FSUSB104UMX USB Switch IC Equivalent & Substitute Parts

Part Overview

The FSUSB104UMX is a USB Switch IC manufactured by onsemi, designed for single-channel USB 2.0 switching applications. This device features a Dual Pole Dual Throw (DPDT) switch configuration in a 10-UMLP surface mount package. The FSUSB104UMX is currently classified as obsolete, making identification of equivalent and substitute parts essential for ongoing design support and production continuity. Active alternatives with compatible electrical and mechanical specifications are available to maintain system functionality.

Substiute Parts

FSUSB104UMX

onsemiIn Stock: 50381FSUSB104UMX Datasheet

Current PartRFQ

FSUSB42UMX

onsemiIn Stock: 285405FSUSB42UMX Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the FSUSB104UMX is determined by strict alignment of the following critical parameters:

Electrical Compatibility Requirements:

• Switch Circuit Type: DPDT configuration
• Number of Channels: 1 channel
• On-State Resistance (Max): 6.5 Ohm
• -3dB Bandwidth: 720 MHz minimum
• Features: USB 2.0 compliance
• Operating Temperature Range: -40°C ~ 85°C (TA)

Mechanical Compatibility Requirements:

• Package / Case: 10-UFQFN
• Supplier Device Package: 10-UMLP (1.8x1.4)
• Mounting Type: Surface Mount

Compliance Requirements:

• RoHS Status: ROHS3 Compliant
• Moisture Sensitivity Level (MSL): 1 (Unlimited)

The FSUSB42UMX meets all specified electrical and mechanical parameters. The primary distinction is the supply voltage range expansion (2.4V ~ 4.4V versus 3V ~ 4.4V) and the switch feature classification (Break-Before-Make versus Bi-Directional), both of which represent functional enhancements compatible with FSUSB104UMX applications.

Parameter Comparison

Engineering Selection Recommendations

The FSUSB42UMX is the primary substitute for the obsolete FSUSB104UMX. Both parts maintain identical electrical performance specifications including on-state resistance, bandwidth, and operating temperature range. Both devices are manufactured by onsemi and comply with ROHS3 and MSL 1 requirements.

The FSUSB42UMX offers expanded supply voltage compatibility (2.4V minimum versus 3V minimum), providing greater flexibility in low-voltage applications. The part is currently in active production status with substantial inventory availability, ensuring long-term supply chain continuity.

Mechanical compatibility is confirmed through identical package specifications (10-UFQFN, 10-UMLP 1.8x1.4), enabling direct board-level substitution without layout modifications.

Frequently Asked Questions (FAQ)

Q: Can the FSUSB42UMX directly replace the FSUSB104UMX on existing PCBs?

A: Yes. Both parts use identical package specifications (10-UFQFN, 10-UMLP 1.8x1.4) and pinout configuration, enabling direct substitution without PCB redesign.

Q: What is the primary difference between these two parts?

A: The FSUSB104UMX is obsolete, while the FSUSB42UMX is in active production. The FSUSB42UMX also supports a lower minimum supply voltage (2.4V versus 3V), making it suitable for a broader range of applications.

Q: Are both parts compliant with the same regulatory standards?

A: Yes. Both the FSUSB104UMX and FSUSB42UMX are ROHS3 compliant with MSL 1 (Unlimited) moisture sensitivity rating.

Q: What is the significance of the switch feature difference (Bi-Directional versus Break-Before-Make)?

A: Both feature classifications are compatible with USB 2.0 switching applications. Break-Before-Make operation in the FSUSB42UMX ensures signal isolation during switching transitions, which is beneficial for applications requiring clean switching without signal overlap.

Q: Is the on-state resistance identical between both parts?

A: Yes. Both parts specify a maximum on-state resistance of 6.5 Ohm, ensuring equivalent signal integrity and power dissipation characteristics.

Q: What is the bandwidth specification and its relevance?

A: Both parts support -3dB bandwidth of 720 MHz, which exceeds USB 2.0 requirements (480 Mbps) and ensures adequate signal fidelity for high-speed USB applications.