FSA321: Multimedia and USB2.0 Hi-Speed and Audio Switch with Negative Signal Capability and Built-in Termination on Unselected Audio Paths

The FSA321 is a Double-Pole, Double Throw (DPDT) multiplexer that combines a low-distortion audio and a USB2.0 High-Speed (HS) switch path. This configuration enables audio and USB data to share a common connector port. The architecture is designed to allow audio signals to swing below ground. This means a common USB and headphone jack can be used for personal media players and portable peripheral devices.

Since USB2.0 is an industry standard for shared data path in portable devices, FSA321 can be configured for automatic VBUS detection. The FSA321 includes a power-off feature as well as over-voltage tolerance to minimize current consumption when VSW exceeds VCC.

Typical applications involve switching in portables and consumer applications, such as cell phones, digital cameras, and notebooks with hubs or controllers.

Features

• Audio: 1.8Ω Typical On Resistance
• HS-USB: 5Ω Typical On Resistance
• HS-USB: 5pF Typical On Capacitance
• Audio: 1Ω Typical On Resistance
• USB Path -3db Bandwidth: > 720MHz
• Negative Swing Capable Audio Channel
• Power-off Protection on Common D+/R, D-/L Ports
• Automatic USB Detection (Configurable)
• Power-Off Protection on all I/O Ports
• OVT on all I/O Ports
• Flow-Through Pin Out Eliminates PCB Vias
• Built-In Termination on Unselected Audio Paths to Inhibit Audio Pop

Application Notes