2SD21340RA Equivalent & Substitute Parts

Part Overview

The 2SD21340RA is an NPN bipolar junction transistor manufactured by Panasonic Electronic Components, designed for general-purpose switching and amplification applications. This device features a maximum collector current of 1 A, collector-emitter breakdown voltage of 150 V, and maximum power dissipation of 1.5 W in a Through Hole MT-3-A1 package.

The 2SD21340RA is classified as obsolete. Locating equivalent substitute parts is necessary to support ongoing maintenance, repair, and new design requirements where this component is specified or functionally required.

Substiute Parts

2SD21340RA

Panasonic Electronic ComponentsIn Stock: 11922SD21340RA Datasheet

Current PartRFQ

KSC2690AYS

onsemiIn Stock: 1374KSC2690AYS Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 2SD21340RA is determined by electrical and mechanical compatibility across the following critical parameters:

Electrical Compatibility Criteria:

• Transistor Type: NPN configuration required
• Current - Collector (Ic) (Max): Substitute must equal or exceed 1 A
• Voltage - Collector Emitter Breakdown (Max): Substitute must equal or exceed 150 V
• Power - Max: Substitute must equal or exceed 1.5 W
• Frequency - Transition: Substitute must equal or exceed 200 MHz
• Operating Temperature: Substitute must support 150°C (TJ) or higher

Mechanical Compatibility Criteria:

• Mounting Type: Through Hole required
• Package / Case: Physical footprint compatibility with MT-3-A1 or equivalent 3-pin through-hole packages

The KSC2690AYS meets these substitution criteria with electrical ratings that equal or exceed the 2SD21340RA specifications, enabling functional replacement in circuit applications.

Parameter Comparison

Engineering Selection Recommendations

KSC2690AYS as Primary Substitute:

The KSC2690AYS is an active product manufactured by onsemi and qualifies as a functional equivalent to the obsolete 2SD21340RA. The substitute part exceeds the collector current specification (1.2 A vs. 1 A) and collector-emitter breakdown voltage (160 V vs. 150 V), providing operational margin in these critical parameters. Both devices support identical maximum operating junction temperature (150°C).

The KSC2690AYS is ROHS3 compliant and REACH unaffected, offering improved environmental and regulatory compliance compared to the non-compliant 2SD21340RA. Active product status ensures ongoing availability and supply chain continuity.

Package Consideration:

The KSC2690AYS uses a TO-126-3 package, which differs from the MT-3-A1 package of the original part. Both are three-pin through-hole packages with compatible pin configurations for NPN transistor applications. Physical board layout verification is required to confirm mechanical fit within existing PCB designs.

Transition Frequency Trade-off:

The KSC2690AYS transition frequency (155 MHz) is lower than the 2SD21340RA (200 MHz). This parameter difference is acceptable for general-purpose switching applications but requires evaluation in high-frequency or timing-critical circuits.

Frequently Asked Questions (FAQ)

Q: Can the KSC2690AYS directly replace the 2SD21340RA in all applications?

A: The KSC2690AYS meets or exceeds all critical electrical parameters (collector current, breakdown voltage, operating temperature) required for functional substitution. However, the lower transition frequency (155 MHz vs. 200 MHz) may impact performance in high-frequency applications. Circuit-level evaluation is necessary for frequency-dependent designs.

Q: What is the primary difference between these two transistors?

A: The 2SD21340RA is an obsolete Panasonic part in MT-3-A1 packaging, while the KSC2690AYS is an active onsemi product in TO-126-3 packaging. The KSC2690AYS provides higher collector current capability (1.2 A vs. 1 A) and improved regulatory compliance (ROHS3 compliant vs. non-compliant).

Q: Are the packages physically compatible?

A: Both the MT-3-A1 and TO-126-3 packages are three-pin through-hole configurations suitable for NPN transistor applications. Physical compatibility depends on specific PCB layout and mounting hole spacing. Mechanical verification against board design is required before implementation.

Q: What is the significance of the product status difference?

A: The 2SD21340RA is obsolete, indicating discontinued manufacturing and limited future availability. The KSC2690AYS is active, ensuring ongoing supply, technical support, and compliance with current industry standards. Active status is advantageous for long-term design support and production continuity.

Q: Does the KSC2690AYS meet environmental compliance requirements?

A: Yes. The KSC2690AYS is ROHS3 compliant and REACH unaffected, meeting current environmental and regulatory requirements. The 2SD21340RA is RoHS non-compliant, which may restrict use in regulated applications or regions with strict environmental standards.

Q: How should the transition frequency difference be evaluated?

A: The transition frequency (fT) determines the maximum useful operating frequency for the transistor. The KSC2690AYS at 155 MHz is suitable for general-purpose switching and audio-frequency amplification. Applications requiring operation above 155 MHz require detailed frequency response analysis to confirm acceptable performance margins.