Diodes Incorporated PI7C1401AZFEX

Overview

PI7C1401AZFEX from Diodes Incorporated is a quad-port I²C/SPI expander IC designed for low-speed signal aggregation and module management in optical transceivers and pluggable modules. It supports four independent downstream ports with dedicated SCL/SDA per port, selectable 1 MHz I²C or 33 MHz SPI host interface, programmable LED control (blinking/dimming), and interrupt-driven event reporting. Used in 5G base stations, optical switches, and datacenter storage systems.

For engineers reviewing the PI7C1401AZFEX datasheet, PI7C1401AZFEX pinout, PI7C1401AZFEX application in SFF-8431/SFF-8472 modules, or PI7C1401AZFEX equivalent for multi-port I²C expansion, this page delivers verified electrical specs, validated pin functions, real-world use cases, and cross-compatible alternatives with documented interface and voltage differences.

Technical Context

The PI7C1401AZFEX implements a dual-mode host interface-configurable as either I²C slave (up to 1 MHz) or SPI slave (up to 33 MHz)-with separate 1.8 V–3.3 V host I/O supply. Its downstream side integrates four independent I²C masters, each compliant with SFF-8431, SFF-8472, SFF-8436, SFF-8679, and INF-8074 standards.

It features pre-fetch RAM for critical module data, broadcast mode for simultaneous port writes, and a dedicated interrupt generator triggered by customizable events (e.g., TX_FAULT, RX_LOS, ABS). LED PWM control supports per-port green/yellow status indication with programmable blink timing and dimming levels.

Key Specifications

Pinout & Package

Package: 56-pin TQFN (5 mm × 11 mm, 0.5 mm pitch), lead-free and halogen-free, RoHS 3 compliant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar quad-port I²C/SPI expansion applications.

Compared with MAX7327ATL+T and PCA9557D,118, the PI7C1401AZFEX uniquely integrates four independent I²C masters, SFF-standard compliance, and programmable LED drivers-making it the only solution capable of replacing discrete I²C muxes, GPIO expanders, and LED controllers in optical module management subsystems.

Availability

PI7C1401AZFEX is available at Aetrix Electronics and suitable for 5G base station control, optical switch management, and datacenter storage module applications requiring stable component supply, long-term lifecycle support, and RoHS 3–compliant packaging.

Supply support for PI7C1401AZFEX 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

Diodes Incorporated is a global manufacturer of discrete semiconductors and integrated circuits, specializing in high-performance, energy-efficient solutions for automotive, industrial, and communications markets.

The PI7C1401 product line targets optical interconnect infrastructure, delivering integrated port expansion, DOM aggregation, and LED status management specifically for SFF-compliant pluggable transceivers and modular storage systems.

FAQ

What host interface modes does the PI7C1401AZFEX support, and how are they selected?

The PI7C1401AZFEX supports both I²C slave (up to 1 MHz) and SPI slave (up to 33 MHz) host interfaces. Mode selection is determined by the logic state of the I2C/SPI# pin at power-up: low enables SPI mode, high enables I²C mode. No software reconfiguration is required after boot, and both interfaces share the same register map and interrupt behavior.

Does the PI7C1401AZFEX support hot-plug detection for optical modules?

Yes-it provides native hot-plug detection via dedicated port-level inputs: ABS (Absent), PRSL (Present/Select), and RX_LOS (Receiver Loss of Signal). These signals feed the interrupt generator and can be masked or prioritized per port in the interrupt enable register, enabling reliable plug-in/plug-out event handling without host polling.

Can the PI7C1401AZFEX drive LEDs directly without external current-limiting resistors?

Yes-the LED_GRN[3:0] and LED_YLW[3:0] outputs are current-sink drivers with internal 10 mA current regulation per channel. When configured in PWM mode, they deliver precise brightness control and blinking patterns without external resistors or MOSFETs, meeting typical SFP/QSFP LED drive requirements.

Is the PI7C1401AZFEX compatible with SFF-8472-compliant optical modules?

Yes-its four downstream I²C masters fully comply with SFF-8472's DOM interface specification, including support for all mandatory and optional memory pages, 100 kHz/400 kHz clock rates, and address ranges 0x50–0x51. Each port operates independently with its own SCL/SDA pair, ensuring full electrical and protocol compatibility.