Analog Devices Inc. LTC4310CDD-1#PBF

Overview

LTC4310CDD-1#PBF from Analog Devices (formerly Linear Technology) is a bidirectional, transformer- or capacitor-coupled I²C isolator designed for 100kHz systems with galvanic isolation between two I²C buses. It features ±5kV HBM ESD protection, rise time accelerators delivering up to 6mA pull-up current, stuck bus recovery with 16-clock generation, and operates from 3V to 5.5V supply. It enables hot-swappable I²C communication in isolated power supplies and PoE interfaces.

For engineers reviewing the LTC4310CDD-1#PBF datasheet, LTC4310CDD-1#PBF pinout, LTC4310CDD-1#PBF application, or LTC4310CDD-1#PBF equivalent, this page delivers verified electrical parameters, validated DFN-10 package mapping, confirmed 100kHz I²C timing compliance, thermal shutdown behavior at 150°C, and real-world isolation barrier implementation guidance using Ethernet transformers or capacitors.

Technical Context

The LTC4310CDD-1#PBF implements event-driven differential pulse transmission across an isolation barrier via TXP/TXN outputs and RXP/RXN inputs, supporting up to 1500V isolation. Its dual-stage rise control regulates SDA/SCL edges first at dV/dt = 0.8–1.4 V/µs (0.35•VCC threshold), then activates 2–6mA slew-limited pull-up current above 0.45•VCC.

It embeds autonomous bus management: READY asserts low only after simultaneous STOP/idle detection on both local and remote buses; a 37ms stuck-bus timer triggers SCL clock bursts and STOP-bit recovery; EN input enables <0.1µA shutdown mode; and internal UVLO (2.1–2.7V) with 90–270mV hysteresis ensures clean power-on sequencing.

Key Specifications

Pinout & Package

Package: 10-lead (3mm × 3mm) plastic DFN with exposed pad (pin 11), rated for 0°C to 70°C ambient operation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar I²C isolator applications.

Compared with ADUM1250ARZ and SI8602AC-B-IS, the LTC4310CDD-1#PBF uniquely integrates I²C-aware isolation - including rise time acceleration, READY synchronization, and autonomous 37ms stuck-bus recovery - eliminating need for external components or firmware workarounds in compliant 100kHz systems.

Availability

LTC4310CDD-1#PBF is available at Aetrix Electronics and suitable for isolated I²C sensor interfaces, hot-swappable server backplanes, and Power-over-Ethernet PD interfaces requiring stable component supply across industrial and computing applications.

Supply support for LTC4310CDD-1#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 acquired Linear Technology in 2017 and maintains its precision analog and interface IC portfolio. The company specializes in high-reliability signal conditioning, isolation, and power management solutions for demanding environments.

The LTC4310 product line was designed specifically for robust, protocol-transparent I²C isolation in systems requiring galvanic separation, hot-swap capability, and autonomous bus error recovery - targeting industrial automation, medical equipment, and telecom infrastructure.

FAQ

What is the maximum isolation voltage supported by the LTC4310CDD-1#PBF?

The LTC4310CDD-1#PBF itself does not define isolation voltage; it enables system-level isolation up to 1500V when paired with appropriate barrier components such as the EPF8119S Ethernet transformer or properly rated coupling capacitors. Its internal architecture - including differential TXP/TXN and RXP/RXN interfaces, ±5kV HBM ESD rating, and common-mode transient immunity of 20kV/µs - is engineered to sustain reliable operation under these conditions. Actual isolation rating depends on PCB layout, transformer specification, and creepage/clearance compliance.

Does the LTC4310CDD-1#PBF support standard I²C clock stretching and arbitration?

Yes, the LTC4310CDD-1#PBF fully supports I²C clock stretching, arbitration, and multi-master operation across the isolation barrier. Its logic detection circuitry distinguishes externally driven SDA/SCL transitions from its own outputs, enabling seamless bidirectional communication. Both local and remote buses observe identical timing behavior - including START/STOP generation, ACK/NACK handshaking, and clock synchronization - without protocol modification or latency penalties beyond fixed propagation delay (170–270ns).

How does the READY pin function in the LTC4310CDD-1#PBF?

The READY pin on the LTC4310CDD-1#PBF is an open-drain output that pulls low only when the device has successfully synchronized both local and remote I²C buses - confirmed by detecting simultaneous STOP bits or bus idle states (≥115µs high). It releases high during startup, thermal shutdown, EN-driven shutdown, stuck-bus disconnect, or communication loss (>4.6ms no RX). This signal enables system-level coordination, such as enabling downstream logic only after isolation link is fully established.

Can the LTC4310CDD-1#PBF be used in 400kHz I²C systems?

No - the LTC4310CDD-1#PBF is specifically characterized and guaranteed for 100kHz I²C operation. Its controlled rise rate (0.8–1.4 V/µs) and internal timing parameters (e.g., tPHL = 170–270ns) are optimized for this frequency. For 400kHz systems, the pin-compatible LTC4310CDD-2#PBF must be used, which provides faster rise rate control (2–6.9 V/µs) and validated timing margins at the higher speed. Substituting the -1 version risks setup/hold violations and communication failure.

What happens when the SDA or SCL line remains low for longer than 37ms on the LTC4310CDD-1#PBF?

When SDA or SCL remains low for ≥37ms (typical), the LTC4310CDD-1#PBF triggers its stuck bus recovery sequence: it disables its SDA/SCL drivers, releases READY high, and generates up to sixteen SCL clock pulses to attempt freeing the bus. If SDA releases high before sixteen clocks, it stops immediately; otherwise, it issues a STOP bit on both lines. Recovery occurs automatically once both buses return to idle and a STOP bit is detected simultaneously - no reset or EN toggle required.