DST3-12B5 Equivalent & Substitute Parts

Part Overview

The DST3-12B5 is a laminated core power transformer manufactured by Pulse Electronics, rated at 2.4VA with dual primary and secondary windings. This through-hole mounted component is designed for applications requiring 115V or 230V primary input with configurable secondary output of 6.3V (parallel) or 12.6V (series). The product is active and RoHS compliant, with 1029 units currently in stock.

Equivalent and substitute parts are identified when component availability is limited, supply chain disruptions occur, or design flexibility permits alternative manufacturers meeting identical electrical and mechanical specifications.

Substiute Parts

DST3-12B5

Pulse ElectronicsIn Stock: 1111DST3-12B5 Datasheet

Current PartRFQ

DST-3-12

Signal TransformerIn Stock: 1213DST-3-12 Datasheet

DirectRFQ

3FD-312

TamuraIn Stock: 33393FD-312 Datasheet

SimilarRFQ

FS12-200-C2

Triad MagneticsIn Stock: 8322FS12-200-C2 Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the DST3-12B5 are classified based on electrical and mechanical compatibility within the following criteria:

Electrical Parameters (Must Match):

• Power rating: 2.4VA
• Primary voltage: 115V, 230V
• Secondary voltage configuration: Parallel 6.3V, Series 12.6V
• Output current: Parallel 400mA, Series 200mA
• Winding configuration: Dual primary, dual secondary
• Core type: Laminated
• Isolation voltage: 2500Vrms minimum

Mechanical Parameters (Must Match):

• Mounting type: Through Hole
• Termination style: PC Pin
• Physical dimensions: Within tolerance of 35.05mm L × 28.70mm W × 30.23mm H (seated)

Compliance Parameters:

• RoHS compliance required
• REACH unaffected status

All identified substitutes meet these criteria and are classified as direct equivalents or similar alternatives based on dimensional and compliance alignment.

Parameter Comparison

Engineering Selection Recommendations

All four parts listed are active products with current manufacturing status and full RoHS compliance. Selection among these equivalents is based on the following factors:

DST-3-12 (Signal Transformer): Direct equivalent with identical electrical specifications and comparable dimensions. ROHS3 compliance exceeds baseline RoHS requirements. Inventory of 1184 units supports consistent availability.

3FD-312 (Tamura): Meets all electrical requirements with slightly larger physical dimensions (width +2.30mm, height +1.87mm). Highest inventory level at 3266 units. Suitable for applications with dimensional tolerance for increased height and width.

FS12-200-C2 (Triad Magnetics): Meets all electrical requirements with enhanced isolation voltage rating of 4200Vrms, exceeding the 2500Vrms specification. Dimensions closely match the original part. Highest inventory availability at 8247 units. Suitable for applications requiring higher isolation margin.

All parts share identical electrical performance, winding configuration, and core type. Selection should prioritize application-specific dimensional constraints and isolation voltage requirements.

Frequently Asked Questions (FAQ)

Q: Can DST-3-12 replace DST3-12B5 directly? A: Yes. The DST-3-12 is electrically and mechanically equivalent with identical power rating, voltage configuration, current output, and winding arrangement. Dimensions vary by less than 1mm in length and width, and height by 0.57mm. Both are RoHS compliant and through-hole mounted with PC pin termination.

Q: What is the difference between 3FD-312 and the original DST3-12B5? A: The 3FD-312 provides identical electrical performance but has larger physical dimensions: width is 2.30mm greater and height is 1.87mm greater. This may affect PCB layout compatibility. Isolation voltage remains at 2500Vrms. Select this part only if board space permits the increased footprint.

Q: Why does FS12-200-C2 have higher isolation voltage? A: The FS12-200-C2 is rated at 4200Vrms isolation voltage compared to the 2500Vrms specification of DST3-12B5. This higher rating provides additional safety margin in high-voltage isolation applications. All other electrical and mechanical parameters are equivalent. This part is suitable for designs requiring enhanced isolation performance.

Q: Are all substitutes packaged identically? A: No. DST3-12B5 is packaged in boxes, while 3FD-312 and FS12-200-C2 are supplied in tubes. DST-3-12 is also box packaged. Packaging does not affect component functionality but may influence handling and storage procedures.

Q: Which substitute has the best inventory availability? A: FS12-200-C2 has the highest inventory at 8247 units, followed by 3FD-312 at 3266 units. Both provide strong supply chain security compared to the original DST3-12B5 at 1029 units.

Q: Can I use these parts interchangeably on the same PCB? A: Yes, provided your PCB layout accommodates the dimensional variations. DST-3-12 and FS12-200-C2 have nearly identical dimensions to the original. The 3FD-312 requires verification of clearance for its larger width and height. All parts use identical through-hole PC pin termination.