RC12KB120R Equivalent & Substitute Parts

Part Overview

The RC12KB120R is a 120 Ohms ±10% 0.5W axial through-hole resistor manufactured by Stackpole Electronics Inc. This carbon composition resistor features non-inductive and pulse withstanding characteristics, with an operating temperature range of -55°C to 125°C. The product is currently obsolete, making identification of suitable substitute components essential for ongoing maintenance, repair, and legacy system support.

Substiute Parts

RC12KB120R

Stackpole Electronics IncIn Stock: 815RC12KB120R Datasheet

Current PartRFQ

ASRM12JB120R

Stackpole Electronics IncIn Stock: 1047ASRM12JB120R Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the RC12KB120R is determined by the following critical parameters:

• Resistance Value: 120 Ohms (exact match required)
• Power Rating: 0.5W minimum (equal or greater acceptable)
• Package Type: Axial through-hole configuration
• Tolerance: ±10% or better (tighter tolerance acceptable)
• Operating Temperature Range: Must encompass or exceed -55°C ~ 125°C
• Termination Count: 2-pin axial configuration
• Compliance: RoHS3 compliance maintained

The ASRM12JB120R qualifies as a direct substitute based on matching resistance, power rating, axial package, and operating temperature specifications. The substitute offers improved tolerance (±5% versus ±10%) and extended upper temperature rating (155°C versus 125°C), with active product status ensuring continued availability.

Parameter Comparison

Engineering Selection Recommendations

The ASRM12JB120R is the manufacturer-recommended substitute for the obsolete RC12KB120R. Both components are manufactured by Stackpole Electronics Inc and maintain identical resistance values and power ratings in axial through-hole configuration.

The substitute offers technical advantages including tighter tolerance specification (±5% versus ±10%), extended operating temperature range (155°C upper limit versus 125°C), and active product status ensuring long-term availability. The metal film composition of the substitute provides improved stability characteristics compared to the carbon composition of the original part.

Physical dimensions differ slightly between the two components. The substitute is marginally smaller (0.118" diameter versus 0.142" diameter), which may require board layout verification in space-constrained applications. Both components maintain two-pin axial termination configuration compatible with standard through-hole mounting.

Frequently Asked Questions (FAQ)

Q: Can the ASRM12JB120R directly replace the RC12KB120R in existing designs?

A: Yes. Both components share identical resistance values (120 Ohms), power ratings (0.5W), and axial through-hole package configuration. The substitute meets or exceeds all critical electrical parameters of the original part.

Q: What is the significance of the tolerance difference (±10% versus ±5%)?

A: The substitute offers tighter tolerance, meaning the actual resistance value will be closer to the nominal 120 Ohms specification. This represents an improvement over the original part and is fully compatible with circuit designs that accepted the original ±10% tolerance.

Q: Are there physical mounting differences between these components?

A: The substitute is slightly smaller in diameter (0.118" versus 0.142"). In most applications, this presents no compatibility issue. However, designs with tight mechanical constraints or specific lead spacing requirements should verify board layout compatibility.

Q: What is the difference between carbon composition and metal film resistor types?

A: Both are axial through-hole resistor technologies. Metal film resistors (ASRM12JB120R) typically offer better frequency response and lower noise characteristics. Carbon composition resistors (RC12KB120R) provide pulse withstanding capability. The substitute maintains pulse withstanding features while offering metal film construction benefits.

Q: Is the substitute RoHS compliant?

A: The original RC12KB120R is ROHS3 compliant. Compliance information for the substitute is not provided in the available data. Verification with the manufacturer or distributor is necessary if RoHS compliance is a design requirement.

Q: What is the temperature coefficient difference?

A: The substitute specifies 0/-1800ppm/°C temperature coefficient. The original part does not provide this specification. The substitute's defined temperature coefficient indicates predictable resistance variation across the operating temperature range.