FMMT491-TP Equivalent & Substitute Parts

Part Overview

The FMMT491-TP is an NPN bipolar junction transistor manufactured by Micro Commercial Co, designed for general-purpose switching and amplification applications. This surface mount device operates at 60 V collector-emitter breakdown voltage with a maximum collector current of 1 A and 500 mW power dissipation. The part is classified as Active product status with full RoHS3 compliance and unlimited moisture sensitivity rating. Substitute parts are identified when equivalent electrical performance and mechanical compatibility are required due to inventory constraints, manufacturing discontinuation, or design flexibility needs.

Substiute Parts

FMMT491-TP

Micro Commercial CoIn Stock: 873FMMT491-TP Datasheet

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DNBT8105-7

Diodes IncorporatedIn Stock: 110334DNBT8105-7 Datasheet

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FMMT493ATA

Diodes IncorporatedIn Stock: 48388FMMT493ATA Datasheet

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NSS40201LT1G

onsemiIn Stock: 9145NSS40201LT1G Datasheet

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Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the FMMT491-TP is determined by the following critical parameters:

Primary Substitution Criteria:

• Transistor Type: NPN configuration required
• Voltage - Collector Emitter Breakdown (Max): Minimum 60 V
• Current - Collector (Ic) (Max): Minimum 1 A
• Frequency - Transition: Minimum 150 MHz
• Package / Case: SOT-23-3 (TO-236-3, SC-59) surface mount
• Operating Temperature Range: -55°C to 150°C minimum
• RoHS3 Compliance: Required
• Mounting Type: Surface Mount

Secondary Compatibility Factors:

• Vce Saturation characteristics at specified test conditions
• DC Current Gain (hFE) performance envelope
• Power dissipation capability
• Moisture Sensitivity Level (MSL): Level 1 preferred

Parts meeting all primary criteria are classified as direct substitutes. Parts exceeding specified parameters in current, voltage, or power ratings are classified as functional upgrades suitable for direct replacement.

Parameter Comparison

Engineering Selection Recommendations

DNBT8105-7 (Diodes Incorporated)

The DNBT8105-7 qualifies as a direct substitute for the FMMT491-TP. Both devices share identical electrical specifications for voltage breakdown (60 V), collector current (1 A), transition frequency (150 MHz), saturation voltage, and current gain parameters. The DNBT8105-7 provides 600 mW power dissipation, exceeding the 500 mW specification of the main part. Both devices maintain Active product status with full RoHS3 compliance and MSL Level 1 rating. The primary difference is packaging format: DNBT8105-7 is supplied in Cut Tape and Digi-Reel format versus Tape & Reel for FMMT491-TP. This substitute is suitable for direct replacement in all applications where the main part is specified.

FMMT493ATA (Diodes Incorporated)

The FMMT493ATA qualifies as a direct substitute for the FMMT491-TP. Both devices share identical voltage breakdown (60 V), collector current (1 A), power dissipation (500 mW), and transition frequency (150 MHz) specifications. The FMMT493ATA exhibits higher DC current gain (300 @ 250mA, 10V) compared to the main part (100 @ 500mA, 5V), representing enhanced amplification capability. Both devices maintain Active product status with full RoHS3 compliance and MSL Level 1 rating. Packaging format is Tape & Reel for both parts. This substitute is suitable for direct replacement in all applications where the main part is specified.

NSS40201LT1G (onsemi)

The NSS40201LT1G is a functional upgrade substitute for the FMMT491-TP. This device exceeds the main part specifications in collector current (2 A versus 1 A) and provides enhanced current handling capability. However, the NSS40201LT1G operates at a reduced voltage breakdown rating of 40 V compared to the 60 V specification of FMMT491-TP. This voltage limitation restricts substitution to applications where the circuit design operates below 40 V collector-emitter voltage. The NSS40201LT1G maintains identical transition frequency (150 MHz), operating temperature range (-55 to 150°C), and compliance certifications (RoHS3, MSL Level 1). This substitute is suitable for replacement only in applications where the maximum circuit voltage does not exceed 40 V.

