Analog Devices Inc. LTC2428IG#TRPBF

Overview

LTC2428IG#TRPBF from Analog Devices (formerly Linear Technology) is an 8-channel, 20-bit micropower delta-sigma ADC with no-latency digital filtering, integrated oscillator, ±12.5% extended input range relative to VREF, and 1.2 ppm RMS noise. It operates from 2.7V to 5.5V, draws only 200 µA in conversion mode, and delivers 110 dB min 50/60 Hz notch rejection - ideal for precision industrial sensor interfaces requiring channel multiplexing without settling delay.

For engineers reviewing the LTC2428IG#TRPBF datasheet, LTC2428IG#TRPBF pinout, LTC2428IG#TRPBF application, or LTC2428IG#TRPBF equivalent, key selection criteria include guaranteed no-missing-codes 20-bit resolution, single-cycle filter settling after channel change, live-zero input range accommodation, internal oscillator eliminating external timing components, and SPI/MICROWIRE-compatible 4-wire serial interface.

Technical Context

The LTC2428IG#TRPBF implements a decimating FIR filter synchronized to an on-chip oscillator or user-supplied external clock (1 Hz–800 Hz), enabling programmable notch frequency at f_EOSC/2560. Its auto-calibrating architecture performs full-scale and offset correction every conversion cycle, ensuring long-term stability against temperature, supply drift, and aging.

It integrates an 8-channel analog multiplexer with break-before-make switching (290 ns), 120 dB channel-to-channel isolation, and configurable reference input (0.1 V to V_CC). The extended input range (–0.125×V_REF to 1.125×V_REF) directly accommodates sensor overrange and signal-conditioning offsets without external level-shifting circuitry.

Key Specifications

Pinout & Package

Package: 28-lead plastic SSOP (G package), 5.6 mm × 10.2 mm, 0.635 mm pitch, RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-precision, low-power ADC applications.

Compared with LTC2408CG#PBF and ADS1248IPWR, the LTC2428IG#TRPBF uniquely combines 20-bit no-latency multiplexing, integrated 110 dB line rejection, and 200 µA power consumption - making it optimal for battery-powered, multi-channel industrial sensors where timing determinism and EMI resilience are critical.

Availability

LTC2428IG#TRPBF is available at Aetrix Electronics and suitable for weight scales, gas analyzers, direct temperature measurement, and strain-gage transducer systems requiring stable component supply, long-term calibration integrity, and industrial temperature range support (–40°C to +85°C).

Supply support for LTC2428IG#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, 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 LTC2428IG#TRPBF belongs to ADI's precision delta-sigma ADC product line, designed specifically for low-power, high-accuracy sensor signal acquisition in harsh environments where noise immunity, long-term stability, and minimal external components are essential.

FAQ

What is the operating temperature range for the LTC2428IG#TRPBF?

The LTC2428IG#TRPBF is specified for operation from –40°C to +85°C. This industrial temperature grade is confirmed in the Absolute Maximum Ratings table and applies to all electrical specifications unless otherwise noted. The "I" suffix in the part number explicitly denotes this extended range, distinguishing it from the commercial-grade "C" version (0°C to 70°C). All converter characteristics, including INL, noise, and rejection, are guaranteed across this full range.

Does the LTC2428IG#TRPBF require external timing components for 50/60 Hz rejection?

No, the LTC2428IG#TRPBF does not require external timing components for 50/60 Hz rejection. Its integrated oscillator generates a highly accurate conversion clock, and the FO pin configures the digital filter null - tying FO to VCC selects 50 Hz rejection, while tying FO to GND selects 60 Hz rejection. This eliminates crystals, capacitors, or resistors traditionally needed for line-frequency notch filtering.

How does the LTC2428IG#TRPBF handle channel switching without latency?

The LTC2428IG#TRPBF achieves true no-latency operation by completing digital filter settling in a single conversion cycle. When the analog multiplexer channel is changed, the first resulting conversion output is fully settled and accurate - no dummy conversions or waiting periods are required. This behavior is guaranteed by the delta-sigma architecture and internal timing control, and is explicitly verified in the device's timing diagrams and application notes.

Can the LTC2428IG#TRPBF interface directly with a standard SPI host controller?

Yes, the LTC2428IG#TRPBF supports SPI-compatible operation using its 4-wire interface (CSADC, SCK, SDO, DIN). When configured in internal SCK mode (SCK pin as output), it drives the clock synchronously with data; in external SCK mode (SCK as input), it accepts host-generated clocks up to 2 MHz. No protocol translation or glue logic is needed - standard SPI peripherals can read 24-bit results with proper timing alignment per the datasheet's t_KQMIN and t_KQMAX specs.

What is the purpose of the ZSSET and FSSET pins on the LTC2428IG#TRPBF?

The ZSSET (Pin 5) and FSSET (Pin 3) pins define the zero-scale and full-scale reference points for the LTC2428IG#TRPBF's input range. Their difference (V_REF = FSSET – ZSSET) sets the ADC's effective reference voltage. This two-pin configuration enables live-zero operation - allowing input signals from –12.5% to +112.5% of V_REF - and supports flexible reference topologies such as ratiometric sensor excitation or precision voltage references.