KSC1008OTA Equivalent & Substitute Parts

Part Overview

The KSC1008OTA is an NPN bipolar junction transistor manufactured by onsemi, rated for 60V collector-emitter breakdown voltage and 700mA maximum collector current. This device is packaged in a TO-92-3 through-hole configuration and is designed for general-purpose switching and amplification applications with a maximum power dissipation of 800mW.

The KSC1008OTA is classified as obsolete. Identifying equivalent and substitute parts is necessary to maintain design continuity, ensure supply chain availability, and support ongoing production or repair requirements for systems utilizing this component.

Key Parameters

Parameter	Value	Unit
Transistor Type	NPN	—
Voltage - Collector Emitter Breakdown (Max)	60	V
Current - Collector (Ic) (Max)	700	mA
Power - Max	800	mW
Frequency - Transition	50	MHz
Vce Saturation (Max) @ Ib, Ic	400mV @ 50mA, 500mA	V
DC Current Gain (hFE) (Min) @ Ic, Vce	70 @ 50mA, 2V	—
Mounting Type	Through Hole	—
Package / Case	TO-92-3	—
Operating Temperature (Max)	150	°C

Substitute Part Grouping Explanation

Substitution of the KSC1008OTA is determined by electrical and mechanical compatibility across the following critical parameters:

Electrical Compatibility Criteria:

Transistor type must be NPN
Collector-emitter breakdown voltage must be greater than or equal to 60V
Maximum collector current must be greater than or equal to 700mA
Maximum power dissipation must be greater than or equal to 800mW
Transition frequency must support the intended application frequency range
Saturation voltage characteristics must be compatible with circuit design requirements

Mechanical Compatibility Criteria:

Mounting type must be through-hole
Package must be TO-92-3 or mechanically equivalent form factor

The substitute parts identified below meet these criteria with varying degrees of parameter overlap. Parts are grouped based on their electrical performance relative to the KSC1008OTA baseline specifications.

Parameter Comparison

Parameter	KSC1008OTA	KSC1008YBU	BC337-25-AP	ZTX451
Manufacturer	onsemi	Fairchild Semiconductor	Micro Commercial Co	Diodes Incorporated
Product Status	Obsolete	Active	Obsolete	Active
Transistor Type	NPN	NPN	NPN	NPN
Voltage - Collector Emitter Breakdown (Max)	60V	60V	45V	60V
Current - Collector (Ic) (Max)	700mA	700mA	800mA	1A
Power - Max	800mW	800mW	625mW	1W
Frequency - Transition	50MHz	50MHz	210MHz	150MHz
Vce Saturation (Max) @ Ib, Ic	400mV @ 50mA, 500mA	400mV @ 50mA, 500mA	700mV @ 50mA, 500mA	350mV @ 15mA, 150mA
DC Current Gain (hFE) (Min) @ Ic, Vce	70 @ 50mA, 2V	120 @ 50mA, 2V	160 @ 100mA, 1V	50 @ 150mA, 10V
Mounting Type	Through Hole	Through Hole	Through Hole	Through Hole
Package / Case	TO-92-3	TO-92-3	TO-92	E-Line (TO-92 compatible)
Operating Temperature (Max)	150°C	150°C	150°C	200°C

Engineering Selection Recommendations

KSC1008YBU (Fairchild Semiconductor)

The KSC1008YBU is the closest electrical and mechanical equivalent to the KSC1008OTA. Both devices share identical voltage, current, power, and frequency ratings. The KSC1008YBU is currently in active production status, ensuring long-term supply availability. The primary difference is an increased DC current gain (hFE minimum of 120 versus 70), which may require circuit verification in gain-sensitive applications. This part is recommended as the primary substitute for direct replacement in existing designs.

ZTX451 (Diodes Incorporated)

The ZTX451 exceeds the KSC1008OTA specifications in collector current (1A versus 700mA), power dissipation (1W versus 800mW), and transition frequency (150MHz versus 50MHz). The ZTX451 is in active production and carries RoHS3 compliance certification. The E-Line package is mechanically compatible with TO-92 form factors. This part is suitable for applications requiring enhanced performance margins or higher frequency operation. The lower DC current gain (50 minimum) and different saturation voltage characteristics require circuit validation.

BC337-25-AP (Micro Commercial Co)

The BC337-25-AP has a reduced collector-emitter breakdown voltage rating (45V versus 60V) and lower maximum power dissipation (625mW versus 800mW). This part is classified as obsolete. The BC337-25-AP is not recommended as a substitute for the KSC1008OTA in applications where the full 60V rating is required.

Frequently Asked Questions (FAQ)

Q: Can the KSC1008YBU be used as a direct replacement for the KSC1008OTA?

A: The KSC1008YBU is electrically and mechanically compatible with the KSC1008OTA. Both devices have identical maximum voltage, current, power, and frequency specifications. The KSC1008YBU has a higher minimum DC current gain (120 versus 70), which may affect circuit behavior in applications sensitive to gain variation. Circuit verification is recommended before production implementation.

Q: What is the difference between the TO-92-3 and E-Line packages?

A: The TO-92-3 is a standard three-lead through-hole package with formed leads. The E-Line package used by the ZTX451 is mechanically compatible with TO-92 form factors but may have different lead spacing or material specifications. Physical verification of board layout compatibility is necessary before substitution.

Q: Is the BC337-25-AP suitable for applications requiring 60V operation?

A: No. The BC337-25-AP has a maximum collector-emitter breakdown voltage of 45V, which is below the 60V specification of the KSC1008OTA. This part is not suitable for circuits designed to operate at or near 60V.

Q: Why is the KSC1008OTA classified as obsolete?

A: The KSC1008OTA is no longer in active production by onsemi. The KSC1008YBU from Fairchild Semiconductor serves as the active equivalent product line.

Q: What compliance certifications apply to these substitute parts?

A: The KSC1008YBU does not list RoHS status in the provided specifications. The BC337-25-AP and ZTX451 are both RoHS3 compliant. All parts listed are REACH unaffected and carry EAR99 export classification.

Q: Can the ZTX451 be used in all applications where the KSC1008OTA is specified?

A: The ZTX451 exceeds the KSC1008OTA in maximum ratings (higher current, power, and frequency). However, the lower DC current gain (50 minimum versus 70 minimum) and different saturation voltage characteristics may affect circuit performance. Applications with specific gain or saturation requirements require circuit analysis and testing.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message