NLW40-25 Equivalent & Substitute Parts

Part Overview

The NLW40-25 is a 40 µF, 25 V aluminum electrolytic capacitor in axial, can package manufactured by Cornell Dubilier Electronics (CDE). This component is classified as obsolete, indicating discontinued production and limited availability in the supply chain. The part operates across a temperature range of -40°C to 105°C with a rated lifetime of 1000 hours at 105°C. Due to its obsolete status, identifying equivalent substitute parts with compatible electrical and mechanical characteristics is necessary for design continuity and procurement planning.

Substiute Parts

NLW40-25

Cornell Dubilier Electronics (CDE)In Stock: 1093NLW40-25 Datasheet

Current PartRFQ

476TMA050M

Cornell Dubilier / Illinois CapacitorIn Stock: 6176476TMA050M Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the NLW40-25 is determined by the following critical parameters:

Electrical Compatibility Criteria:

• Capacitance value must accommodate circuit tolerance requirements
• Rated voltage must equal or exceed the original specification (25 V minimum)
• ESR characteristics must support ripple current handling at operating frequencies
• Operating temperature range must cover -40°C to 105°C minimum
• Polarization must remain polar (electrolytic)

Mechanical Compatibility Criteria:

• Package type must be axial, can configuration
• Mounting type must be through-hole
• Physical dimensions must fit within PCB layout constraints

Compliance Criteria:

• RoHS3 compliance required
• Active or current product status preferred for long-term availability

The substitute part 476TMA050M meets these criteria with the following allowances: capacitance increase from 40 µF to 47 µF (within tolerance margin for general-purpose applications), voltage rating increase from 25 V to 50 V (provides design margin), and improved ESR and lifetime specifications.

Parameter Comparison

Engineering Selection Recommendations

Substitution Feasibility:

The 476TMA050M is a valid substitute for the NLW40-25 based on the following engineering factors:

1. Electrical Parameters: The substitute provides equal or superior electrical performance across all measured parameters. The 47 µF capacitance represents a 17.5% increase over the original 40 µF specification. For general-purpose applications, this variance falls within acceptable tolerance margins. The 50 V rated voltage provides a 100% design margin above the original 25 V specification, enhancing circuit reliability.

2. Thermal and Lifetime Performance: The substitute demonstrates improved thermal characteristics with a 2000-hour lifetime at 105°C compared to the original 1000-hour rating. Operating temperature range remains identical at -40°C to 105°C.

3. Ripple Current Capability: ESR is reduced by 37% (from 6.7 Ohm to 4.233 Ohm at 120 Hz), resulting in improved ripple current handling and reduced heat generation.

4. Regulatory Compliance: Both parts maintain ROHS3 compliance, satisfying environmental and regulatory requirements.

5. Product Availability: The substitute is in active production status with 6111 units in stock, compared to the obsolete NLW40-25. This ensures long-term procurement viability and supply chain continuity.

6. Physical Compatibility: The substitute is physically smaller (0.248" Dia x 0.630" L versus 0.340" Dia x 0.760" L), ensuring it fits within the original PCB layout without modification.

Application-Specific Considerations:

For bypass and decoupling applications, the 476TMA050M is directly suitable. For circuits with strict capacitance tolerance requirements, the tolerance difference (-10%, +75% versus ±20%) must be evaluated against circuit specifications.

Frequently Asked Questions (FAQ)

Q: Can the 476TMA050M directly replace the NLW40-25 without PCB modification?

A: Yes. The substitute is physically smaller and maintains identical through-hole axial, can package configuration. No PCB layout changes are required.

Q: Why is the capacitance value different (47 µF vs. 40 µF)?

A: The 17.5% capacitance increase falls within acceptable tolerance for general-purpose applications. For circuits requiring exact capacitance values, verify that the circuit design accommodates this variance. The original NLW40-25 tolerance of -10%, +75% already permits significant capacitance variation.

Q: Does the higher voltage rating (50 V vs. 25 V) affect circuit operation?

A: No. A higher voltage rating does not affect circuit operation when the applied voltage remains at or below 25 V. The 50 V rating provides additional design margin and improves component reliability.

Q: What is the impact of the lower ESR (4.233 Ohm vs. 6.7 Ohm)?

A: Lower ESR reduces heat generation and improves ripple current handling capability. This is a performance improvement with no negative impact on circuit operation.

Q: Are both parts RoHS3 compliant?

A: Yes. Both the NLW40-25 and 476TMA050M are ROHS3 compliant, meeting environmental and regulatory requirements.

Q: Why is the NLW40-25 obsolete?

A: The NLW40-25 is classified as obsolete, indicating discontinued production by Cornell Dubilier Electronics. The 476TMA050M is an active product in current production, ensuring availability for future procurement needs.

Q: Can the 476TMA050M be used in high-frequency ripple current applications?

A: Yes. The substitute is rated for 200 mA ripple current at 50 kHz, compared to the original 112.7 mA at 10 kHz, demonstrating superior high-frequency performance.

Q: What tolerance difference exists between the two parts?

A: The NLW40-25 has -10%, +75% tolerance, while the 476TMA050M has ±20% tolerance. For applications requiring tight capacitance control, verify that the ±20% tolerance of the substitute meets circuit specifications.