ST-202S Common Mode Choke Equivalent & Substitute Parts

Part Overview

The ST-202S is a 2-line common mode choke manufactured by KEMET, designed for through-hole applications requiring EMI filtering at 600 Ohms impedance @ 100 MHz. This component is rated for 1A maximum current with a DC resistance of 35mOhm and operates across a temperature range of -20°C to 75°C. The part maintains Active product status and is ROHS3 compliant, making it suitable for modern electronic assemblies requiring regulatory compliance.

Equivalent and substitute parts are identified when they maintain the same functional specifications across critical electrical and mechanical parameters, ensuring direct interchangeability in circuit designs without performance degradation.

Substiute Parts

ST-202S

KEMETIn Stock: 798ST-202S Datasheet

Current PartRFQ

ST-202

KEMETIn Stock: 951ST-202 Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the ST-202S is determined by strict equivalence across the following critical parameters:

• Electrical Performance: Impedance value (600 Ohms @ 100 MHz), current rating (1A), and DC resistance must remain within acceptable tolerances
• Electrical Ratings: Voltage rating (50V DC) and operating temperature range (-20°C ~ 75°C)
• Mechanical Compatibility: Mounting type (Through Hole), package configuration (Vertical, No Base, 4 PC Pin), and pin count
• Regulatory Compliance: ROHS3 compliance and REACH status

The ST-202 qualifies as a parametric equivalent based on matching electrical specifications (impedance, current rating, voltage, temperature range) and mechanical form factor. The variance in DC resistance (40mOhm vs. 35mOhm) and physical dimensions represents acceptable tolerance within the ST series design envelope.

Parameter Comparison

Engineering Selection Recommendations

Both the ST-202S and ST-202 maintain Active product status with ROHS3 compliance and REACH unaffected designation, confirming regulatory alignment for current manufacturing standards.

Selection between these parts is determined by:

• Primary Electrical Match: Both parts deliver identical impedance (600 Ohms @ 100 MHz), current capacity (1A), and voltage rating (50V DC), confirming functional equivalence in EMI filtering applications
• DC Resistance Tolerance: The ST-202 exhibits 40mOhm DCR versus 35mOhm for the ST-202S, representing a 5mOhm differential. This variance is within typical component tolerance and does not affect circuit performance in standard filtering applications
• Physical Footprint: The ST-202 occupies a larger form factor (0.630" diameter, 0.354" height) compared to the ST-202S (0.512" diameter, 0.276" height). PCB layout constraints may necessitate the more compact ST-202S in space-restricted designs
• Inventory Availability: Selection may be influenced by stock levels and procurement lead times

Frequently Asked Questions (FAQ)

Q: Can ST-202 replace ST-202S in existing designs? A: Yes. Both parts share identical electrical specifications for impedance, current rating, voltage, and operating temperature. The ST-202 is a direct functional equivalent. Physical dimensions differ; verify PCB layout accommodates the larger form factor (0.630" diameter vs. 0.512").

Q: What is the significance of the 5mOhm DCR difference? A: DC resistance variance between 35mOhm and 40mOhm represents normal component tolerance within the ST series. This differential does not impact EMI filtering performance or circuit operation in standard applications.

Q: Are both parts ROHS3 compliant? A: Yes. Both ST-202S and ST-202 are ROHS3 compliant and REACH unaffected, meeting current regulatory requirements for electronic component manufacturing.

Q: What determines substitution eligibility? A: Substitution is based on matching impedance value, current rating, voltage rating, operating temperature range, mounting type, and package configuration. Both parts satisfy these criteria.

Q: Does the physical size difference affect electrical performance? A: No. The dimensional variance reflects design iteration within the ST series but does not alter electrical characteristics. Selection is based on PCB layout requirements and available board space.