SG313 Inrush Current Limiter - Equivalent & Substitute Parts

Part Overview

The SG313 is an inrush current limiter manufactured by Ametherm, rated at 10 Ohms ±15% with a maximum steady-state current of 3 A. This component is part of the SURGE-GARD™ series and maintains active product status. Inrush current limiters are essential in power supply circuits to suppress transient currents during device startup, protecting downstream components from thermal and electrical stress. Alternative models may be required due to inventory constraints, specific packaging requirements, or application-specific mechanical dimensions.

Substiute Parts

SG313

AmethermIn Stock: 1037SG313 Datasheet

Current PartRFQ

B57235S0100M000

EPCOS - TDK ElectronicsIn Stock: 13837B57235S0100M000 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

The B57235S0100M000 (EPCOS - TDK Electronics) qualifies as a functional substitute for the SG313 based on the following critical parameters:

• Resistance value: Both parts are rated at 10 Ohms
• Current rating: Both support 3 A steady-state maximum current
• Tolerance: SG313 ±15% vs. B57235S0100M000 ±20% (wider tolerance acceptable for inrush limiting applications)
• RoHS compliance: Both are ROHS3 compliant
• Moisture sensitivity: Both rated MSL 1 (Unlimited)
• REACH status: Both unaffected

Mechanical differences exist in diameter (11.43mm vs. 9.50mm) and lead spacing (7.87mm vs. 5.00mm), which may require PCB layout verification depending on application constraints.

Parameter Comparison

Engineering Selection Recommendations

Both the SG313 and B57235S0100M000 meet core electrical requirements for 10 Ohm, 3 A inrush current limiting applications. The B57235S0100M000 offers broader regulatory approval coverage (CQC, UL, VDE) compared to the SG313 (CSA, UR), making it suitable for applications requiring expanded certification scope. The tolerance difference (±15% vs. ±20%) is within acceptable limits for inrush limiting circuits where precise resistance matching is not critical. Selection between these parts should be based on PCB layout constraints, as the B57235S0100M000 features a smaller physical footprint and reduced lead spacing.

Frequently Asked Questions (FAQ)

Q: Can the B57235S0100M000 directly replace the SG313 in existing designs?

A: Electrical substitution is valid based on matching resistance, current rating, and compliance standards. However, mechanical differences in diameter and lead spacing require PCB layout verification. Footprint modifications may be necessary.

Q: Does the ±20% tolerance of the B57235S0100M000 affect performance compared to the SG313's ±15% tolerance?

A: For inrush current limiting applications, the tolerance difference is functionally acceptable. Both parts operate within the resistance range required for transient suppression in typical power supply circuits.

Q: Are there regulatory or certification differences between these parts?

A: Yes. The SG313 carries CSA and UR approvals, while the B57235S0100M000 carries CQC, UL, and VDE approvals. Application requirements should determine which certification set is necessary.

Q: What are the mechanical constraints when substituting these parts?

A: The B57235S0100M000 is physically smaller (9.50mm diameter vs. 11.43mm) with tighter lead spacing (5.00mm vs. 7.87mm). Verify PCB pad spacing and component clearance before implementation.

Q: Are both parts RoHS compliant?

A: Yes, both the SG313 and B57235S0100M000 are ROHS3 compliant and REACH unaffected, meeting environmental regulatory requirements.