Frequently Asked Questions (FAQ)

Q: Can DNBT8105-7 be used as a direct replacement for FMMT491-TP?

A: Yes. The DNBT8105-7 meets all primary substitution criteria with identical voltage breakdown (60 V), collector current (1 A), transition frequency (150 MHz), and saturation characteristics. The 600 mW power rating exceeds the 500 mW specification, providing additional thermal margin. Both devices are RoHS3 compliant with MSL Level 1 rating and identical operating temperature range. The only difference is packaging format (Cut Tape & Digi-Reel versus Tape & Reel).

Q: What is the difference between FMMT493ATA and FMMT491-TP?

A: Both parts share identical voltage (60 V), current (1 A), power (500 mW), and frequency (150 MHz) specifications. The FMMT493ATA exhibits higher DC current gain (300 @ 250mA, 10V) versus the main part (100 @ 500mA, 5V). This higher gain makes FMMT493ATA suitable for applications requiring greater amplification. Both parts are direct substitutes with identical compliance and packaging format (Tape & Reel).

Q: Can NSS40201LT1G replace FMMT491-TP in all applications?

A: No. The NSS40201LT1G operates at 40 V maximum collector-emitter breakdown voltage, which is 20 V lower than the FMMT491-TP specification of 60 V. This device is suitable only for applications where the circuit design operates below 40 V. The NSS40201LT1G provides higher collector current (2 A) and lower saturation voltage (115 mV), making it a functional upgrade for low-voltage, high-current applications within the 40 V limit.

Q: Are all substitute parts available in the same packaging format as FMMT491-TP?

A: No. FMMT491-TP is supplied in Tape & Reel (TR) format. FMMT493ATA is also supplied in Tape & Reel format. DNBT8105-7 and NSS40201LT1G are supplied in Cut Tape (CT) and Digi-Reel format. All parts use identical SOT-23-3 surface mount package, ensuring mechanical compatibility on PCBs. Packaging format differences affect only component handling and reel specifications, not electrical performance or board-level compatibility.

Q: Do all substitute parts meet RoHS3 compliance?

A: Yes. DNBT8105-7, FMMT493ATA, and NSS40201LT1G all maintain RoHS3 compliance identical to FMMT491-TP. All parts are classified as REACH Unaffected with EAR99 export classification and identical HTSUS code (8541.21.0075). All devices carry MSL Level 1 (Unlimited) moisture sensitivity rating.

Q: What is the primary reason to select DNBT8105-7 over FMMT491-TP?

A: DNBT8105-7 provides identical electrical performance with 600 mW power dissipation versus 500 mW for FMMT491-TP, offering 20% additional thermal headroom. Selection is driven by inventory availability, supply chain considerations, or design flexibility requirements. Both parts are electrically equivalent for all specified parameters.

Q: When should NSS40201LT1G be selected instead of FMMT491-TP?

A: NSS40201LT1G is selected for applications requiring higher collector current (2 A versus 1 A) and lower saturation voltage (115 mV versus 500 mV). Selection is restricted to circuit designs operating at maximum 40 V collector-emitter voltage. The lower saturation voltage provides reduced power dissipation in saturated switching applications, making this device suitable for high-current, low-voltage switching circuits.

Q: Are the DC current gain specifications interchangeable between FMMT491-TP and FMMT493ATA?

A: No. FMMT491-TP specifies minimum DC current gain of 100 @ 500mA, 5V. FMMT493ATA specifies minimum DC current gain of 300 @ 250mA, 10V. These are measured at different operating points. FMMT493ATA exhibits higher gain, which may affect circuit biasing in applications sensitive to current gain variation. Circuit designs should be verified for compatibility with the higher gain characteristic of FMMT493ATA.