KSC1674RBU Equivalent & Substitute Parts

Part Overview

The KSC1674RBU is an RF transistor manufactured by onsemi, classified as a bipolar NPN transistor designed for radio frequency applications. This device operates at a transition frequency of 600MHz with a maximum collector-emitter breakdown voltage of 20V and maximum power dissipation of 250mW. The KSC1674RBU is packaged in a through-hole TO-92-3 configuration and is currently listed as obsolete. Due to its obsolete status and limited availability in new production, identifying equivalent substitute parts is necessary for ongoing design support and component procurement.

Key Parameters

Parameter	Value	Unit
Transistor Type	NPN	—
Voltage - Collector Emitter Breakdown (Max)	20	V
Frequency - Transition	600	MHz
Power - Max	250	mW
Current - Collector (Ic) (Max)	20	mA
DC Current Gain (hFE) (Min)	40	@ 1mA, 6V
Noise Figure (dB Typ)	3–5	dB @ 100MHz
Operating Temperature (TJ)	150	°C
Mounting Type	Through Hole	—
Package / Case	TO-92-3	—

Substitute Part Grouping Explanation

Substitution of the KSC1674RBU is determined by the following electrical and mechanical parameters:

Primary Substitution Criteria:

Transistor Type: NPN configuration required
Voltage Rating: Collector-emitter breakdown voltage must meet or exceed 20V
Frequency Performance: Transition frequency must support 600MHz operation
Power Dissipation: Maximum power rating must accommodate 250mW
Current Capability: Maximum collector current must support 20mA operation
DC Current Gain: Minimum hFE must meet or exceed 40 at specified conditions
Operating Temperature: Must support 150°C junction temperature

The substitute part BFP740H6327XTSA1 is listed as an equivalent based on the manufacturer's substitution data provided in the input parameters. This part maintains NPN transistor topology and operates within compatible electrical specifications for RF applications, though it features different packaging (surface mount SOT-343 versus through-hole TO-92-3) and enhanced frequency performance characteristics.

Parameter Comparison

Parameter	KSC1674RBU (Main)	BFP740H6327XTSA1 (Substitute)	Unit
Manufacturer	onsemi	Infineon Technologies	—
Transistor Type	NPN	NPN	—
Voltage - Collector Emitter Breakdown (Max)	20	4.7	V
Frequency - Transition	600	42000	MHz
Power - Max	250	160	mW
Current - Collector (Ic) (Max)	20	30	mA
DC Current Gain (hFE) (Min)	40 @ 1mA, 6V	160 @ 25mA, 3V	—
Operating Temperature (TJ)	150	150	°C
Mounting Type	Through Hole	Surface Mount	—
Package / Case	TO-92-3	SOT-343	—
Product Status	Obsolete	Active	—

Engineering Selection Recommendations

Product Status Consideration: The KSC1674RBU is classified as obsolete, while the BFP740H6327XTSA1 is active in production. For new designs or ongoing component procurement, the active status of BFP740H6327XTSA1 provides supply chain continuity and long-term availability.

Compliance and Certifications: Both parts carry identical REACH and ECCN classifications (REACH Unaffected, EAR99), indicating equivalent regulatory standing. The BFP740H6327XTSA1 carries RoHS3 compliance certification, providing additional environmental compliance assurance for applications subject to RoHS requirements.

Moisture Sensitivity: Both parts are classified as MSL 1 (Unlimited), indicating no moisture sensitivity constraints during storage or handling.

Packaging Implications: The primary difference between these parts is the mounting technology. The KSC1674RBU uses through-hole TO-92-3 packaging, while the BFP740H6327XTSA1 uses surface-mount SOT-343 packaging. This difference requires circuit board redesign and assembly process modification. Selection between these parts depends on whether the application can accommodate surface-mount technology or requires through-hole mounting.

Frequently Asked Questions (FAQ)

Q: Can the BFP740H6327XTSA1 directly replace the KSC1674RBU in existing circuit boards?

A: Direct board-level replacement is not possible due to different mounting technologies. The KSC1674RBU uses through-hole TO-92-3 packaging, while the BFP740H6327XTSA1 uses surface-mount SOT-343 packaging. Circuit board redesign and assembly process modification are required.

Q: What are the key electrical differences between these parts?

A: The BFP740H6327XTSA1 operates at significantly higher transition frequency (42GHz versus 600MHz) and has lower maximum collector-emitter breakdown voltage (4.7V versus 20V). The BFP740H6327XTSA1 supports higher maximum collector current (30mA versus 20mA) and higher DC current gain (160 versus 40). Maximum power dissipation is lower in the substitute (160mW versus 250mW).

Q: Is the BFP740H6327XTSA1 suitable for applications originally designed for the KSC1674RBU?

A: Suitability depends on specific application requirements. The lower voltage rating (4.7V) of the BFP740H6327XTSA1 may not be compatible with circuits designed for 20V operation. The significantly higher frequency capability of the BFP740H6327XTSA1 exceeds the 600MHz requirement of the original design. Detailed circuit analysis is required to determine compatibility.

Q: What is the inventory status of these parts?

A: The KSC1674RBU has 703 pieces in stock as new original inventory. The BFP740H6327XTSA1 has 14,215 pieces in stock as new original inventory, providing superior supply availability.

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

A: Both parts share identical REACH and ECCN classifications. The BFP740H6327XTSA1 carries RoHS3 compliance certification, while the KSC1674RBU does not specify RoHS compliance. Both parts have unlimited moisture sensitivity level (MSL 1).

Q: What mounting considerations apply to the BFP740H6327XTSA1?

A: The BFP740H6327XTSA1 is supplied in Cut Tape (CT) and Digi-Reel packaging formats suitable for automated surface-mount assembly. The device package is PG-SOT343-4-2, requiring surface-mount soldering equipment and techniques.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message