Diodes Incorporated PI4MSD5V9548AZDEX

Overview

PI4MSD5V9548AZDEX from Diodes Incorporated is an 8-channel I²C bus switch with active-low reset, designed to isolate and route I²C signals between one upstream master (SDA/SCL) and eight downstream slave buses (SD0–SD7/SC0–SC7). It supports 1.65 V to 5.5 V operation, features <10 ns reset propagation, ≤9 Ω typical ON-resistance at 4.5–5.5 V, and operates across –40°C to +85°C for industrial sensor hub expansion.

For engineers reviewing the PI4MSD5V9548AZDEX datasheet, PI4MSD5V9548AZDEX pinout, PI4MSD5V9548AZDEX application, or PI4MSD5V9548AZDEX equivalent, key selection criteria include channel-selectable I²C isolation, bidirectional level translation capability, low propagation delay (<0.3 ns), and compatibility with standard/fast-mode I²C timing (up to 400 kHz).

Technical Context

This device implements a digitally controlled analog pass-gate matrix, enabling independent enable/disable of each of eight bidirectional I²C channels via an 8-bit control register accessed over the upstream I²C bus. Channel selection is non-volatile only during power-on; state resets on RESET assertion or power cycle.

It provides voltage-level translation between ports operating at different VCC levels (e.g., 1.8 V master to 3.3 V slaves), with input/output capacitance ≤21 pF per channel and leakage current <±1 µA. The internal power-on reset circuit triggers when VCC drops below 1.3–1.5 V for ≥5 µs.

Key Specifications

Pinout & Package

PI4MSD5V9548AZDEX is packaged in a 24-pin TQFN (ZD) with 0.5 mm pitch and exposed thermal pad. Pin mapping is identical to the TSSOP-24 variant (L package), supporting drop-in layout reuse.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TCA9548APWR and PCA9548ADW, PI4MSD5V9548AZDEX delivers lower ON-resistance, guaranteed reset timing (<4 ns), and full 1.65 V support - making it optimal for low-voltage, high-reliability I²C expansion in space-constrained industrial designs.

Availability

PI4MSD5V9548AZDEX is available at Aetrix Electronics and suitable for industrial sensor hubs, automotive body control modules, and IoT edge gateways requiring stable component supply, long-term lifecycle assurance, and RoHS 3-compliant sourcing.

Supply support for PI4MSD5V9548AZDEX 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, high-reliability components for industrial, automotive, and computing markets.

The PI4MSD5V9548A belongs to Diodes' I²C interface and signal-integrity product line, engineered specifically for scalable, fault-tolerant I²C bus expansion in resource-constrained embedded systems.

FAQ

What is the function of the A0–A2 pins on PI4MSD5V9548AZDEX?

A0, A1, and A2 are hardware address select inputs that configure the device's 7-bit I²C slave address. They allow up to eight PI4MSD5V9548AZDEX units to share the same upstream I²C bus without address conflict. Each combination sets a unique base address from 0x90 to 0x97, enabling daisy-chained or parallel bus expansion topologies.

Does PI4MSD5V9548AZDEX support level translation between different I²C voltage domains?

Yes - PI4MSD5V9548AZDEX supports bidirectional level translation between upstream (SCL/SDA) and downstream (SCx/SDx) ports operating at different voltages within 1.65 V to 5.5 V. This eliminates external level shifters when interfacing 1.8 V microcontrollers with 3.3 V or 5 V sensors, provided VCC is set to the higher domain voltage.

How does the RESET pin affect channel state and I²C communication?

The RESET pin is asynchronous and active-low: asserting it for ≥4 ns forces all eight channel enables to zero, clears the control register, and places all SDx/SCx outputs in high-impedance state. Communication on the upstream bus remains functional after reset, allowing immediate reconfiguration without power cycling or bus arbitration loss.

Can PI4MSD5V9548AZDEX operate reliably at 400 kHz I²C fast mode?

Yes - PI4MSD5V9548AZDEX meets I²C fast-mode timing requirements (0–400 kHz) with ≤0.3 ns propagation delay, ≤21 pF pin capacitance, and compatible rise/fall times. Its 4–9 Ω Ron ensures minimal signal attenuation, and its 400 pF maximum bus load tolerance supports multi-drop configurations without timing violations.