Analog Devices Inc. LTC4310CDD-1#TRPBF

Overview

LTC4310CDD-1#TRPBF 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 rise time accelerators (2–6mA), ±5kV HBM ESD protection, stuck bus recovery (37ms timeout), and operates from 3V to 5.5V supply. It enables safe hot-swap insertion into live I²C backplanes in isolated power supply monitoring.

For engineers reviewing the LTC4310CDD-1#TRPBF datasheet, LTC4310CDD-1#TRPBF pinout, LTC4310CDD-1#TRPBF application, or LTC4310CDD-1#TRPBF equivalent, this device serves as a dedicated 100kHz I²C isolator with integrated rise rate control, thermal shutdown, and READY status signaling-critical for industrial SMBus/PMbus interfaces requiring ground separation up to 1500V.

Technical Context

The LTC4310CDD-1#TRPBF implements event-driven differential pulse transmission across an isolation barrier using TXP/TXN outputs and RXP/RXN inputs, with noise rejection for signals below 500mV differential. Its logic detection circuitry distinguishes local bus activity from its own output drive, enabling seamless clock stretching and arbitration pass-through.

Rise rate limiting (0.8–1.4 V/µs at 3V) and slew-limited boost current (2–6mA above 0.45•VCC) ensure I²C rise time compliance under heavy capacitive loads (up to 800pF). Stuck bus recovery initiates after 37ms low state, generating ≤16 SCL clocks and a STOP bit without external intervention.

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 ISO1540DR and ADUM1250ARZ, the LTC4310CDD-1#TRPBF delivers native I²C protocol transparency, built-in rise time acceleration for heavy bus loads, and autonomous stuck bus recovery-making it uniquely suited for drop-in replacement in legacy I²C systems requiring minimal firmware changes and robust field reliability.

Availability

LTC4310CDD-1#TRPBF is available at Aetrix Electronics and suitable for industrial power supply monitoring, isolated SMBus battery management, and Power-over-Ethernet PD interface applications requiring stable component supply and long-term lifecycle support.

Supply support for LTC4310CDD-1#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 acquired Linear Technology in 2017 and maintains its precision analog and interface IC portfolio with rigorous automotive and industrial qualification standards.

The LTC4310 product line was designed specifically for robust, protocol-transparent I²C isolation in harsh environments-targeting applications where ground loop elimination, hot-swap capability, and autonomous fault recovery are critical design requirements.

FAQ

What is the maximum I²C clock frequency supported by the LTC4310CDD-1#TRPBF?

The LTC4310CDD-1#TRPBF is rated for 100kHz maximum SCL clock frequency, matching standard-mode I²C specifications. This is distinct from the LTC4310-2 variant (e.g., LTC4310CDD-2#TRPBF), which supports up to 400kHz. The -1 version ensures reliable timing margin for systems with higher bus capacitance or longer trace lengths.

Does the LTC4310CDD-1#TRPBF require external components for basic operation?

Yes, the LTC4310CDD-1#TRPBF requires external pull-up resistors on SDA and SCL (value dependent on bus capacitance and supply voltage), a ≥0.01µF bypass capacitor on VCC-to-GND, and isolation components-either an Ethernet transformer (e.g., EPF8119S) or coupling capacitors on TXP/TXN/RXP/RXN. READY also needs a pull-up resistor (typically 10kΩ).

How does the stuck bus recovery feature work in the LTC4310CDD-1#TRPBF?

When SDA and SCL remain low for 37ms, the LTC4310CDD-1#TRPBF disables its output drivers, asserts READY high, and transmits a recovery command across the isolation barrier. It then generates up to sixteen SCL clock pulses and issues a STOP bit to reset all connected slaves-fully autonomously, without host MCU involvement.

Can the LTC4310CDD-1#TRPBF be used with different supply voltages on each side of the isolation barrier?

Yes-the LTC4310CDD-1#TRPBF supports independent VCC supplies on each side (e.g., 3.3V on master side, 5V on slave side), enabling level shifting. Its I²C interface logic thresholds scale with local VCC (e.g., VIL = 0.3•VCC), and rise time accelerators activate based on local bus voltage, ensuring interoperability across mixed-voltage domains.

What isolation voltage rating does the LTC4310CDD-1#TRPBF achieve in practice?

The LTC4310CDD-1#TRPBF itself is not rated for a specific isolation voltage; the system-level isolation (e.g., 1500V) depends on the external barrier components. When paired with an appropriately rated Ethernet transformer like the EPF8119S and proper PCB layout (creepage/clearance), end equipment can meet IEC 60950-1 or IEC 62368-1 reinforced isolation requirements.