SC1813FH-3R3 Equivalent & Substitute Parts

Part Overview

The SC1813FH-3R3 is a 3.3 µH unshielded wirewound inductor manufactured by Signal Transformer, designed for surface mount applications requiring 3.3 A current rating and 43mOhm maximum DC resistance. This component is classified as Active product status with full RoHS3 compliance and unlimited moisture sensitivity rating. Substitute parts are identified when equivalent electrical performance and mechanical compatibility can be maintained within the specified parameter tolerances for this inductance value and current class.

Substiute Parts

SC1813FH-3R3

Signal TransformerIn Stock: 900SC1813FH-3R3 Datasheet

Current PartRFQ

UP1B-3R3-R

Eaton - Electronics DivisionIn Stock: 2775UP1B-3R3-R Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the SC1813FH-3R3 are qualified based on the following criteria:

Electrical Parameters (Primary):

• Inductance value must be 3.3 µH within ±20% tolerance
• Current rating must be sufficient to handle circuit requirements (minimum 2.9 A acceptable for applications not requiring full 3.3 A)
• Saturation current (Isat) must be 3 A or higher to prevent core saturation
• DC resistance must not exceed 43mOhm to maintain thermal and efficiency characteristics
• Inductance measurement frequency must be 100 kHz

Mechanical Parameters (Secondary):

• Mounting type must be Surface Mount
• Physical dimensions must be 0.350" L x 0.240" W (8.89mm x 6.10mm)
• Maximum seated height must not exceed 0.197" (5.00mm)
• Package type must be Nonstandard with Tape & Reel packaging

Compliance Parameters:

• RoHS compliance status must be maintained (RoHS3 or equivalent)
• Moisture Sensitivity Level must be 1 (Unlimited)
• Operating temperature range must support -40°C minimum

Parameter Comparison

Engineering Selection Recommendations

The UP1B-3R3-R from Eaton - Electronics Division qualifies as a direct substitute for the SC1813FH-3R3 based on the following engineering criteria:

Electrical Compatibility: All primary electrical parameters align within acceptable tolerances. The 3.3 µH inductance value, ±20% tolerance, and 100 kHz test frequency are identical. DC resistance of 42.8mOhm is within specification and slightly lower than the 43mOhm maximum, providing marginal improvement in efficiency. Saturation current of 3 A matches exactly.

Mechanical Compatibility: Physical dimensions, mounting type, and package configuration are identical. Both components use Tape & Reel packaging suitable for automated assembly. Height and footprint constraints are fully compatible with existing PCB layouts designed for the SC1813FH-3R3.

Compliance and Regulatory Status: Both components maintain RoHS compliance and unlimited moisture sensitivity rating (MSL 1). The main part specifies ROHS3 compliance while the substitute indicates RoHS compliance; both satisfy regulatory requirements for lead-free and restricted substance standards.

Operational Constraints: The substitute part has a reduced current rating of 2.9 A compared to 3.3 A on the main part. Selection of UP1B-3R3-R is appropriate only for applications where continuous current does not exceed 2.9 A. The operating temperature range of the substitute (-40°C ~ 85°C) is narrower than the main part (-40°C ~ 125°C); applications requiring operation above 85°C must use the SC1813FH-3R3.

Product Availability: Both components maintain Active product status with established supply channels. The substitute offers higher inventory availability (2700 Pcs) compared to the main part (874 Pcs).

Frequently Asked Questions (FAQ)

Q: Can UP1B-3R3-R be used as a direct replacement for SC1813FH-3R3 in all applications?

A: No. The substitute is suitable only for applications where continuous current does not exceed 2.9 A and operating temperature remains below 85°C. The main part supports 3.3 A continuous current and -40°C ~ 125°C operating range. Verify circuit current requirements before substitution.

Q: What is the difference between the core materials?

A: The SC1813FH-3R3 core material is not specified in the datasheet. The UP1B-3R3-R uses a ferrite drum core construction. Both are wirewound inductors with identical electrical specifications at 100 kHz test frequency. Core material differences do not affect substitution eligibility when electrical parameters match.

Q: Are the physical dimensions truly identical?

A: Yes. Both components have identical footprint dimensions of 0.350" L x 0.240" W (8.89mm x 6.10mm) and maximum seated height of 0.197" (5.00mm). PCB layout compatibility is guaranteed.

Q: What does the ±20% inductance tolerance mean for substitution?

A: Both parts are specified with ±20% tolerance, meaning actual inductance values can range from 2.64 µH to 3.96 µH. This tolerance applies to both the main part and substitute. Circuit designs must account for this tolerance range; substitution does not introduce additional tolerance variation.

Q: Why is the DC resistance specification important?

A: DC resistance directly affects power dissipation and thermal performance. The main part specifies 43mOhm maximum while the substitute is 42.8mOhm maximum. Lower DC resistance reduces I²R losses and heat generation. The substitute's slightly lower resistance is advantageous.

Q: Can I use UP1B-3R3-R in a high-temperature application requiring 100°C operation?

A: No. The UP1B-3R3-R operating temperature range is -40°C ~ 85°C, which does not support 100°C operation. The SC1813FH-3R3 with -40°C ~ 125°C range is required for this application.

Q: What is the significance of MSL 1 (Unlimited) rating?

A: MSL 1 indicates unlimited shelf life without moisture baking requirements. Both components can be stored and handled without time-sensitive moisture precautions, simplifying inventory management and assembly logistics.

Q: Are both components RoHS compliant?

A: Yes. The SC1813FH-3R3 is ROHS3 compliant and the UP1B-3R3-R is RoHS compliant. Both meet lead-free and restricted substance requirements. ROHS3 represents a more recent compliance standard; both satisfy current regulatory requirements.

Q: What packaging format is used for both parts?

A: Both components are supplied in Tape & Reel (TR) format, standard for automated surface mount assembly. Reel specifications and tape pitch are compatible with industry-standard pick-and-place equipment.

Q: How do I determine if my circuit can tolerate the 2.9 A current rating of the substitute?

A: Review your circuit schematic and calculate maximum continuous current through the inductor under worst-case operating conditions. If maximum current is ≤2.9 A, the substitute is acceptable. If maximum current exceeds 2.9 A, use the SC1813FH-3R3 to prevent saturation and component damage.