Analog Devices Inc./Maxim Integrated DS2482X-100+T

Overview

DS2482X-100+T from Analog Devices is a single-channel I²C-to-1-Wire® bridge IC that acts as a 1-Wire master, supporting both standard (69.3 µs slot) and overdrive (10.5 µs slot) communication speeds, with programmable active/strong pullup and slew-controlled 1-Wire edges for noise reduction in industrial sensor networks.

For engineers reviewing the DS2482X-100+T datasheet, DS2482X-100+T pinout, DS2482X-100+T application, or DS2482X-100+T equivalent, this device enables reliable 1-Wire slave interfacing-especially for parasitically powered EEPROMs and temperature sensors-without host CPU timing intervention, leveraging factory-trimmed internal timers and configurable PCTLZ-driven external MOSFET control.

Technical Context

The DS2482X-100+T implements a self-timed 1-Wire controller with three key configuration-selectable functions: active pullup (APU), strong pullup (SPU), and 1-Wire speed (1WS). Its input/output controller executes time-critical sequences-including reset/presence-detect, write-byte, read-byte, single-bit, and triplet-autonomously after command issuance via I²C.

It features dual-mode I²C interface (100 kHz/400 kHz), two binary address inputs (AD0/AD1) for up to four devices per bus, and a dedicated active-low PCTLZ output to drive an external p-channel MOSFET during strong pullup events, enabling >3 mA 1-Wire power delivery beyond the internal transistor's capability.

Key Specifications

Pinout & Package

DS2482X-100+T is housed in an 8-pin SOIC (150 mil) package with exposed pad for thermal performance and mechanical stability in automated assembly.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar I²C-to-1-Wire bridge applications.

Compared with DS2482S-100+T, the DS2482X-100+T offers superior thermal management and manufacturability in SOIC; compared with TPL100-100I/SO, it delivers essential overdrive timing, PCTLZ control, and stronger pullup-making it the only option for certified medical or industrial 1-Wire deployments.

Availability

DS2482X-100+T is available at Aetrix Electronics and suitable for industrial sensor networks, medical instrumentation, printers, and portable electronics requiring stable component supply, long-term lifecycle assurance, and traceable sourcing.

Supply support for DS2482X-100+T 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. is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving precision instrumentation, industrial automation, and healthcare markets since 1965.

The DS2482X-100+T belongs to Analog Devices' 1-Wire interface product line, engineered specifically to simplify robust, standards-compliant 1-Wire slave integration into I²C-based embedded systems without firmware timing overhead.

FAQ

What is the primary function of the DS2482X-100+T in a system architecture?

The DS2482X-100+T serves as a dedicated I²C-to-1-Wire bridge IC, acting as a fully autonomous 1-Wire master that relieves the host microcontroller from generating time-critical 1-Wire waveforms. It handles reset/presence detection, read/write byte, single-bit, and triplet operations internally, communicating results back via its I²C interface. This enables seamless integration of 1-Wire slaves-including DS18B20, DS2438, and DS2433-into I²C-based designs without modifying host firmware timing logic. The DS2482X-100+T is essential for deterministic, low-error-rate 1-Wire communication in industrial and medical applications.

How does the PCTLZ pin on the DS2482X-100+T enhance 1-Wire power delivery?

The PCTLZ pin on the DS2482X-100+T is an active-low open-drain output that drives the gate of an external p-channel MOSFET during strong pullup events. When the SPU bit in the Configuration Register is set, the DS2482X-100+T asserts PCTLZ low, enabling the external MOSFET to deliver additional current-beyond the internal transistor's 1.5 mA limit-to the 1-Wire bus. This is critical for powering 1-Wire EEPROMs during scratchpad-to-memory copy or SHA-1 computation, and for parasitically powered temperature sensors during conversion. The DS2482X-100+T's ΔVSTRPU spec (≤0.5 V drop at 3 mA) ensures stable voltage under load, and PCTLZ coordination prevents bus contention.

Can the DS2482X-100+T operate with both 3.3 V and 5 V I²C masters?

Yes, the DS2482X-100+T supports dual-supply operation with V_CC ranging from 2.9 V to 5.5 V, making it compatible with both 3.3 V and 5 V I²C masters without level shifters. Its I²C pins (SCL, SDA, AD0, AD1) meet standard I²C voltage thresholds: VIH ≥ 0.7×V_CC and VIL ≤ 0.25×V_CC (for 2.9–3.7 V) or ≤ 0.22×V_CC (for 4.5–5.5 V). Input hysteresis (0.05×V_CC) improves noise immunity, and the device tolerates up to ±20 mA per pin. This flexibility allows the DS2482X-100+T to interface directly with legacy 5 V microcontrollers or modern 3.3 V SoCs-maintaining full 1-Wire timing accuracy and strong pullup performance across both rails.

What 1-Wire timing modes does the DS2482X-100+T support, and how are they selected?

The DS2482X-100+T supports both standard-speed (69.3 µs time slot) and overdrive-speed (10.5 µs time slot) 1-Wire communication, selected via the 1WS bit in its Configuration Register. Standard speed is enabled by default (1WS = 0) and is compatible with all 1-Wire slaves. Overdrive mode (1WS = 1) is activated after issuing an Overdrive-Skip ROM or Overdrive-Match ROM command to downstream slaves, followed immediately by writing the Configuration Register. The DS2482X-100+T's internal oscillator and factory-trimmed timers ensure tight timing tolerance (<±5%) across voltage and temperature. This dual-mode capability allows the DS2482X-100+T to accelerate sensor reads in time-sensitive applications while maintaining backward compatibility.

How does the DS2482X-100+T handle 1-Wire bus shorts or presence detection failures?

The DS2482X-100+T provides real-time fault diagnostics through its Status Register. During each 1-Wire Reset command, it samples the bus at tSI and tMSP: if a logic 0 is detected at tSI, the Short Detected (SD) bit is set; if a presence pulse is observed at tMSP, the Presence-Pulse Detect (PPD) bit is set. Critically, SD and PPD are mutually exclusive-SD = 1 forces PPD = 0. The DS2482X-100+T also reports 1-Wire Busy (1WB) status and Logic Level (LL) for live bus monitoring. These flags enable robust error recovery in applications like industrial sensor arrays, where the host can automatically isolate faulty branches or retry communication-without relying on external comparators or custom firmware logic. The DS2482X-100+T's built-in short detection eliminates need for external protection circuitry in most deployments.