FST3125DR2G Equivalent & Substitute Parts

Part Overview

The FST3125DR2G is a bus switch IC manufactured by onsemi, designed for 1 x 1:1 switching applications in 14-SOIC surface mount packaging. This component operates with a single supply voltage between 4V and 5.5V, supporting a wide operating temperature range of -55°C to 125°C. The part is classified as obsolete, making identification of compatible substitute components essential for ongoing design support and procurement planning.

Substiute Parts

FST3125DR2G

onsemiIn Stock: 1993FST3125DR2G Datasheet

Current PartRFQ

FST3126DR2G

onsemiIn Stock: 2246FST3126DR2G Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

The FST3125DR2G has one identified parametric equivalent: FST3126DR2G. This substitution is valid based on the following matching electrical and mechanical parameters:

• Circuit configuration: Both parts feature 1 x 1:1 bus switch topology with 4 independent circuits
• Voltage supply specification: Both operate within 4V ~ 5.5V single supply range
• Operating temperature range: Both support -55°C ~ 125°C
• Package / Case: Both use 14-SOIC (0.154", 3.90mm Width) surface mount packaging
• Supplier device package: Both specified as 14-SOIC
• Compliance standards: Both are ROHS3 compliant with MSL 1 (Unlimited) rating

The primary difference between these parts is the packaging format: FST3125DR2G is supplied in Cut Tape (CT), while FST3126DR2G is supplied in Tape & Reel (TR). This distinction affects procurement and assembly processes but does not impact electrical or mechanical compatibility.

Parameter Comparison

Engineering Selection Recommendations

Both FST3125DR2G and FST3126DR2G are classified as obsolete products. Selection between these parts should be based on procurement requirements and assembly processes rather than electrical performance, as they are electrically and mechanically identical.

FST3125DR2G in Cut Tape packaging is suitable for low-volume applications, prototype development, or situations requiring individual component handling. FST3126DR2G in Tape & Reel packaging is appropriate for high-volume production runs and automated assembly processes.

Both parts maintain ROHS3 compliance and unlimited moisture sensitivity rating (MSL 1), ensuring compatibility with standard manufacturing and storage protocols. The identical operating specifications guarantee direct functional interchangeability in circuit applications.

Frequently Asked Questions (FAQ)

Q: Can FST3126DR2G replace FST3125DR2G in existing designs?

A: Yes. Both parts are electrically and mechanically identical, with matching voltage supply ranges (4V ~ 5.5V), operating temperature specifications (-55°C ~ 125°C), and 14-SOIC packaging. The only difference is the packaging format (Cut Tape versus Tape & Reel).

Q: What is the significance of the packaging format difference?

A: Cut Tape (CT) packaging supplies individual components on tape for manual or low-volume pick-and-place operations. Tape & Reel (TR) packaging provides components on continuous reels optimized for high-speed automated assembly equipment. Electrical performance is identical.

Q: Are there any compliance or certification differences between these parts?

A: No. Both FST3125DR2G and FST3126DR2G carry identical ROHS3 compliance status, MSL 1 (Unlimited) moisture sensitivity rating, REACH unaffected status, and EAR99 export classification.

Q: Why are both parts listed as obsolete?

A: Obsolete status indicates these components are no longer in active production by the manufacturer. For new designs or long-term production requirements, consultation with component distributors regarding availability and alternative current-generation bus switch solutions is recommended.

Q: Can these parts be used interchangeably on the same PCB assembly?

A: Yes, from an electrical and mechanical standpoint. However, assembly process considerations may apply: Cut Tape format requires manual component placement or compatible pick-and-place equipment, while Tape & Reel format integrates with standard high-volume production lines.