KSE340STSTU Equivalent & Substitute Parts

Part Overview

The KSE340STSTU is an NPN bipolar junction transistor manufactured by onsemi, rated for 300 V collector-emitter breakdown voltage and 500 mA maximum collector current in a TO-126-3 through-hole package. This device is classified as obsolete, indicating discontinued production and limited availability. Identifying equivalent substitute parts is necessary to maintain design continuity and ensure component procurement for new production runs or field replacements where the original part is no longer readily available through standard distribution channels.

Substiute Parts

KSE340STSTU

onsemiIn Stock: 817KSE340STSTU Datasheet

Current PartRFQ

MJE340G

onsemiIn Stock: 6945MJE340G Datasheet

DirectRFQ

MJE340

NTE Electronics, IncIn Stock: 2035MJE340 Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the KSE340STSTU are selected based on electrical parameter equivalence and mechanical compatibility. The critical parameters determining substitution validity are:

• Transistor Type: NPN configuration
• Collector Current Rating: 500 mA maximum
• Collector-Emitter Breakdown Voltage: 300 V
• DC Current Gain (hFE): 30 @ 50mA, 10V minimum
• Maximum Power Dissipation: 20 W
• Mounting Type: Through Hole
• Package Compatibility: TO-126-3 or equivalent TO-126 footprint

The substitute parts MJE340G and MJE340 meet all electrical specifications and package requirements. Both devices maintain identical voltage, current, and gain ratings, ensuring functional equivalence in circuit applications. Package variations (TO-126 vs. TO-126-3) are mechanically compatible for through-hole mounting applications.

Parameter Comparison

Engineering Selection Recommendations

MJE340G (onsemi) is the primary recommended substitute for the obsolete KSE340STSTU. This part maintains identical electrical specifications across all critical parameters and is manufactured by the same original equipment manufacturer. The MJE340G is classified as active product status with ROHS3 compliance, ensuring long-term availability and regulatory alignment with modern manufacturing standards. The extended operating temperature range (-65°C ~ 150°C) provides additional thermal margin compared to the original part specification.

MJE340 (NTE Electronics, Inc) serves as a secondary substitute option. This part meets all electrical requirements and maintains mechanical compatibility through the TO-126 package. However, the MJE340 is classified as RoHS non-compliant and lacks specified operating temperature range data. This part is suitable for applications where RoHS compliance is not a requirement and where the original operating temperature specification is sufficient.

Both substitute parts are actively stocked and available in quantities exceeding the original part inventory, providing reliable procurement alternatives for the discontinued KSE340STSTU.

Frequently Asked Questions (FAQ)

Q: Can MJE340G directly replace KSE340STSTU in existing circuit designs?

A: Yes. The MJE340G maintains identical electrical specifications for collector current (500 mA), collector-emitter breakdown voltage (300 V), DC current gain (30 @ 50mA, 10V), and maximum power dissipation (20 W). The TO-126 package is mechanically compatible with TO-126-3 footprints in through-hole applications.

Q: What is the difference between MJE340G and MJE340?

A: Both parts meet identical electrical specifications. The primary differences are manufacturer (onsemi vs. NTE Electronics, Inc), RoHS compliance status (ROHS3 Compliant vs. RoHS Non-Compliant), and specified operating temperature range (MJE340G specifies -65°C ~ 150°C; MJE340 does not specify). Select based on compliance requirements and temperature operating conditions.

Q: Are TO-126 and TO-126-3 packages interchangeable?

A: Yes, for through-hole mounting applications. Both packages use identical lead spacing and hole patterns, allowing direct substitution on printed circuit boards designed for either package variant.

Q: Why is the KSE340STSTU classified as obsolete?

A: Obsolete status indicates the manufacturer has discontinued production. The MJE340 series represents the active product line replacement, offering equivalent performance with modern manufacturing and compliance standards.

Q: Which substitute part should be selected for new designs?

A: MJE340G is recommended for new designs. This part is actively manufactured by onsemi, maintains ROHS3 compliance, and provides extended operating temperature specifications suitable for modern applications.

Q: Is there a difference in collector cutoff current between the substitute parts?

A: MJE340G specifies 100 µA (ICBO) maximum, matching the original KSE340STSTU specification. MJE340 does not provide collector cutoff current specification. For applications sensitive to leakage current, MJE340G is the preferred selection.