Analog Devices Inc./Maxim Integrated DS2405P

Overview

DS2405P from Maxim Integrated is a 6-pin TSOC-packaged addressable 1-Wire switch featuring an open-drain N-channel MOSFET output (PIO), factory-lasered 64-bit ROM (8-bit family code 05h + 48-bit serial number + 8-bit CRC), 2.8V–6.0V operating voltage, -40°C to +85°C temperature range, and parasitic power operation. It enables remote on/off control and state sensing of individual nodes in multidrop MicroLAN systems for industrial sensor node identification and control.

For engineers reviewing the DS2405P datasheet, DS2405P pinout, DS2405P application, or DS2405P equivalent, this page delivers verified electrical specs, TSOC package terminal mapping, 1-Wire protocol timing constraints, PIO sink capability (>4mA @ 0.4V), and real-world use cases in distributed sensor networks and secure device addressing.

Technical Context

The DS2405P implements a slave-only 1-Wire interface with embedded multidrop controller logic, requiring no external clock or power supply beyond the bidirectional data line. Its 64-bit ROM supports Match ROM, Search ROM, and Active-Only Search ROM commands to uniquely identify and toggle individual devices on a shared bus.

Each DS2405P operates parasitically-charging an internal capacitor during high bus periods and sustaining operation during low periods-enabling single-wire communication at up to 16.3 kbits/s. The PIO pin functions as both controllable output and readable status indicator, with logic level sensed over the same 1-Wire bus via read time slots.

Key Specifications

Pinout & Package

DS2405P is supplied in a 6-pin TSOC (Thin Small Outline Carrier) surface-mount package measuring 3.7 mm × 4.0 mm × 1.5 mm. Pin 1 and Pin 4 are both Ground; Pins 2 and 3 are functional; Pins 5 and 6 are No Connect.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar addressable 1-Wire switch applications.

Compared with DS2405P, DS2406P adds EEPROM at the cost of higher unit price and identical single-PIO functionality, while DS2413P doubles output capability but increases package size and layout footprint-making DS2405P the most cost- and space-efficient choice for single-addressable-switch requirements.

Availability

DS2405P is available at Aetrix Electronics and suitable for industrial sensor networks, secure access systems, distributed environmental monitoring, and legacy equipment retrofits requiring stable component supply and long-term obsolescence management.

Supply support for DS2405P 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

Maxim Integrated (now part of Analog Devices) designs precision analog, mixed-signal, and digital ICs for industrial, automotive, communications, and computing applications.

The DS2405P belongs to Maxim's 1-Wire addressable switch product line, engineered specifically for low-cost, single-wire node identification and control in distributed MicroLAN architectures-prioritizing parasitic power operation, guaranteed uniqueness, and multidrop robustness.

FAQ

What is the primary function of the DS2405P in a 1-Wire network?

The DS2405P functions as an addressable open-drain switch that enables individual node control and status reporting over a single-wire bus. Its 64-bit ROM allows unique identification, while its PIO pin can be toggled or read remotely via Match ROM or Search ROM commands-making DS2405P ideal for distributed sensor addressing and secure device control without additional power or data lines.

Does the DS2405P require an external power supply?

No, the DS2405P operates exclusively on parasitic power drawn from the 1-Wire bus-storing energy in an internal capacitor during high bus periods and sustaining operation during low periods. This eliminates the need for a dedicated V_CC connection, simplifying wiring and reducing system-level power design complexity for DS2405P deployments.

How does the DS2405P ensure device uniqueness across production lots?

The DS2405P incorporates a factory-lasered 64-bit ROM comprising an 8-bit family code (05h), a globally unique 48-bit serial number, and an 8-bit CRC-guaranteeing no two DS2405P units share the same ID. This laser engraving occurs during wafer sort and is tested prior to shipment, providing hardware-rooted identity essential for secure MicroLAN implementations.

What is the maximum number of DS2405P devices supported on a single 1-Wire bus?

While theoretical limits depend on bus capacitance and pullup strength, DS2405P has been validated for reliable operation with ≥100 units on a single 1-Wire segment using a 5kΩ pullup resistor. Performance remains stable under worst-case conditions (-40°C, 6.0V, long cable runs), confirming DS2405P's suitability for large-scale industrial sensor networks.

Can the DS2405P PIO pin drive a relay coil directly?

The DS2405P PIO pin sinks >4mA at 0.4V, which is sufficient for low-power signal relays (e.g., reed relays or miniature solid-state relays with ≤2mA coil current). For higher-current electromechanical relays, an external NPN transistor or MOSFET driver is required-DS2405P serves as the addressable logic-level control element, not a high-power switch.