SCR105B-820 Equivalent & Substitute Parts

Part Overview

The SCR105B-820 is a 82 µH shielded inductor manufactured by Signal Transformer, rated for 1.57 A continuous current with a maximum DC resistance of 280mOhm. This component is classified as obsolete, making identification of functionally equivalent alternatives 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

SCR105B-820

Signal TransformerIn Stock: 1227SCR105B-820 Datasheet

Current PartRFQ

7447714820

Würth ElektronikIn Stock: 23377447714820 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SCR105B-820 is determined by the following critical parameters:

• Inductance Value: 82 µH with ±20% tolerance
• Current Rating: Minimum 1.57 A continuous current capability
• DC Resistance: Maximum 280 mOhm to maintain circuit performance
• Shielding: Shielded construction required
• Temperature Range: -40°C to 125°C operating window
• Mounting: Surface mount configuration
• Compliance: RoHS3 compliance maintained

The substitute part 7447714820 (Würth Elektronik WE-PD Performance series) meets all critical electrical and mechanical parameters within acceptable tolerances for direct substitution.

Parameter Comparison

Engineering Selection Recommendations

The 7447714820 (Würth Elektronik WE-PD Performance series) is a direct functional equivalent for the obsolete SCR105B-820. Selection criteria are based on the following factors:

Product Status: The substitute part carries Active product status, ensuring long-term availability and supply chain continuity compared to the obsolete main part.

Electrical Performance: The substitute meets or exceeds all critical electrical parameters. The 1.6 A current rating provides 1.9% margin above the 1.57 A requirement. The 176 mOhm maximum DC resistance is 37% lower than the 280 mOhm specification, resulting in reduced power dissipation and improved thermal performance.

Compliance & Certifications: Both parts maintain RoHS3 compliance and identical operating temperature ranges (-40°C to 125°C). The substitute carries AEC-Q200 automotive qualification, providing additional reliability assurance.

Physical Compatibility: Both components use nonstandard surface mount packages with comparable footprints (10.00mm x 10.00mm vs. 10.50mm x 9.50mm) and heights (5.00mm vs. 5.50mm), allowing direct PCB layout substitution with minimal design modification.

Frequently Asked Questions (FAQ)

Q: Can the 7447714820 be used as a direct replacement for the SCR105B-820?

A: Yes. The 7447714820 meets all critical electrical and mechanical parameters required for substitution, including inductance value, current rating, DC resistance, shielding, temperature range, and mounting type. Physical dimensions are comparable and compatible with existing PCB layouts.

Q: What are the key differences between these parts?

A: The primary differences are product status (obsolete vs. active), DC resistance (280 mOhm vs. 176 mOhm), saturation current (790 mA vs. 1.9 A), and core construction (unspecified vs. ferrite drum core wirewound). The substitute offers superior electrical performance with lower losses and higher saturation margins.

Q: Are there any thermal or power dissipation advantages to using the substitute?

A: Yes. The 176 mOhm maximum DC resistance of the 7447714820 is significantly lower than the 280 mOhm specification of the SCR105B-820. At the rated 1.57 A current, this results in approximately 37% lower resistive power dissipation, improving thermal performance and component reliability.

Q: What is the packaging difference between these parts?

A: Both parts use nonstandard surface mount packages. The SCR105B-820 measures 10.50mm x 9.50mm x 5.50mm (L x W x H), while the 7447714820 measures 10.00mm x 10.00mm x 5.00mm. These dimensions are sufficiently similar to allow direct PCB substitution without layout redesign.

Q: Does the substitute part have any additional certifications?

A: Yes. The 7447714820 carries AEC-Q200 automotive qualification, indicating compliance with automotive reliability and quality standards. Both parts maintain RoHS3 compliance and unlimited moisture sensitivity level (MSL 1).

Q: What is the inductance test frequency for each part?

A: The SCR105B-820 is tested at 2.52 kHz, while the 7447714820 is tested at 100 kHz. Both parts maintain the specified 82 µH inductance value within ±20% tolerance across their respective test frequencies.