FSAT66L6X Equivalent & Substitute Parts

Part Overview

The FSAT66L6X is a single-circuit SPST-NO (Normally Open) IC switch manufactured by onsemi, designed for low-voltage signal switching applications. This component features a 15Ohm on-state resistance and operates across a 1.65V to 5.5V supply range with a maximum switching time of 5.5ns. The part is classified as obsolete, making equivalent substitute parts necessary for new designs and ongoing production requirements.

Key Parameters

Parameter	Value
Manufacturer Part Number	FSAT66L6X
Manufacturer	onsemi
Category	Interface
Switch Circuit Type	SPST - NO
Multiplexer/Demultiplexer Circuit	1:1
Number of Circuits	1
On-State Resistance (Max)	15Ohm
Voltage - Supply, Single (V+)	1.65V ~ 5.5V
Switch Time (Ton, Toff) (Max)	4.5ns, 5.5ns
-3dB Bandwidth	250MHz
Charge Injection	0.05pC
Channel Capacitance (CS(off), CD(off))	6pF
Current - Leakage (IS(off)) (Max)	10µA
Operating Temperature	-40°C ~ 85°C (TA)
Mounting Type	Surface Mount
Package / Case	6-UFDFN
Product Status	Obsolete
Moisture Sensitivity Level (MSL)	1 (Unlimited)

Substitute Part Grouping Explanation

The FSAT66L6X can be substituted with the 74LVC1G66 series parts based on the following critical parameters:

Substitution Criteria:

Switch circuit type: SPST - NO (identical)
Multiplexer/Demultiplexer circuit: 1:1 (identical)
Number of circuits: 1 (identical)
Voltage supply range: 1.65V ~ 5.5V (identical)
Mounting type: Surface Mount (identical)
Moisture Sensitivity Level: 1 (Unlimited) (identical)

The substitute parts 74LVC1G66GM,115 and 74LVC1G66GM,132 are functionally equivalent single-circuit SPST-NO switches with improved electrical performance characteristics and active product status. Both substitute parts maintain the same supply voltage range and circuit topology as the FSAT66L6X, ensuring direct functional compatibility in applications requiring low-voltage signal switching.

Parameter Comparison

Parameter	FSAT66L6X	74LVC1G66GM,115	74LVC1G66GM,132
Manufacturer	onsemi	Nexperia USA Inc.	Nexperia USA Inc.
Switch Circuit	SPST - NO	SPST - NO	SPST - NO
Multiplexer/Demultiplexer Circuit	1:1	1:1	1:1
Number of Circuits	1	1	1
On-State Resistance (Max)	15Ohm	10Ohm	10Ohm
Voltage - Supply, Single (V+)	1.65V ~ 5.5V	1.65V ~ 5.5V	1.65V ~ 5.5V
Switch Time (Ton, Toff) (Max)	4.5ns, 5.5ns	4.2ns, 5ns	4.2ns, 5ns
-3dB Bandwidth	250MHz	500MHz	500MHz
Charge Injection	0.05pC	7.5pC	7.5pC
Channel Capacitance (CS(off), CD(off))	6pF	6.5pF	6.5pF
Current - Leakage (IS(off)) (Max)	10µA	5µA	5µA
Operating Temperature	-40°C ~ 85°C	-40°C ~ 125°C	-40°C ~ 125°C
Mounting Type	Surface Mount	Surface Mount	Surface Mount
Package / Case	6-UFDFN	6-XFDFN	6-XFDFN
Product Status	Obsolete	Active	Active
RoHS Status	Not specified	ROHS3 Compliant	ROHS3 Compliant
Moisture Sensitivity Level (MSL)	1 (Unlimited)	1 (Unlimited)	1 (Unlimited)

Engineering Selection Recommendations

The 74LVC1G66GM,115 and 74LVC1G66GM,132 are direct functional substitutes for the obsolete FSAT66L6X. Both substitute parts are classified as active products with ROHS3 compliance, ensuring long-term availability and regulatory alignment for new designs.

The 74LVC1G66 series offers improved electrical performance compared to the FSAT66L6X, including lower on-state resistance (10Ohm versus 15Ohm), reduced leakage current (5µA versus 10µA), and extended operating temperature range (-40°C to 125°C versus -40°C to 85°C). These enhancements provide superior performance margins in signal switching applications while maintaining identical supply voltage compatibility and circuit topology.

Both substitute part numbers (74LVC1G66GM,115 and 74LVC1G66GM,132) are equivalent alternatives differing only in packaging designation and inventory availability. Selection between these two variants should be based on supply chain requirements and packaging specifications for your manufacturing process.

Frequently Asked Questions (FAQ)

Q: Can the 74LVC1G66GM series directly replace the FSAT66L6X in existing designs?

A: Yes. Both the 74LVC1G66GM,115 and 74LVC1G66GM,132 maintain identical supply voltage range (1.65V ~ 5.5V), circuit topology (SPST-NO, 1:1), and functional characteristics. The substitute parts feature improved electrical performance with lower on-state resistance and leakage current.

Q: What are the package differences between FSAT66L6X and the 74LVC1G66 substitutes?

A: The FSAT66L6X uses a 6-UFDFN package, while the 74LVC1G66 substitutes use a 6-XFDFN package. Both are surface-mount packages with similar form factors suitable for compact PCB layouts. Physical dimensions and pin configurations should be verified against datasheets for PCB redesign requirements.

Q: Are there differences between 74LVC1G66GM,115 and 74LVC1G66GM,132?

A: Both part numbers are functionally identical 74LVC1G66 switches with the same electrical specifications. The differences are in packaging designation (Tape & Reel variants) and current inventory levels. Selection should be based on your supply chain and manufacturing packaging requirements.

Q: What is the operating temperature difference between the FSAT66L6X and substitute parts?

A: The FSAT66L6X operates from -40°C to 85°C, while the 74LVC1G66 substitutes operate from -40°C to 125°C. The extended upper temperature limit of the substitute parts provides additional thermal margin for applications in elevated-temperature environments.

Q: Are the substitute parts RoHS compliant?

A: Yes. The 74LVC1G66GM,115 and 74LVC1G66GM,132 are ROHS3 compliant. The FSAT66L6X RoHS status is not specified in the provided data.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message