Analog Devices Inc. LTC1098CS8#TRPBF

Overview

LTC1098CS8#TRPBF from Analog Devices (formerly Linear Technology) is an 8-bit micropower successive-approximation analog-to-digital converter with integrated sample-and-hold and software-selectable 2-channel multiplexer. It operates from 3V to 6V supply, draws only 88μA typical active current at 500kHz clock, achieves 33kHz maximum sampling rate, and powers down to 1nA. It targets battery-powered sensor interfaces requiring low-power serial ADC functionality in compact SOIC-8 packaging.

For engineers reviewing the LTC1098CS8#TRPBF datasheet, LTC1098CS8#TRPBF pinout, LTC1098CS8#TRPBF application, or LTC1098CS8#TRPBF equivalent, key selection criteria include its 2-channel MUX capability, 3-wire serial interface compatibility, ±0.5LSB total unadjusted error over temperature, shutdown wake-up timing constraints, and SOIC-8 thermal performance (θ_JA = 175°C/W).

Technical Context

The LTC1098CS8#TRPBF implements a switched-capacitor SAR architecture with on-chip sample-and-hold, enabling direct connection to high-impedance sensors without external amplification. Its serial interface uses synchronous half-duplex communication: DIN accepts channel select bits before DOUT returns conversion results on falling CLK edges.

Power management is controlled via CS/SHDN pin - logic high forces 1nA shutdown mode with automatic wake-up requiring ≥10μs delay before first CLK↓ after CS↓; operation at f_CLK ≤ 100kHz inherently satisfies this timing. The VCC/VREF pin serves dual function: power supply input and reference voltage source, limiting full-scale range to VCC when used ratiometrically.

Key Specifications

Pinout & Package

Package: 8-lead plastic SOIC (S8), 175°C/W junction-to-ambient thermal resistance, RoHS-compliant lead-free finish.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADS7822U and MCP3002-I/P, the LTC1098CS8#TRPBF provides unique integration of 2-channel MUX, ultra-low 88μA active current, and true 1nA shutdown-making it optimal for space- and energy-constrained dual-sensor systems where 8-bit resolution suffices.

Availability

LTC1098CS8#TRPBF is available at Aetrix Electronics and suitable for battery-operated systems, remote data acquisition nodes, and isolated data acquisition circuits requiring stable component supply across industrial temperature ranges (0°C to 70°C).

Supply support for LTC1098CS8#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 semiconductors, formed through the acquisition of Linear Technology in 2017.

The LTC1098CS8#TRPBF belongs to ADI's legacy micropower precision ADC product line, designed specifically for energy-sensitive applications including portable instrumentation, sensor networks, and battery management systems where minimal quiescent current and small footprint are critical.

FAQ

What is the maximum clock frequency supported by the LTC1098CS8#TRPBF?

The LTC1098CS8#TRPBF supports a maximum clock frequency of 500kHz at 5V operation, enabling a 33kHz maximum sampling rate. At lower supply voltages (e.g., 3V), the maximum clock frequency reduces to 250kHz per the recommended operating conditions table. Exceeding these limits may cause timing violations in the serial interface or increased conversion error beyond ±0.5LSB specification.

How does the LTC1098CS8#TRPBF handle channel selection during conversion?

The LTC1098CS8#TRPBF uses the DIN pin to accept a 1-bit address before conversion begins: DIN = 0 selects CH0, DIN = 1 selects CH1. This occurs during the initial serial frame prior to DOUT returning the 8-bit result. The channel remains latched until the next CS/SHDN assertion, allowing deterministic sequencing in firmware without additional control lines.

Can the LTC1098CS8#TRPBF operate with an external reference voltage?

No - the LTC1098CS8#TRPBF does not have a dedicated VREF pin. Its reference is internally tied to the VCC/VREF pin, meaning full-scale range equals the supply voltage. For ratiometric accuracy, the supply must be stable; for absolute accuracy, a precision regulator must feed VCC/VREF. In contrast, the pin-compatible LTC1096 variant includes a separate VREF input.

What is the wake-up time requirement after asserting CS/SHDN low on the LTC1098CS8#TRPBF?

The LTC1098CS8#TRPBF requires a minimum 10μs delay between CS/SHDN falling edge and the falling edge of the first CLK that clocks out the MSB bit. This wake-up time ensures internal biasing stabilizes before conversion starts. At clock frequencies ≤100kHz, this delay is inherently satisfied by the clock period, eliminating need for explicit firmware delay.

Does the LTC1098CS8#TRPBF support differential input measurements?

No - the LTC1098CS8#TRPBF provides two independent single-ended analog inputs (CH0 and CH1), each referenced to GND. It cannot measure the voltage difference between CH0 and CH1. For true differential input capability, the pin-compatible LTC1096 variant should be used, which features dedicated +IN and –IN pins with programmable polarity.