 kHz oscillator suffices for standard operation.

How does the Easy Drive technology in the LTC2498CUHF#PBF eliminate input current errors?

The LTC2498CUHF#PBF uses a patented sampling architecture that automatically cancels differential input current by balancing charge injection across successive sampling phases. This eliminates dynamic errors caused by source impedance mismatch - allowing direct connection of high-impedance sensors (e.g., thermistors, RTDs) without external buffers while preserving DC accuracy.

Can the LTC2498CUHF#PBF measure its own die temperature and external channels simultaneously?

No - the LTC2498CUHF#PBF operates in either external channel measurement mode (CH0–CH15) or internal temperature sensor mode, selected via the SDI command sequence. A single conversion cycle measures one domain only; interleaved sampling requires external sequencing logic or host MCU coordination.

What SPI interface modes does the LTC2498CUHF#PBF support, and how is clock direction determined?

The LTC2498CUHF#PBF supports both internal and external SCK modes. Internal mode (SCK output) is selected when SCK is HIGH at power-up or last CS falling edge; external mode (SCK input) is selected when SCK is LOW. Mode selection is latched and persists until reset or power cycle - no register writes are needed to configure clock direction.