ZTX758STZ Equivalent & Substitute Parts

Part Overview

The ZTX758STZ is an active PNP bipolar junction transistor manufactured by Diodes Incorporated, designed for general-purpose switching and amplification applications. This device features a 400 V collector-emitter breakdown voltage rating, 500 mA maximum collector current, and 1 W power dissipation capability in a Through Hole E-Line (TO-92 compatible) package. The ZTX758STZ is RoHS3 compliant and carries REACH Unaffected status, making it suitable for modern electronic applications requiring environmental compliance. Substitute parts are identified when equivalent electrical performance can be achieved within the specified parameter tolerances while maintaining functional compatibility in the target application circuit.

Substiute Parts

ZTX758STZ

Diodes IncorporatedIn Stock: 10111ZTX758STZ Datasheet

Current PartRFQ

KSP92BU

Fairchild SemiconductorIn Stock: 105474KSP92BU Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the ZTX758STZ is determined by equivalence in the following critical electrical and mechanical parameters:

Electrical Compatibility Criteria:

• Transistor polarity must be PNP
• Maximum collector current must be equal to or greater than 500 mA
• Collector-emitter breakdown voltage must be equal to or greater than 400 V
• Transition frequency must be equal to or greater than 50 MHz
• Maximum power dissipation must support the application requirements

Mechanical Compatibility Criteria:

• Mounting type must be Through Hole
• Package must be physically compatible with TO-92 or E-Line footprints
• Lead configuration must accommodate existing PCB layouts

Compliance Criteria:

• Active product status required
• RoHS compliance status must be documented

The KSP92BU from Fairchild Semiconductor is identified as a substitute part. However, this part exhibits a reduced collector-emitter breakdown voltage (300 V versus 400 V) and lower maximum power dissipation (625 mW versus 1 W). These reductions represent derating from the original specification and require circuit-level evaluation to confirm suitability for the intended application.

Parameter Comparison

Engineering Selection Recommendations

Primary Selection: ZTX758STZ

The ZTX758STZ remains the preferred component for applications requiring the full 400 V collector-emitter breakdown voltage specification and 1 W power dissipation capability. This part is actively manufactured by Diodes Incorporated, maintains RoHS3 compliance, and is available in high inventory quantities (10,100 pieces). The extended operating temperature range (−55°C to +200°C) supports demanding thermal environments.

Substitute Selection: KSP92BU

The KSP92BU from Fairchild Semiconductor is electrically compatible for applications where the circuit design operates below 300 V collector-emitter voltage and power dissipation remains below 625 mW. Both parts share identical collector current ratings (500 mA), transition frequency (50 MHz), and Through Hole mounting configuration. The KSP92BU is actively manufactured and available in substantial inventory (105,400 pieces). Physical package compatibility between E-Line-3 and TO-92-3 allows direct footprint substitution on standard PCB layouts.

Compliance Status:

Both parts carry active product status and meet environmental compliance requirements. The ZTX758STZ holds ROHS3 Compliant and REACH Unaffected designations. The KSP92BU maintains EAR99 export classification, consistent with the primary part.

Frequently Asked Questions (FAQ)

Q: Can the KSP92BU directly replace the ZTX758STZ in all applications?

A: Direct replacement is limited to applications where circuit design operates at collector-emitter voltages not exceeding 300 V and power dissipation remains below 625 mW. Applications utilizing the full 400 V voltage rating or 1 W power capability require the ZTX758STZ.

Q: What is the physical package compatibility between these parts?

A: Both the ZTX758STZ (E-Line-3) and KSP92BU (TO-92-3) utilize three-lead Through Hole configurations with compatible footprints. Standard TO-92 PCB layouts accommodate both devices without modification.

Q: Are there differences in DC current gain between these parts?

A: Yes. The ZTX758STZ specifies minimum DC current gain (hFE) of 40 at 200 mA collector current and 10 V collector-emitter voltage. The KSP92BU specifies minimum hFE of 25 at 30 mA collector current and 10 V collector-emitter voltage. Circuit designs dependent on specific gain characteristics require verification against the applicable datasheet.

Q: What is the maximum operating temperature for each part?

A: The ZTX758STZ operates from −55°C to +200°C junction temperature. The KSP92BU operates to +150°C junction temperature. Applications requiring operation above +150°C require the ZTX758STZ.

Q: Do both parts meet current environmental compliance standards?

A: Both parts are actively manufactured and carry current compliance designations. The ZTX758STZ is RoHS3 Compliant and REACH Unaffected. The KSP92BU maintains EAR99 export classification. Procurement specifications should confirm compliance status with current regulatory requirements at time of purchase.

Q: What inventory considerations apply to these parts?

A: The ZTX758STZ maintains 10,100 pieces in stock. The KSP92BU maintains 105,400 pieces in stock. Higher KSP92BU availability may support extended production runs or rapid fulfillment requirements where voltage and power derating is acceptable.