FSM4J Equivalent & Substitute Parts

Part Overview

The FSM4J is a tactile switch manufactured by TE Connectivity ALCOSWITCH Switches, configured as a SPST-NO (Single Pole Single Throw Normally Open) momentary contact switch. The switch is rated for 0.05A at 24VDC with a top-actuated through-hole mounting design and a 5.00mm actuator height. The FSM4J is classified as obsolete, making identification of equivalent and substitute parts necessary for ongoing design support, maintenance, and production continuity. Substitute parts must maintain electrical compatibility, mechanical interchangeability, and functional equivalence while meeting current availability and compliance requirements.

Substiute Parts

FSM4J

TE Connectivity ALCOSWITCH SwitchesIn Stock: 925FSM4J Datasheet

Current PartRFQ

1825910-6

TE Connectivity ALCOSWITCH SwitchesIn Stock: 22601825910-6 Datasheet

DirectRFQ

TL1105AF160Q

E-SwitchIn Stock: 20688TL1105AF160Q Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the FSM4J are identified based on strict electrical and mechanical parameter matching. The following criteria determine substitution eligibility:

Critical Parameters (Must Match Exactly):

• Circuit configuration must be SPST-NO
• Contact rating must support 0.05A at the specified voltage
• Switch function must be Off-Mom (momentary contact)
• Mounting type must be through-hole
• Actuator height must be 5.00mm vertical
• Actuator orientation must be top-actuated
• Outline dimensions must be 6.00mm x 6.00mm
• Termination style must be PC Pin

Important Parameters (Must Be Equal or Exceed):

• Operating force of 160gf
• Switch travel of 0.25mm
• Mechanical life of 100,000 cycles
• Operating temperature range must encompass or exceed -20°C ~ 70°C

Substitute parts are grouped into two categories based on voltage rating compatibility and product status. Parts with higher voltage ratings or extended temperature ranges are acceptable substitutes. Parts with active product status are preferred over obsolete designations for long-term availability.

Parameter Comparison

Engineering Selection Recommendations

Primary Substitute: 1825910-6 (TE Connectivity ALCOSWITCH Switches)

The 1825910-6 is the preferred substitute for the obsolete FSM4J. Both parts are manufactured by TE Connectivity ALCOSWITCH Switches and share identical electrical specifications (0.05A @ 24VDC) and mechanical dimensions. The 1825910-6 offers an extended operating temperature range (-35°C ~ 85°C) compared to the FSM4J (-20°C ~ 70°C), providing superior performance in extreme temperature environments. The 1825910-6 is classified as active product status with ROHS3 compliance and MSL 1 rating, ensuring long-term availability and regulatory compliance. The actuator material differs (PBT versus Polyester), but both materials meet the specified mechanical requirements. This substitute provides direct functional equivalence with enhanced environmental specifications.

Secondary Substitute: TL1105AF160Q (E-Switch)

The TL1105AF160Q from E-Switch is a mechanically and functionally compatible substitute with identical physical dimensions, actuator height, operating force, and switch travel. The TL1105AF160Q is classified as active product status with ROHS3 compliance and MSL 1 rating. The contact rating differs at 0.05A @ 12VDC, which is lower than the FSM4J specification of 0.05A @ 24VDC. The TL1105AF160Q is suitable for applications operating at 12VDC or lower voltage levels. The operating temperature range matches the FSM4J (-20°C ~ 70°C). The actuator material is Polyamide (PA) Nylon, which meets mechanical specifications. This substitute is appropriate for 12VDC circuit designs requiring mechanical and dimensional compatibility with the FSM4J footprint.

Selection Criteria:

For 24VDC applications, select 1825910-6. For 12VDC applications, either 1825910-6 or TL1105AF160Q are acceptable; 1825910-6 is preferred for design consistency within the TE Connectivity product family. Verify circuit voltage requirements before final part selection.

Frequently Asked Questions (FAQ)

Q: Can the 1825910-6 directly replace the FSM4J in existing designs?

A: Yes. The 1825910-6 is mechanically and electrically compatible with the FSM4J. Both parts share identical contact ratings (0.05A @ 24VDC), circuit configuration (SPST-NO), mounting type (through-hole), and physical dimensions (6.00mm x 6.00mm with 5.00mm actuator height). The 1825910-6 provides extended operating temperature range and active product status, making it a direct replacement.

Q: What is the voltage difference between the FSM4J and TL1105AF160Q?

A: The FSM4J is rated for 0.05A @ 24VDC, while the TL1105AF160Q is rated for 0.05A @ 12VDC. The TL1105AF160Q is suitable for 12VDC applications only. For 24VDC circuits, use the 1825910-6 substitute.

Q: Are all three parts mechanically interchangeable?

A: Yes. All three parts (FSM4J, 1825910-6, and TL1105AF160Q) share identical mechanical specifications: 6.00mm x 6.00mm outline, 5.00mm vertical actuator height, top-actuated orientation, through-hole mounting, PC pin termination, 160gf operating force, 0.25mm switch travel, and 100,000 cycle mechanical life. Mechanical interchangeability is confirmed across all three parts.

Q: What is the difference in actuator material between the substitutes?

A: The FSM4J uses Polyester, the 1825910-6 uses Polybutylene Terephthalate (PBT), and the TL1105AF160Q uses Polyamide (PA) Nylon. All three materials meet the specified mechanical requirements (160gf operating force, 0.25mm travel, 100,000 cycles). Material selection does not affect functional compatibility for the specified electrical and mechanical parameters.

Q: Why is the FSM4J classified as obsolete?

A: The FSM4J is an older product designation that has been superseded by newer part numbers. The 1825910-6 represents the current active equivalent from TE Connectivity ALCOSWITCH Switches with improved specifications and compliance certifications.

Q: Are the substitute parts RoHS compliant?

A: Yes. Both 1825910-6 and TL1105AF160Q are ROHS3 compliant. The FSM4J RoHS status is not specified in the provided data.

Q: What is the packaging difference between the main part and substitutes?

A: The FSM4J is packaged in standard format (packaging designation not specified). The 1825910-6 and TL1105AF160Q are supplied in bulk packaging. Verify packaging requirements for your procurement process.

Q: Can the TL1105AF160Q be used in a 24VDC circuit?

A: No. The TL1105AF160Q is rated for 0.05A @ 12VDC maximum. Using it in a 24VDC circuit exceeds the contact rating and may result in switch failure or unsafe operation. For 24VDC applications, use the 1825910-6.

Q: What is the operating temperature range difference?

A: The FSM4J and TL1105AF160Q both operate from -20°C to 70°C. The 1825910-6 extends this range to -35°C to 85°C, providing superior performance in extreme temperature environments. For applications requiring extended temperature operation, the 1825910-6 is the preferred choice.

Q: Are all parts REACH compliant?

A: Yes. All three parts (FSM4J, 1825910-6, and TL1105AF160Q) are classified as REACH Unaffected, indicating compliance with REACH regulations.