Bourns 7121-RC Common Mode Choke Equivalent & Substitute Parts

Part Overview

The Bourns 7121-RC is a through-hole common mode choke (CMC) designed for two-line filtering applications. This component provides 42.5 mH inductance at 1 kHz with a maximum current rating of 2A and 200 mOhm DC resistance. The part is currently active in production and ROHS3 compliant, making it suitable for modern electronic applications requiring EMI suppression in power and signal lines.

Substitute parts are identified when equivalent electrical performance can be achieved within the allowed parameter tolerances for this product category, or when design requirements permit operation at different inductance values while maintaining core electrical and mechanical compatibility.

Substiute Parts

7121-RC

Bourns Inc.In Stock: 7887121-RC Datasheet

Current PartRFQ

7116-RC

Bourns Inc.In Stock: 13627116-RC Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the Bourns 7121-RC is determined by the following criteria:

Mandatory Matching Parameters:

• Number of Lines: 2
• Current Rating (Max): 2A
• DC Resistance (DCR) (Max): 200 mOhm
• Mounting Type: Through Hole
• Package / Case: Vertical, No Base, 4 PC Pin
• Operating Temperature Range: -55°C ~ 105°C
• Series: 7100
• RoHS Status: ROHS3 Compliant

Variable Parameter:

• Inductance @ Frequency: May differ based on application requirements

The Bourns 7116-RC qualifies as a parametric equivalent within the 7100 series. While the inductance value differs (6.8 mH @ 1 kHz versus 42.5 mH @ 1 kHz), all other electrical and mechanical parameters remain identical, allowing substitution in applications where the lower inductance value is acceptable.

Parameter Comparison

Engineering Selection Recommendations

Both the Bourns 7121-RC and 7116-RC are active production parts with ROHS3 compliance and identical regulatory status (REACH Unaffected, ECCN EAR99). Selection between these parts depends on the specific inductance requirement of the application circuit.

The 7121-RC provides higher inductance (42.5 mH) and larger physical dimensions, suitable for applications requiring greater EMI attenuation. The 7116-RC offers lower inductance (6.8 mH) in a more compact form factor, appropriate for circuits where lower filtering impedance is specified.

Both parts maintain identical current handling capacity (2A), DC resistance (200 mOhm), and thermal operating range (-55°C ~ 105°C), ensuring equivalent thermal and electrical stress characteristics in the circuit.

Frequently Asked Questions (FAQ)

Q: Can the 7116-RC replace the 7121-RC in any application?

A: The 7116-RC can replace the 7121-RC only if the circuit design permits operation at 6.8 mH inductance instead of 42.5 mH. The lower inductance will reduce EMI filtering effectiveness proportionally. All other electrical parameters (current, resistance, temperature range) are identical.

Q: Are there physical space considerations when substituting these parts?

A: Yes. The 7121-RC measures 1.230" diameter with 1.230" maximum height, while the 7116-RC measures 0.900" diameter with 0.900" maximum height. The 7116-RC occupies less board space and may fit in applications with tighter layout constraints.

Q: Do both parts have the same pin configuration?

A: Yes. Both parts use a Vertical, No Base, 4 PC Pin package configuration, ensuring identical PCB footprint and soldering requirements.

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

A: No. Both parts are ROHS3 compliant, REACH unaffected, and carry identical regulatory classifications (ECCN EAR99, HTSUS 8548.00.0000).

Q: What is the DC resistance specification for both parts?

A: Both the 7121-RC and 7116-RC have a maximum DC resistance of 200 mOhm, ensuring equivalent power dissipation characteristics at rated current.