Analog Devices Inc. LTC1098IS8#PBF

Overview

LTC1098IS8#PBF from Analog Devices (formerly Linear Technology) is an 8-bit micropower successive approximation ADC with integrated sample-and-hold and software-selectable dual-channel analog multiplexer. It operates from 3V to 6V supply, draws only 88–230μA during conversion (depending on clock rate), powers down to 1nA typical in shutdown, and achieves ±0.5LSB total unadjusted error over –40°C to +85°C. It targets battery-powered remote sensing in industrial monitoring systems.

For engineers reviewing the LTC1098IS8#PBF datasheet, LTC1098IS8#PBF pinout, LTC1098IS8#PBF application, or LTC1098IS8#PBF equivalent, key selection criteria include its 33kHz max sampling rate, 3-wire serial interface compatibility with 8051-style microcontrollers, low-impedance analog input channel switching, and SO-8 package suitability for space-constrained PCB layouts.

Technical Context

The LTC1098IS8#PBF implements a switched-capacitor SAR architecture with on-chip sample-and-hold and a 2-channel analog MUX controlled via DIN serial input. Its conversion sequence requires 8 clock cycles per sample, with configurable wake-up timing (10μs minimum after CS↓ before MSBF CLK↓) to ensure stable internal biasing before data capture.

Digital interface timing is strictly synchronous: DOUT data is valid on CLK↓ edges, DIN setup/hold times are specified at 400ns/150ns (5V) or 1μs/450ns (3V), and CS must remain low for ≥28μs during data transfer at 500kHz clock. The VCC/VREF pin serves dual function-supply rail and reference-enabling ratiometric operation without external voltage references.

Key Specifications

Pinout & Package

Package: 8-lead plastic SOIC (S8), –40°C to +85°C operating temperature range, θ_JA = 175°C/W.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 8-bit micropower ADC applications.

Compared with ADS7822U and MAX11100ETE+, the LTC1098IS8#PBF uniquely balances ultra-low power (1nA shutdown), dual-channel flexibility, and 5V-tolerant 3-wire serial simplicity-making it optimal for cost-sensitive, battery-operated, dual-signal monitoring where 8-bit resolution suffices.

Availability

LTC1098IS8#PBF is available at Aetrix Electronics and suitable for battery gas gauging, remote temperature monitoring, isolated data acquisition, industrial battery monitoring, and portable medical sensor interfaces requiring stable component supply across long production lifecycles.

Supply support for LTC1098IS8#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, serving industrial, automotive, communications, and healthcare markets.

The LTC1098 series belongs to ADI's legacy micropower precision converter product line, designed specifically for energy-constrained applications demanding reliable, low-cost, dual-input analog digitization without external support components.

FAQ

What is the maximum clock frequency supported by the LTC1098IS8#PBF?

The LTC1098IS8#PBF supports up to 500kHz clock frequency when operating from a 5V supply, and up to 250kHz at 3V. At 500kHz, it achieves its maximum 33kHz sampling rate with 16μs conversion time. Exceeding these frequencies risks violating timing margins and degrading total unadjusted error beyond ±0.5LSB specification.

Does the LTC1098IS8#PBF require an external voltage reference?

No, the LTC1098IS8#PBF does not require an external voltage reference. Its Pin 8 (VCC/VREF) serves as both power supply and reference input, enabling true ratiometric operation. This eliminates external reference components and ensures measurement accuracy tracks supply voltage variations-ideal for battery-powered systems where VCC declines over discharge.

How does the dual-channel multiplexer in the LTC1098IS8#PBF operate?

The LTC1098IS8#PBF uses its DIN pin to accept a 1-bit serial address before each conversion: logic low selects CH0, logic high selects CH1. The MUX is software-controlled and non-overlapping-only one channel connects to the ADC core at a time. Channel selection occurs during the CS low period prior to CLK initiation, ensuring clean signal routing without crosstalk.

What is the wake-up time requirement for the LTC1098IS8#PBF after CS activation?

The LTC1098IS8#PBF requires a minimum 10μs delay between CS↓ and the falling edge of the first CLK that clocks out the MSB (Most Significant Bit). This wake-up interval ensures internal bias circuits stabilize before sampling begins. At clock frequencies ≤100kHz, this timing is inherently satisfied by the CLK period itself, eliminating need for explicit delays in firmware.

Can the LTC1098IS8#PBF operate from a 2.65V supply?

No, the LTC1098IS8#PBF is rated for 3V to 6V supply only. The 2.65V minimum applies exclusively to the LTC1098L variant (e.g., LTC1098LIS8#PBF). Using 2.65V on the LTC1098IS8#PBF violates Absolute Maximum Ratings and may cause conversion failures, increased offset error, or undefined behavior-always verify part marking suffix 'L' for sub-3V operation.