Diodes Incorporated PI3CH400ZBEX

Overview

PI3CH400ZBEX from Diodes Incorporated is a 4-bit, low-voltage bus switch with active-low enables, designed for high-bandwidth signal routing in hot-plug-capable systems. It operates at 1.8V/2.5V/3.3V supply voltages, delivers 500 MHz bandwidth, features 4–8 Ω on-resistance, and supports rail-to-rail analog switching (0–5V with 3.3V V_CC). It is used in PCIe Gen1/2 re-timing paths and backplane data switching.

For engineers reviewing the PI3CH400ZBEX datasheet, PI3CH400ZBEX pinout, PI3CH400ZBEX application, or PI3CH400ZBEX equivalent, key selection criteria include enable polarity (active-low), QFN-14 package thermal performance, 500 MHz –3 dB bandwidth, 8 kV HBM ESD rating, and 5 V I/O tolerance during power-off states.

Technical Context

The PI3CH400ZBEX implements four independent bidirectional analog/digital switches controlled by three active-low enable inputs (EN0–EN2), each gating one A–B channel pair. Its MOSFET-based switch architecture eliminates ground bounce and adds negligible propagation delay (<0.3 ns typical).

It supports beyond-rail switching: with 3.3 V V_CC, it passes 0–5 V signals; with 2.5 V V_CC, it handles 0–3.3 V; with 1.8 V V_CC, it supports 0–1.8 V. Input logic is 5 V tolerant regardless of supply voltage, enabling mixed-voltage interface bridging.

Key Specifications

Pinout & Package

The PI3CH400ZBEX is housed in a 14-pin, 3.5 mm × 3.5 mm, 0.5 mm pitch QFN (ZB) package with exposed thermal pad for enhanced power dissipation in compact PCB layouts.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 4-bit bus switch applications.

Compared with SN74CBT3244PWR and TS3A27518EIPWR, the PI3CH400ZBEX uniquely combines 500 MHz bandwidth, active-low enables, beyond-rail analog switching, and 8 kV ESD - making it optimal for hot-plug PCIe, telecom backplanes, and mixed-voltage video routing where signal fidelity and robustness are critical.

Availability

PI3CH400ZBEX is available at Aetrix Electronics and suitable for PCIe Gen1 re-timing, hot-pluggable telecom backplanes, and multi-voltage SoC interface bridging requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant packaging.

Supply support for PI3CH400ZBEX 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 analog, logic, and power management solutions for industrial, computing, and communications markets.

The PI3CH400ZBEX belongs to Diodes' Pericom® high-speed signal integrity product line, engineered specifically for hot-plug-capable, high-bandwidth data routing in telecom infrastructure, server backplanes, and embedded computing platforms.

FAQ

What is the maximum allowable input voltage when V_CC = 0 V?

The PI3CH400ZBEX supports 5 V I/O tolerance even when powered down (V_CC = 0 V), with absolute maximum DC input voltage rated at 6.0 V. This enables safe connection to live backplane traces during hot insertion prior to power sequencing, preventing damage from floating node transients.

Can PI3CH400ZBEX switch analog signals like audio or video?

Yes - its 500 MHz bandwidth, 4–8 Ω on-resistance, and 7 pF on-capacitance support analog video (HDMI, DisplayPort), audio (I²S), and RF control signals. The beyond-rail capability allows 0–5 V analog pass-through using 3.3 V V_CC, eliminating external level shifters in mixed-voltage video routing.

How does the active-low enable affect power-up behavior?

All three enables (EN0–EN2) are active-low and require external pull-up resistors for power-up safety. With V_CC applied but enables un-driven, internal weak pull-downs hold them low - keeping switches disconnected until firmware asserts high logic to enable specific channels, preventing unintended signal coupling.

Is thermal pad soldering required for reliable operation?

Yes - the exposed thermal pad on the ZB QFN package must be soldered to a dedicated PCB thermal plane. Diodes specifies ≥75% solder coverage for optimal thermal resistance (θ_JA ≈ 50°C/W). Omitting pad connection risks junction temperature exceeding 125°C under sustained 120 mA per channel load.