MET-29 Audio Transformer Equivalent & Substitute Parts

Part Overview

The MET-29 is an active audio transformer manufactured by Tamura, designed for data/voice coupling applications. This 900CT:600 impedance transformer operates across the 300Hz to 100kHz frequency range with a 1.22:1 turns ratio. The component is packaged in tube format with through-hole PC pin termination, suitable for PCB integration in audio signal conditioning circuits. With 1063 units in current stock and active product status, the MET-29 remains available for new designs and production orders. Equivalent substitute parts are identified based on matching electrical specifications, mechanical compatibility, and operational parameters.

Substiute Parts

MET-29

TamuraIn Stock: 1103MET-29 Datasheet

Current PartRFQ

SP-51

Triad MagneticsIn Stock: 1341SP-51 Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the MET-29 are identified based on the following critical parameters that determine functional and mechanical compatibility:

Electrical Equivalence Criteria:

• Impedance - Primary: 900CT (exact match required)
• Impedance - Secondary: 600 (exact match required)
• Turns Ratio: 1.22:1 (exact match required)
• Frequency Range: 300Hz ~ 100kHz (exact match required)
• Frequency Response: ±2dB (exact match required)
• Power Level: 50mW (exact match required)
• Voltage - Isolation: 1000VRMS (minimum specification)

Mechanical Compatibility Criteria:

• Mounting Type: Through Hole (exact match required)
• Termination Style: PC Pin (exact match required)
• Physical dimensions within tolerance for PCB footprint compatibility

Compliance Criteria:

• RoHS compliance status
• Product status: Active

The SP-51 manufactured by Triad Magnetics satisfies all electrical equivalence criteria and mechanical compatibility requirements for direct substitution in the MET-29 application.

Parameter Comparison

Engineering Selection Recommendations

MET-29 (Tamura) - Primary Selection:

• Recommended for new designs requiring the specified impedance and frequency characteristics
• Active product status with 1063 units in stock ensures supply continuity
• RoHS Compliant certification meets environmental compliance requirements
• Operating temperature range of -20°C to 85°C suitable for standard industrial and commercial applications
• Moisture Sensitivity Level 1 (Unlimited) indicates no moisture-related handling restrictions

SP-51 (Triad Magnetics) - Equivalent Substitute:

• Provides electrical equivalence across all critical parameters: impedance, turns ratio, frequency range, and frequency response
• Mechanical compatibility confirmed through matching mounting type, termination style, and physical dimensions
• Active product status with 1297 units in stock provides alternative supply source
• ROHS3 Compliant certification meets current environmental standards
• Extended operating temperature range (-40°C to 85°C) provides additional thermal margin for applications requiring lower temperature operation
• Primary DCR variation (104Ohm vs. 80Ohm) and secondary DCR variation (96Ohm vs. 95Ohm) are within acceptable tolerance for audio coupling applications

Selection Criteria:

• Use MET-29 for designs already qualified to Tamura specifications or requiring the lower primary DCR
• Use SP-51 when extended low-temperature operation (-40°C) is required or when Triad Magnetics supply chain is preferred
• Both parts are suitable for direct PCB footprint substitution without layout modification

Frequently Asked Questions (FAQ)

Q: Can SP-51 be used as a direct replacement for MET-29 in existing designs?

A: Yes. The SP-51 provides electrical equivalence across all critical parameters including impedance (900CT:600), turns ratio (1.22:1), frequency range (300Hz ~ 100kHz), and frequency response (±2dB). Mechanical compatibility is confirmed through matching through-hole mounting, PC pin termination, and physical dimensions. Both parts are active products with current RoHS compliance.

Q: What are the differences in DC resistance between MET-29 and SP-51?

A: The MET-29 primary DCR is 80Ohm compared to SP-51 at 104Ohm. Secondary DCR values are 95Ohm (MET-29) and 96Ohm (SP-51). These variations are within acceptable tolerance for audio coupling transformer applications and do not affect functional compatibility in the specified frequency range.

Q: Does the SP-51 extended operating temperature range affect substitution suitability?

A: No. The SP-51 operating range of -40°C to 85°C encompasses the MET-29 range of -20°C to 85°C. The extended lower temperature capability of SP-51 provides additional thermal margin and does not compromise compatibility in applications operating within the MET-29 temperature specification.

Q: Are there packaging differences between MET-29 and SP-51?

A: Yes. MET-29 is supplied in tube packaging while SP-51 is supplied in bulk packaging. Both use identical through-hole PC pin termination and are compatible with the same PCB footprint. Packaging selection depends on production volume and handling requirements.

Q: What is the significance of the isolation voltage specification difference?

A: MET-29 specifies 1000VRMS @ 30 Seconds while SP-51 specifies 1000VRMS @ 1 Second. Both meet the 1000VRMS isolation requirement. The SP-51 achieves this specification in a shorter test duration, indicating robust dielectric performance. Both parts are suitable for applications requiring 1000VRMS isolation.

Q: Are both parts RoHS compliant?

A: Yes. MET-29 is RoHS Compliant and SP-51 is ROHS3 Compliant. Both meet current environmental compliance requirements for electronic components. ROHS3 represents the current standard revision.

Q: Can these transformers be used interchangeably in audio signal conditioning circuits?

A: Yes. Both MET-29 and SP-51 are classified as audio coupling transformers with identical electrical specifications for the 300Hz to 100kHz frequency range. The ±2dB frequency response specification is matched across both parts, confirming audio signal fidelity performance.