FSA221UMX

Audio Special Purpose Overview

The FSA221UMX is a combined USB 2.0 High-Speed (480 Mbps) and audio switch IC manufactured by onsemi (formerly Fairchild Semiconductor). It features a single Dual-Pole, Double-Throw (DPDT) configuration housed in a 10-pin UMLP (Ultra Mini Leadless Package) surface-mount package. The device operates within a supply voltage range of 3V to 5.5V and supports an operating temperature range of -40°C to +85°C. Key electrical parameters include a typical on-resistance of 4Ω for HS-USB and 3Ω for Audio, with a maximum on-resistance of 6Ω for USB and 5Ω for Audio as per distributor data sheets. The bandwidth is specified at 720 MHz, and the switching time is typically 10 µs.

Audio Special Purpose Feature Summary

• Single DPDT switch configuration combining USB 2.0 Hi-Speed and stereo audio paths
• Low on-resistance: Typical 4Ω (HS-USB), Typical 3Ω (Audio); Max 6Ω (USB), Max 5Ω (Audio)
• High bandwidth of 720 MHz supporting USB 2.0 High-Speed (480 Mbps) data transmission
• Compact 10-UMLP (1.8x1.4 mm x 0.5 mm max height) surface-mount package
• Low power consumption with standby current < 1 µA (typical)

Audio Special Purpose Applications

• Mobile handsets and smartphones
• Media tablets and portable media players
• Consumer audio devices requiring USB/audio sharing
• USB peripherals with integrated audio codecs

Audio Special Purpose Procurement Notes

Verify the specific manufacturer source, as the component appears under both Fairchild and onsemi branding due to corporate acquisition history. Confirm the package designation matches the 10-UMLL or 10-UFQFN specification found in official datasheets. Check current availability status, as some distributors list this part as discontinued or with limited stock. Ensure the ordering suffix corresponds to the required tape and reel or cut tape packaging format.

Audio Special Purpose Selection Notes

Select this component when a low-profile, single-channel DPDT switch is required for USB 2.0 or audio applications. The 720 MHz bandwidth ensures compatibility with high-speed data signals. Verify that the on-resistance meets the signal integrity requirements of the target circuit. The 10-UMLP package is suitable for space-constrained portable designs.