KWS5-12 AC/DC Converter Equivalent & Substitute Parts

Part Overview

The KWS5-12 is a 5W enclosed AC/DC converter manufactured by TDK-Lambda Americas Inc, designed for commercial ITE applications. It provides a single 12V output at 450mA maximum current from universal AC input (85–265 VAC). The unit features through-hole mounting in a 5-DIP module package with dimensions of 54.9mm × 45.0mm × 20.5mm.

The KWS5-12 is classified as obsolete. Identifying equivalent and substitute parts is necessary to maintain design continuity, ensure supply chain availability, and support ongoing production or field replacement requirements for systems currently utilizing this converter.

Substiute Parts

KWS5-12

TDK-Lambda Americas IncIn Stock: 1197KWS5-12 Datasheet

Current PartRFQ

KPSA5-12

TDK-Lambda Americas IncIn Stock: 1272KPSA5-12 Datasheet

DirectRFQ

KWS5A-12

TDK-Lambda Americas IncIn Stock: 1887KWS5A-12 Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the KWS5-12 are identified based on the following critical parameters that determine functional and mechanical compatibility:

Primary Compatibility Criteria:

• Output voltage: 12V (exact match required)
• Power rating: 5W (exact match required)
• Input voltage range: 85–265 VAC minimum coverage (substitutes must support this range)
• Output current capacity: 450mA (substitutes must meet or exceed this value)
• Mounting type: Through hole (required for PCB integration)
• Number of outputs: Single output (required)
• Applications: ITE (Commercial) (same application class)

Secondary Considerations:

• Package/case type: DIP module format (physical form factor)
• Operating temperature range: Minimum −10°C to 70°C coverage
• Regulatory approvals: CE, CSA, UL (baseline compliance)

Two substitute parts meet these criteria: the KWS5A-12 and KPSA5-12, each with distinct characteristics affecting their suitability for different deployment scenarios.

Parameter Comparison

Engineering Selection Recommendations

KWS5A-12 Selection Criteria:

The KWS5A-12 is the primary substitute for the KWS5-12. Both units are enclosed converters with identical output specifications (12V, 450mA, 5W) and matching through-hole mounting. The KWS5A-12 is currently in active production status, ensuring long-term availability. It supports extended input voltage coverage (85–265 VAC and 120–370 VDC), providing additional flexibility for applications requiring DC input capability. The operating temperature range extends to 85°C, exceeding the original specification. The KWS5A-12 is RoHS compliant and REACH unaffected, meeting modern environmental standards. Physical dimensions are more compact (38.1 × 25.4 × 21.5mm versus 54.9 × 45.0 × 20.5mm), which may require PCB layout verification for space-constrained designs. CE approval is provided; however, CSA, TUV, and UL certifications are not listed for this model.

KPSA5-12 Selection Criteria:

The KPSA5-12 is a secondary substitute suitable for applications where open-frame construction is acceptable. This unit provides the same 12V output and 5W power rating with universal AC input (85–264 VAC). It maintains through-hole mounting compatibility and is actively produced. The KPSA5-12 carries CE, CSA, EN, and UL approvals, providing broader regulatory coverage than the KWS5A-12. However, the maximum output current is not specified in available documentation, requiring verification against the 450mA requirement. The open-frame design results in significantly lower weight (29.03g versus 75.3g) and smaller footprint (55.1 × 32.6 × 21.1mm), making it suitable for compact applications. Operating temperature range is limited to 0–70°C, matching the original specification's upper bound but with a higher minimum temperature. Efficiency is lower at 72% compared to the original 76%.

Recommendation Summary:

For direct replacement in existing designs with minimal modification, select the KWS5A-12. For applications requiring maximum regulatory compliance and compact form factor, select the KPSA5-12 after confirming output current specifications with the manufacturer.

Frequently Asked Questions (FAQ)

Q1: Can the KWS5A-12 be used as a direct drop-in replacement for the KWS5-12?

A: The KWS5A-12 provides identical electrical output specifications (12V, 450mA, 5W) and through-hole mounting. However, physical dimensions differ: the KWS5A-12 is more compact (38.1 × 25.4 × 21.5mm versus 54.9 × 45.0 × 20.5mm). PCB layout verification is required to confirm fit within the available space. The package changes from 5-DIP to 4-DIP, which may affect pin spacing and board routing.

Q2: What are the key differences between the KWS5A-12 and KPSA5-12?

A: The KWS5A-12 is an enclosed converter; the KPSA5-12 is open-frame. The KWS5A-12 supports both AC and DC input (85–265 VAC, 120–370 VDC); the KPSA5-12 supports AC input only (85–264 VAC). The KWS5A-12 operates to 85°C; the KPSA5-12 operates to 70°C. The KPSA5-12 is significantly lighter (29.03g versus unspecified weight for KWS5A-12). Regulatory approvals differ: KWS5A-12 has CE only; KPSA5-12 has CE, CSA, EN, and UL.

Q3: Is the KPSA5-12 suitable for applications requiring 450mA output current?

A: The maximum output current for the KPSA5-12 is not specified in the provided documentation. Confirmation from the manufacturer is required before selecting this part for applications with 450mA current demands.

Q4: What regulatory approvals should I prioritize when selecting a substitute?

A: The original KWS5-12 carries CE, CSA, TUV, and UL approvals. The KWS5A-12 provides CE approval only. The KPSA5-12 provides CE, CSA, EN, and UL approvals. Select based on the regulatory requirements of your target market and application.

Q5: Can the KPSA5-12 be used in applications requiring enclosed construction?

A: No. The KPSA5-12 is an open-frame design. Applications requiring environmental protection, EMI shielding, or enclosed construction must use the KWS5A-12 or source an alternative enclosed converter.

Q6: What is the impact of the extended operating temperature range of the KWS5A-12?

A: The KWS5A-12 operates from −10°C to 85°C with derating, compared to the KWS5-12's −10°C to 70°C range. This provides additional thermal margin for applications in elevated ambient conditions or with restricted cooling. Verify that the extended upper temperature limit does not conflict with component derating curves in your design.

Q7: Are both substitute parts RoHS compliant?

A: Yes. The KWS5A-12 is RoHS compliant and REACH unaffected. The KPSA5-12 is RoHS compliant and REACH unaffected. Both meet modern environmental standards.

Q8: How do efficiency ratings compare across the three models?

A: KWS5-12: 76% efficiency. KWS5A-12: 75% efficiency. KPSA5-12: 72% efficiency. The KWS5A-12 maintains efficiency within 1 percentage point of the original. The PKSA5-12 shows a 4 percentage point reduction, which may impact thermal design in power-limited applications.