ZTX705STOB Equivalent & Substitute Parts

Part Overview

The ZTX705STOB is a PNP Darlington bipolar junction transistor manufactured by Diodes Incorporated, designed for general-purpose switching and amplification applications. This component features a maximum collector current of 1 A, collector-emitter breakdown voltage of 120 V, and a transition frequency of 160 MHz. The device is packaged in an E-Line (TO-92 compatible) through-hole configuration with formed leads.

The ZTX705STOB is classified as obsolete. Identifying equivalent substitute parts is necessary to maintain design continuity, ensure component availability for production, and support long-term system maintenance and repair operations.

Substiute Parts

ZTX705STOB

Diodes IncorporatedIn Stock: 826ZTX705STOB Datasheet

Current PartRFQ

ZTX705STZ

Diodes IncorporatedIn Stock: 3889ZTX705STZ Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the ZTX705STOB is determined by strict equivalence across all critical electrical and mechanical parameters. The substitute part must satisfy the following criteria:

Electrical Parameters (Must Match Exactly):

• Transistor type: PNP - Darlington configuration
• Maximum collector current: 1 A
• Collector-emitter breakdown voltage: 120 V
• Vce saturation: 2.5 V @ 2mA, 2A
• Collector cutoff current: 10 µA
• DC current gain (hFE): 3000 minimum @ 1A, 5V
• Transition frequency: 160 MHz
• Maximum power dissipation: 1 W
• Operating temperature range: -55°C to 200°C (TJ)

Mechanical Parameters (Must Match Exactly):

• Mounting type: Through Hole
• Package / Case: E-Line-3, Formed Leads
• Supplier device package: E-Line (TO-92 compatible)

Compliance Parameters (Must Match Exactly):

• RoHS Status: ROHS3 Compliant
• Moisture Sensitivity Level: 1 (Unlimited)
• REACH Status: REACH Unaffected

The substitute part ZTX705STZ meets all specified criteria and is therefore a direct functional equivalent.

Parameter Comparison

Engineering Selection Recommendations

The ZTX705STZ is a direct electrical and mechanical equivalent to the ZTX705STOB. Both components are manufactured by Diodes Incorporated and share identical electrical specifications, operating parameters, and compliance certifications.

The primary distinction between these parts is product status and packaging format. The ZTX705STOB is classified as obsolete, while the ZTX705STZ maintains active product status with higher inventory availability (3800 pieces in stock versus 748 pieces). The ZTX705STZ is supplied in Tape & Box (TB) packaging, whereas the ZTX705STOB packaging format is not specified in the provided data.

For new designs and production applications, the ZTX705STZ is the appropriate selection due to its active status and assured long-term availability. For legacy system repairs or maintenance requiring exact packaging compatibility, component-level verification of the original ZTX705STOB packaging format is necessary prior to substitution.

Both parts satisfy ROHS3 compliance, REACH unaffected status, and MSL 1 (unlimited) moisture sensitivity requirements, ensuring compatibility with standard manufacturing and storage protocols.

Frequently Asked Questions (FAQ)

Q: Can the ZTX705STZ be used as a direct replacement for the ZTX705STOB in existing circuit designs?

A: Yes. The ZTX705STZ is electrically and mechanically equivalent to the ZTX705STOB. All electrical parameters, including collector current, breakdown voltage, saturation characteristics, current gain, and frequency response, are identical. Both components use the same E-Line (TO-92 compatible) through-hole package with formed leads, ensuring pin-for-pin compatibility and identical PCB footprints.

Q: What is the significance of the product status difference between these parts?

A: The ZTX705STOB is classified as obsolete, indicating that Diodes Incorporated no longer manufactures this variant. The ZTX705STZ maintains active product status, meaning it is currently in production and subject to ongoing quality assurance and supply chain management. For production applications, the active status of the ZTX705STZ ensures component availability and compliance with current manufacturing standards.

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

A: No. Both the ZTX705STOB and ZTX705STZ are ROHS3 compliant, REACH unaffected, and classified as MSL 1 (unlimited moisture sensitivity). These certifications are identical across both parts, ensuring compatibility with standard manufacturing processes and regulatory requirements.

Q: What is the difference in packaging between these parts?

A: The ZTX705STZ is supplied in Tape & Box (TB) packaging format, which is standard for automated assembly and high-volume production. The packaging format of the ZTX705STOB is not specified in the provided technical data. For applications requiring specific packaging formats, the packaging type should be verified against original component documentation or procurement specifications.

Q: Are the electrical characteristics guaranteed to be identical between these parts?

A: Yes. Both parts share the same base product number (ZTX705) and are manufactured by Diodes Incorporated. All specified electrical parameters—including maximum collector current (1 A), collector-emitter breakdown voltage (120 V), saturation voltage (2.5 V @ 2mA, 2A), DC current gain (3000 @ 1A, 5V), transition frequency (160 MHz), and operating temperature range (-55°C to 200°C)—are identical. These parameters are guaranteed by the manufacturer's specifications.

Q: Can the ZTX705STZ be used in high-temperature applications?

A: Yes. The ZTX705STZ is rated for operation across the temperature range of -55°C to 200°C (junction temperature), which is identical to the ZTX705STOB. This rating supports applications requiring extended temperature operation within the specified range.

Q: Is the ZTX705STZ suitable for automated assembly processes?

A: Yes. The ZTX705STZ is supplied in Tape & Box (TB) packaging, which is designed for automated pick-and-place assembly equipment. This packaging format is standard for high-volume production environments and is compatible with standard SMT and through-hole assembly processes.