SC1704-3R3 Equivalent & Substitute Parts

Part Overview

The SC1704-3R3 is a 3.3 µH fixed unshielded inductor manufactured by Signal Transformer, rated for 1.25 A continuous current with a maximum DC resistance of 190mOhm. This component is classified as obsolete, making identification of suitable substitute parts essential for ongoing design support and procurement continuity. The part operates across the industrial temperature range of -40°C to 125°C and is ROHS3 compliant.

Substiute Parts

SC1704-3R3

Signal TransformerIn Stock: 1025SC1704-3R3 Datasheet

Current PartRFQ

SDR6603-3R3M

Bourns Inc.In Stock: 964SDR6603-3R3M Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SC1704-3R3 is determined by the following critical parameters:

• Inductance Value: Must be 3.3 µH with ±20% tolerance
• Current Rating: Substitute must support minimum 1.25 A continuous current
• DC Resistance: Lower DCR values are acceptable; higher values may impact circuit performance
• Shielding Configuration: Unshielded topology must be maintained
• Mounting Type: Surface mount configuration required
• Operating Temperature: Must support -40°C to 125°C range
• Compliance: ROHS3 compliance required

The SDR6603-3R3M meets all substitution criteria with improved electrical characteristics, including higher current rating (2 A) and lower DC resistance (80mOhm Max).

Parameter Comparison

Engineering Selection Recommendations

The SDR6603-3R3M is the qualified substitute for the obsolete SC1704-3R3. Selection is based on the following factors:

• Product Status: The main part is obsolete; the substitute is active and in production
• Electrical Compatibility: Both parts maintain identical inductance value and tolerance at the 100 kHz test frequency
• Current Margin: The substitute provides 60% higher current rating (2 A vs 1.25 A), ensuring adequate headroom for circuit operation
• Resistance Improvement: The substitute exhibits 58% lower DC resistance (80mOhm vs 190mOhm), reducing power dissipation
• Compliance Alignment: Both parts are ROHS3 compliant with identical moisture sensitivity ratings
• Temperature Range: Operating temperature specifications are identical across both parts
• Availability: The substitute is in active production with established supply chain availability

Frequently Asked Questions (FAQ)

Q: Can the SDR6603-3R3M directly replace the SC1704-3R3 in existing designs?

A: Yes. Both parts share identical inductance values, tolerance specifications, operating temperature ranges, and compliance certifications. The substitute provides improved electrical performance with higher current rating and lower DC resistance.

Q: What are the physical dimension differences between these parts?

A: The SC1704-3R3 measures 0.264" L x 0.220" W x 0.043" H (6.70mm x 5.60mm x 1.10mm). The SDR6603-3R3M measures 0.260" L x 0.175" W x 0.115" H (6.60mm x 4.45mm x 2.92mm). The substitute is slightly shorter in length and width but taller in height due to its drum core wirewound construction.

Q: Are there packaging differences to consider?

A: The main part uses nonstandard packaging, while the substitute is supplied in Tape & Reel (TR) format, which is standard for automated assembly processes.

Q: How do the DC resistance specifications affect circuit performance?

A: The substitute's 80mOhm maximum DC resistance is significantly lower than the main part's 190mOhm maximum. This reduces resistive losses and heat generation in the inductor, improving overall circuit efficiency.

Q: What is the saturation current difference between these parts?

A: The SC1704-3R3 saturates at 800mA, while the SDR6603-3R3M saturates at 2A. The substitute provides greater current handling capability before saturation occurs.

Q: Are both parts RoHS compliant?

A: Yes. Both the SC1704-3R3 and SDR6603-3R3M are ROHS3 compliant with MSL rating of 1 (Unlimited), indicating no moisture sensitivity restrictions.