337LMB400M2ED Equivalent & Substitute Parts

Part Overview

The 337LMB400M2ED is a 330 µF, 400 V aluminum electrolytic capacitor manufactured by Cornell Dubilier / Illinois Capacitor in the LMB series. This radial, can snap-in component is designed for general purpose applications with a rated lifetime of 3000 hours at 105°C and an operating temperature range of -25°C to 105°C. The part is currently active in production with ROHS3 compliance and REACH unaffected status. Alternative equivalent parts are necessary when the primary part becomes unavailable, when design flexibility is required across multiple supply sources, or when specific electrical performance parameters (such as ESR or ripple current characteristics) must be optimized for circuit requirements.

Substiute Parts

337LMB400M2ED

Cornell Dubilier / Illinois CapacitorIn Stock: 1180337LMB400M2ED Datasheet

Current PartRFQ

LQSW6331MELC30

NichiconIn Stock: 274056LQSW6331MELC30 Datasheet

UpgradeRFQ

381LR331M400A022

Cornell Dubilier Electronics (CDE)In Stock: 600219381LR331M400A022 Datasheet

Parametric EquivalentRFQ

B43254C9337M000

EPCOS - TDK ElectronicsIn Stock: 1196B43254C9337M000 Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 337LMB400M2ED is determined by strict compliance with the following parameters:

Critical Parameters (Must Match Exactly):

• Capacitance: 330 µF
• Tolerance: ±20%
• Voltage Rating: 400 V (or higher)
• Package Type: Radial, Can - Snap-In
• Mounting Type: Through Hole
• Physical Dimensions: 1.378" Dia (35.00mm) and 1.260" Height (32.00mm)
• Lead Spacing: 0.394" (10.00mm)

Performance Parameters (Within Design Margins):

• Operating Temperature Range: -25°C ~ 105°C
• Lifetime: 3000 Hrs @ 105°C
• Polarization: Polar

Substitute parts are classified into two categories: upgrade parts with higher voltage ratings that provide enhanced reliability margins, and parametric equivalents that match the exact 400 V specification with equivalent or superior electrical performance characteristics.

Parameter Comparison

Engineering Selection Recommendations

Primary Selection (337LMB400M2ED or 381LR331M400A022): The 337LMB400M2ED and 381LR331M400A022 are equivalent selections for new designs. Both parts are active products with ROHS3 compliance and identical electrical specifications (330 µF, ±20%, 400 V, 3000 Hrs @ 105°C). The 381LR331M400A022 offers superior ESR performance (402 mOhm versus 1.25596 Ohm) and higher ripple current ratings at 120 Hz and 20 kHz, making it suitable for applications requiring lower impedance or higher ripple current tolerance.

Upgrade Option (LQSW6331MELC30): The LQSW6331MELC30 from Nichicon provides a voltage rating upgrade to 420 V while maintaining the same 330 µF capacitance, ±20% tolerance, and 3000 Hrs @ 105°C lifetime specification. This part is an active product suitable for applications where an enhanced voltage margin is required. Physical dimensions and mounting characteristics are identical to the primary part.

Legacy Status (B43254C9337M000): The B43254C9337M000 from EPCOS - TDK Electronics is marked as "Not For New Designs" and should not be selected for new circuit implementations. This part is available only for legacy system support or maintenance applications where continued compatibility with existing designs is required.

Frequently Asked Questions (FAQ)

Q: Can the LQSW6331MELC30 (420 V) replace the 337LMB400M2ED (400 V)? A: Yes. The LQSW6331MELC30 is a direct mechanical and electrical substitute with identical 330 µF capacitance, ±20% tolerance, and 3000 Hrs @ 105°C lifetime. The higher 420 V rating provides additional voltage margin for the same application circuit. All physical dimensions, lead spacing, and mounting characteristics are identical.

Q: What is the difference between parametric equivalents and upgrade parts? A: Parametric equivalents (381LR331M400A022, B43254C9337M000) match the exact 400 V voltage specification of the original part. The upgrade part (LQSW6331MELC30) provides a higher voltage rating (420 V) for applications requiring enhanced reliability margins. All four parts share identical 330 µF capacitance, physical dimensions, and mounting type.

Q: Are all substitute parts interchangeable in the 337LMB400M2ED circuit location? A: All substitute parts have identical physical dimensions (1.378" Dia, 1.260" Height, 0.394" lead spacing), mounting type (Through Hole), and package configuration (Radial, Can - Snap-In). They are mechanically and electrically interchangeable in the PCB layout without modification.

Q: What does "Not For New Designs" mean for the B43254C9337M000? A: This designation indicates the part is legacy status. It should not be used in new product development but may be used for field repairs or maintenance of existing systems using this component. For new designs, select the 337LMB400M2ED, 381LR331M400A022, or LQSW6331MELC30.

Q: How does ESR affect component selection? A: Equivalent Series Resistance (ESR) influences ripple current handling and heat dissipation. The 381LR331M400A022 has the lowest specified ESR at 402 mOhm @ 120 Hz, reducing heat generation in high ripple current applications. The 337LMB400M2ED shows higher ESR at 1.25596 Ohm, still within acceptable range for general purpose applications. Parts without specified ESR values must be evaluated against your specific ripple current requirements.

Q: What inventory availability should influence my selection? A: The 381LR331M400A022 provides the highest inventory availability at 600,200 units, followed by LQSW6331MELC30 at 273,982 units, the primary part (337LMB400M2ED) at 1,112 units, and B43254C9337M000 at 1,130 units. For applications with high volume requirements, the 381LR331M400A022 offers superior supply security.