Diodes Incorporated PI3A6386ZLEX

Overview

PI3A6386ZLEX from Diodes Incorporated is a USB Type-C ultra-low-THD audio and data switch array integrating dual SPDT switches for simultaneous USB 2.0 high-speed (480 Mbps) and analog audio routing. It supports USB Type-C Audio Accessory Mode with –110 dB THD+N (20 Hz–20 kHz, 2.0 V_RMS, 32 Ω), 1 Ω audio switch R_ON, and autonomous microphone detection via SBU1/SBU2. Used in notebook and smartphone USB-C ports to route D+/D−, ADR/ADL, MIC+/MIC−, and sideband signals under I²C control.

For engineers reviewing the PI3A6386ZLEX datasheet, PI3A6386ZLEX pinout, PI3A6386ZLEX application, or PI3A6386ZLEX equivalent, key selection criteria include its dual-path switching architecture (USB + audio), negative-signal handling (±3 V), programmable soft-start/stop (5 ms), and integrated microphone orientation detection - all in a 3 mm × 3 mm TQFN-24 package.

Technical Context

The PI3A6386ZLEX implements a functionally partitioned switch matrix: one path handles USB 2.0 differential signaling (1 GHz bandwidth, 5 Ω R_ON) between D+/D− and USB+/USB−; the other routes stereo audio (ADR/ADL) and microphone (MIC+/MIC−) with ±3 V rail-to-rail capability and <1 Ω R_ON. Sideband switches (ISBU1/ISBU2) support plug-orientation-aware SBU1/SBU2 remapping.

Its I²C interface (up to 1 MHz, two selectable slave addresses) controls six independent switch groups: USB/audio mux, mic/sideband mux, sideband crossbar, ground isolation (ADLGND/ADRGND), and soft-start timing via SSCAP capacitor. Microphone detection logic autonomously identifies TRRS/TRS configuration and reports results in the Information Register (Bits b2–b0).

Key Specifications

Pinout & Package

PI3A6386ZLEX is housed in a 3 mm × 3 mm, 24-pin Very Thin Quad Flat No-Lead (TQFN-ZL) package with exposed thermal pad (Pins 9, 21, and thermal pad = GND). Pin functions are validated per Diodes DS40399 Rev 4-2.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar USB-C audio/data switch applications.

Compared with TS3USB30E and MAX14531E, PI3A6386ZLEX uniquely integrates USB 2.0, high-fidelity audio, microphone detection, and sideband remapping in one die - reducing system-level complexity and enabling true USB-C Audio Accessory Mode compliance without auxiliary logic.

Availability

PI3A6386ZLEX is available at Aetrix Electronics and suitable for notebook docking stations, smartphone USB-C audio interfaces, industrial handheld scanners, and tablet peripheral hubs requiring stable component supply and full USB Type-C Audio Accessory Mode compliance.

Supply support for PI3A6386ZLEX 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 analog ICs, specializing in high-performance signal integrity, power management, and interface solutions for consumer, computing, and industrial markets.

The PI3A6386ZLEX belongs to Diodes' USB-C Interface Switch family, designed specifically to consolidate USB 2.0, analog audio, microphone, and sideband signal routing in next-generation USB-C endpoints - addressing the architectural complexity of dual-mode (data/audio) port controllers.

FAQ

What is the maximum allowable voltage on the ADR/ADL pins?

The ADR and ADL pins support a signal range of –3 V to +3 V, enabling true beyond-the-rails operation for DC-coupled audio paths. This specification is validated per DS40399 Rev 4-2 Electrical Characteristics table, ensuring compatibility with legacy analog headsets that output negative-going audio waveforms without AC coupling capacitors.

How does the microphone detection feature operate without external components?

The PI3A6386ZLEX performs autonomous microphone detection by measuring impedance signatures across SBU1/SBU2 using internal comparators and state machines. When triggered via Control Register Bit b3, it identifies TRRS vs. TRS configurations and reports orientation (MIC+/MIC− → SBU1/SBU2 or vice versa) in the Information Register Bits b2–b0 - requiring no external resistors or ADC resources.

Can the PI3A6386ZLEX support USB 2.0 High-Speed (480 Mbps) eye diagram compliance?

Yes - the USB+ and USB− switches deliver 1 GHz –3 dB bandwidth and <5 Ω on-resistance, preserving signal integrity for USB 2.0 High-Speed operation. Per DS40399 Rev 4-2, the data path achieves –25 dB off-isolation at 240 MHz and <30 μs turn-on time, meeting USB-IF eye mask requirements when paired with proper PCB layout and termination.

What is the purpose of the SSCAP pin, and how is timing controlled?

The SSCAP pin sets soft-start and soft-stop timing via an external capacitor (e.g., 0.01 µF yields 5 ms ramp time). This RC network controls the slew rate of audio switch enablement/disabling, eliminating click/pop artifacts caused by DC offset in Class-D or op-amp-based audio amplifiers - a hardware-managed solution requiring no firmware intervention.