Analog Devices Inc. LTC4310IMS-1#PBF

Overview

LTC4310IMS-1#PBF from Analog Devices (formerly Linear Technology) is a bidirectional I²C isolator IC designed for 100kHz systems, enabling galvanic isolation between two I²C buses with independent grounds. It supports transformer- or capacitor-based isolation up to 1500V, features rise time accelerators (2–6mA), ±5kV HBM ESD protection, and integrated stuck-bus recovery (37ms timeout). It is used in isolated power supply monitoring and hot-swappable server backplanes.

For engineers reviewing the LTC4310IMS-1#PBF datasheet, LTC4310IMS-1#PBF pinout, LTC4310IMS-1#PBF application, or LTC4310IMS-1#PBF equivalent, key selection criteria include 100kHz I²C compliance, MSOP-10 package compatibility, thermal shutdown (150°C), undervoltage lockout (2.1–2.7V), and dual-rail level-shifting capability across isolated domains.

Technical Context

The LTC4310IMS-1#PBF implements event-driven differential pulse transmission over TXP/TXN and reception via RXP/RXN, with noise immunity against >20kV/µs common-mode transients. Its logic detection circuitry distinguishes local bus signals from its own outputs, enabling seamless clock stretching, arbitration, and ACK/NACK propagation across isolation barriers.

It employs dual-stage SDA/SCL edge control: a dV/dt limiter enforces 0.35•VCC rise at ≤1.16 V/µs (VCC = 3V) for skew minimization, followed by a slew-limited 2–6mA rise time accelerator activated above 0.45•VCC. Bus idle detection (≥115µs high) and STOP-bit synchronization enable deterministic READY assertion and Hot Swap™ operation.

Key Specifications

Pinout & Package

10-Lead Plastic MSOP package (3mm × 3mm footprint, 0.5mm pitch), thermally enhanced with exposed pad (optional GND connection). Pin 11 is DFN-only; MSOP has no exposed pad.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADM3260ARUZ and ISO1540DR, the LTC4310IMS-1#PBF uniquely balances transformer-based high-voltage isolation (1500V), deterministic stuck-bus recovery, and compact MSOP-10 packaging - making it optimal for industrial hot-swap and medical isolation where external supply routing and protocol fidelity are critical.

Availability

LTC4310IMS-1#PBF is available at Aetrix Electronics and suitable for industrial PMBus monitoring, telecom line card hot-swap, and medical sensor interface applications requiring stable component supply across extended temperature ranges.

Supply support for LTC4310IMS-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 full product support, documentation, and manufacturing continuity for the LTC portfolio.

The LTC4310 family was designed specifically for robust, protocol-transparent I²C isolation in harsh environments - emphasizing hot-swap resilience, high CM transient immunity, and minimal inter-bus timing skew.

FAQ

What is the maximum isolation voltage supported by the LTC4310IMS-1#PBF?

The LTC4310IMS-1#PBF supports up to 1500V isolation when used with appropriate transformers such as the EPF8119S, as validated in the typical application circuit. This rating applies to reinforced insulation across the barrier formed by external components - the IC itself provides the signal conditioning and protocol handling, not the dielectric barrier.

Does the LTC4310IMS-1#PBF require external pull-up resistors on SDA and SCL lines?

Yes, the LTC4310IMS-1#PBF requires external pull-up resistors on both SDA and SCL lines, sized according to bus capacitance and supply voltage. For 100kHz operation, Figure 2 in the datasheet specifies maximum values (e.g., 7.5kΩ for 3.3V/40pF); exceeding these limits risks violating I²C rise-time specifications despite the built-in accelerators.

How does the stuck-bus recovery feature operate in the LTC4310IMS-1#PBF?

When SDA and SCL remain low for 37ms, the LTC4310IMS-1#PBF disables its drivers and generates up to sixteen SCL clock pulses followed by a STOP bit to attempt bus release. Recovery occurs automatically upon detection of simultaneous STOP/idle on both buses - no host intervention or register writes are needed.

Can the LTC4310IMS-1#PBF be used with capacitor-based isolation instead of transformers?

Yes, the LTC4310IMS-1#PBF supports capacitor-coupled isolation for lower-voltage applications (<500V). Coupling capacitors must be ≥47pF and ≥10× board trace parasitic capacitance (CPAR), with careful layout to maintain noise immunity - unlike transformer coupling, capacitive isolation lacks inherent common-mode rejection.

What is the function of the READY pin on the LTC4310IMS-1#PBF?

The READY pin on the LTC4310IMS-1#PBF is an open-drain output that pulls low only after successful synchronization - i.e., when both local and remote I²C buses have been idle for ≥115µs or a STOP bit has occurred. It indicates the device is actively driving SDA/SCL based on decoded RXP/RXN signals.