PF2205-12RF1 Equivalent & Substitute Parts

Part Overview

The PF2205-12RF1 is a 12 Ohms ±1% 50W through-hole resistor in TO-220-2 package manufactured by Riedon. This thin film current sense resistor is designed for high-power applications requiring precision and pulse withstanding capability. The part is classified as "Not For New Designs," making identification of suitable equivalent components essential for ongoing production support and design updates.

Substiute Parts

PF2205-12RF1

RiedonIn Stock: 690PF2205-12RF1 Datasheet

Current PartRFQ

PWR221T-50-12R0F

Bourns Inc.In Stock: 732PWR221T-50-12R0F Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the PF2205-12RF1 is determined by the following critical parameters:

• Resistance Value & Tolerance: 12 Ohms ±1% (exact match required)
• Power Rating: 50W (minimum requirement for thermal performance)
• Package Type: TO-220-2 (mechanical and thermal interface compatibility)
• Electrical Characteristics: Current sense capability, pulse withstanding performance
• Compliance: ROHS3 and REACH status for regulatory alignment

The PWR221T-50-12R0F from Bourns Inc. meets these core substitution criteria. While composition differs (thick film vs. thin film) and temperature coefficient varies (±100ppm/°C vs. ±50ppm/°C), the electrical performance parameters and package compatibility allow functional equivalence in applications where the specified tolerances are acceptable.

Parameter Comparison

Engineering Selection Recommendations

The PWR221T-50-12R0F is the primary equivalent for the PF2205-12RF1 based on matching electrical specifications and package compatibility. Both components are ROHS3 compliant and rated for 50W at 12 Ohms ±1%.

For applications currently using the PF2205-12RF1, transition to the PWR221T-50-12R0F is supported by:

• Active product status of the Bourns component, ensuring long-term availability
• Identical resistance, tolerance, and power rating
• Compatible TO-220-2 package footprint
• Equivalent current sense and pulse withstanding performance
• Full regulatory compliance alignment

Differences in temperature coefficient (±100ppm/°C vs. ±50ppm/°C) and maximum operating temperature (150°C vs. 155°C) should be evaluated against specific application requirements. The Bourns component operates within a slightly narrower temperature range and exhibits greater temperature-dependent resistance variation.

Frequently Asked Questions (FAQ)

Q: Can the PWR221T-50-12R0F directly replace the PF2205-12RF1 in existing designs?

A: Yes, for applications where the operating temperature does not exceed 150°C and the temperature coefficient specification of ±100ppm/°C is acceptable. Both components share identical resistance, tolerance, power rating, and TO-220-2 package configuration.

Q: What is the difference between thin film and thick film composition?

A: Thin film resistors (PF2205-12RF1) typically offer tighter tolerance and lower temperature coefficient. Thick film resistors (PWR221T-50-12R0F) provide robust pulse withstanding and current handling. For this 50W application, both compositions deliver equivalent performance in current sense circuits.

Q: Are there mechanical differences between the two parts?

A: Both use TO-220-2 packages. The PWR221T-50-12R0F is specified as "Full Pack," indicating a complete lead frame assembly. Physical dimensions vary slightly: PF2205-12RF1 is 0.417" L × 0.177" W with 0.591" seated height; PWR221T-50-12R0F is 0.410" L × 0.125" W with 0.760" seated height. PCB footprint compatibility should be verified for height-constrained applications.

Q: What compliance certifications apply to both parts?

A: Both components are ROHS3 compliant. The PF2205-12RF1 is REACH Affected; the PWR221T-50-12R0F is REACH Unaffected. Both carry EAR99 ECCN classification and HTSUS code 8533.29.0000.

Q: Why is the PF2205-12RF1 marked "Not For New Designs"?

A: This status indicates the component is in mature or end-of-life phase. The PWR221T-50-12R0F, with Active status, is the recommended choice for new designs and ongoing production requiring a 12 Ohm 50W TO-220 current sense resistor.