ZTX651STOB Equivalent & Substitute Parts

Part Overview

The ZTX651STOB is a Bipolar (BJT) NPN transistor manufactured by Diodes Incorporated, designed for general-purpose switching and amplification applications. This device features a 60 V collector-emitter breakdown voltage, 2 A maximum collector current, and 1 W power dissipation capability in a Through Hole E-Line (TO-92 compatible) package.

The ZTX651STOB is classified as an obsolete product. Identification of equivalent and substitute parts is necessary to support ongoing maintenance, repair, and redesign activities for legacy systems and equipment utilizing this component.

Substiute Parts

ZTX651STOB

Diodes IncorporatedIn Stock: 1043ZTX651STOB Datasheet

Current PartRFQ

ZTX651

Diodes IncorporatedIn Stock: 30129ZTX651 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the ZTX651STOB is determined by electrical and mechanical parameter equivalence across the following criteria:

Electrical Parameters:

• Transistor type (NPN)
• Maximum collector current (2 A)
• Maximum collector-emitter breakdown voltage (60 V)
• Saturation voltage characteristics (500mV @ 200mA, 2A)
• Collector cutoff current (100nA maximum)
• Power dissipation capability (1 W)
• Transition frequency (175MHz)
• Operating temperature range (-55°C to 200°C)

Mechanical Parameters:

• Mounting type (Through Hole)
• Package form factor (E-Line-3, TO-92 compatible)

Compliance Parameters:

• RoHS3 compliance
• Moisture sensitivity level (MSL 1)

Substitute parts must match all electrical specifications and maintain physical and thermal compatibility within the specified package envelope.

Parameter Comparison

Engineering Selection Recommendations

The ZTX651 (Bulk packaging) is the direct substitute for the ZTX651STOB. Both parts are manufactured by Diodes Incorporated and share identical electrical specifications and thermal operating ranges.

Selection Basis:

The ZTX651 substitute part maintains full electrical and mechanical compatibility with the ZTX651STOB across all specified parameters. The primary distinction is product status: the ZTX651STOB is obsolete, while the ZTX651 is an active product with current manufacturing support and availability (30,100 pieces in stock versus 1,027 pieces for the obsolete variant).

Both parts carry ROHS3 compliance certification and MSL 1 rating, ensuring environmental and moisture handling requirements are equivalent. The E-Line-3 package form factor and Through Hole mounting type are maintained, supporting direct mechanical and thermal integration into existing circuit designs.

The ZTX651 is suitable for new designs, redesigns, and ongoing production support of systems originally specified with the ZTX651STOB.

Frequently Asked Questions (FAQ)

Q: Can the ZTX651 directly replace the ZTX651STOB in existing applications?

A: Yes. The ZTX651 is electrically and mechanically equivalent to the ZTX651STOB. All electrical parameters, including collector current, breakdown voltage, saturation characteristics, and operating temperature range, are identical. The Through Hole E-Line-3 package form factor is compatible with existing PCB layouts and component mounting specifications.

Q: What is the primary reason for substitution?

A: The ZTX651STOB is classified as an obsolete product. The ZTX651 is the active equivalent part from the same manufacturer, ensuring continued availability and manufacturing support for legacy system maintenance and new production requirements.

Q: Are there packaging differences between the ZTX651STOB and ZTX651?

A: The ZTX651STOB is supplied with formed leads, while the ZTX651 is supplied in bulk packaging. Both use the E-Line-3 package form factor compatible with TO-92 pinout standards. The physical dimensions and lead configuration remain consistent for direct circuit board integration.

Q: Do both parts meet the same compliance standards?

A: Yes. Both the ZTX651STOB and ZTX651 are ROHS3 compliant and carry MSL 1 (Unlimited) moisture sensitivity ratings. Environmental and regulatory compliance requirements are equivalent.

Q: What is the inventory status difference?

A: The ZTX651STOB (obsolete) has 1,027 pieces in stock. The ZTX651 (active) has 30,100 pieces in stock, providing greater availability for ongoing production and support applications.

Q: Are the thermal and frequency characteristics identical?

A: Yes. Both parts operate across the identical temperature range (-55°C to 200°C junction temperature) and share the same transition frequency specification (175MHz). Thermal design and frequency-dependent circuit performance remain unchanged.