DST-2-20 Equivalent & Substitute Parts

Part Overview

The DST-2-20 is a laminated core power transformer manufactured by Signal Transformer, rated at 1.1VA with dual primary and secondary windings. The device supports dual input voltages (115V, 230V) and dual output configurations (parallel 10V at 110mA, series 20V at 55mA). This through-hole mounted transformer is designed for applications requiring isolated AC power conversion with 2500Vrms isolation capability. As an active product with ROHS3 compliance, the DST-2-20 remains in production; however, equivalent alternatives may be required for supply chain optimization, inventory management, or specific application constraints.

Substiute Parts

DST-2-20

Signal TransformerIn Stock: 849DST-2-20 Datasheet

Current PartRFQ

FS20-055

Triad MagneticsIn Stock: 945FS20-055 Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the DST-2-20 is determined by strict equivalence across the following critical parameters:

• Power rating: 1.1VA
• Primary voltage configuration: Dual 115V/230V
• Secondary voltage configuration: Parallel 10V/Series 20V
• Output current capacity: Parallel 110mA/Series 55mA
• Winding configuration: Dual primary, dual secondary
• Isolation voltage: 2500Vrms minimum
• Mounting and termination: Through-hole with PC pin termination
• Core type: Laminated construction
• Regulatory compliance: ROHS3 compliance required

The FS20-055 manufactured by Triad Magnetics meets all specified electrical and mechanical parameters, making it a direct functional equivalent for the DST-2-20.

Parameter Comparison

Engineering Selection Recommendations

Both the DST-2-20 and FS20-055 are active products with identical electrical specifications and ROHS3 compliance certification. Selection between these parts should be based on:

• Availability and lead time requirements
• PCB layout constraints, noting the minimal height difference (24.60mm vs. 23.80mm seated height)
• Supplier inventory and pricing
• Established qualification history within the application circuit

The FS20-055 represents a functionally equivalent alternative with no electrical performance trade-offs relative to the DST-2-20.

Frequently Asked Questions (FAQ)

Q: Can the FS20-055 be used as a direct replacement for the DST-2-20 in existing designs?

A: Yes. The FS20-055 meets all electrical and mechanical specifications of the DST-2-20, including power rating, voltage configuration, current capacity, isolation voltage, and mounting characteristics. Physical dimensions are within acceptable tolerance for standard through-hole PCB layouts.

Q: Are there any compliance differences between these parts?

A: No. Both parts carry ROHS3 compliance certification and identical REACH and ECCN classifications (EAR99).

Q: What is the significance of the height difference between these transformers?

A: The FS20-055 seated height is 0.80mm lower than the DST-2-20 (23.80mm vs. 24.60mm). This difference is negligible for most applications but should be verified if the design includes height-constrained enclosures or stacked component arrangements.

Q: Are the physical dimensions identical?

A: Dimensions are equivalent within manufacturing tolerance. Length differs by 0.03mm (34.90mm vs. 34.93mm) and width by 0.04mm (28.60mm vs. 28.56mm), which is within standard PCB footprint acceptance criteria.

Q: What winding configurations do these transformers support?

A: Both transformers feature dual primary windings (115V/230V selectable) and dual secondary windings, enabling parallel output (10V at 110mA) or series output (20V at 55mA) configuration.