SXR681M035ST Equivalent & Substitute Parts

Part Overview

The SXR681M035ST is a 680 µF, 35 V aluminum electrolytic capacitor manufactured by Cornell Dubilier Electronics (CDE) in a radial, through-hole configuration. This component is classified as obsolete, making equivalent and substitute parts necessary for ongoing maintenance, repair, and legacy system support. The part operates across a temperature range of -40°C to 105°C with a rated lifetime of 4000 hours at 105°C, suitable for general-purpose applications requiring stable capacitance and low equivalent series resistance.

Substiute Parts

SXR681M035ST

Cornell Dubilier Electronics (CDE)In Stock: 1085SXR681M035ST Datasheet

Current PartRFQ

UPW1H681MHD

NichiconIn Stock: 9125UPW1H681MHD Datasheet

UpgradeRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SXR681M035ST is determined by strict adherence to the following electrical and mechanical parameters:

Critical Matching Parameters:

• Capacitance: 680 µF (exact match required)
• Tolerance: ±20% (exact match required)
• Mounting Type: Through Hole (exact match required)
• Package / Case: Radial, Can (exact match required)
• Lead Spacing: 0.197" (5.00 mm) (exact match required)
• Polarization: Polar (exact match required)

Allowable Upgrade Parameters:

• Voltage - Rated: Equal to or greater than 35 V
• Operating Temperature Range: Equal to or wider than -40°C ~ 105°C
• Lifetime @ Temperature: Equal to or greater than 4000 Hrs @ 105°C
• ESR: Equal to or lower than 230 mOhm @ 120 Hz
• Ripple Current: Equal to or greater than specified values

Physical Tolerance:

• Diameter and height may vary within standard manufacturing tolerances for the same package class, provided the component fits within the PCB footprint and mounting constraints of the original design.

The substitute part UPW1H681MHD from Nichicon meets all critical matching parameters and provides upgrades in voltage rating (50 V vs. 35 V), operating temperature range (-55°C ~ 105°C vs. -40°C ~ 105°C), and lifetime (7000 Hrs @ 105°C vs. 4000 Hrs @ 105°C).

Parameter Comparison

Engineering Selection Recommendations

The SXR681M035ST is classified as obsolete, necessitating the use of substitute components for new procurement and system maintenance. The UPW1H681MHD from Nichicon is a direct functional substitute that maintains all critical electrical and mechanical parameters while providing performance enhancements.

Compliance and Certification: Both the original SXR681M035ST and the substitute UPW1H681MHD are ROHS3 compliant, meeting environmental and regulatory requirements for electronic component use. The UPW1H681MHD carries REACH Unaffected status, confirming compliance with chemical substance regulations.

Product Status Consideration: The UPW1H681MHD is designated as "Not For New Designs," indicating that while it remains available for replacement and maintenance applications, it may not be the optimal choice for new product development. For legacy system support and field replacements, this component is suitable. For new designs, consultation with the manufacturer or evaluation of current-generation alternatives is recommended based on application requirements.

Physical Compatibility: The diameter difference between the SXR681M035ST (0.472" / 12.00 mm) and UPW1H681MHD (0.492" / 12.50 mm) is within standard manufacturing tolerances for radial can capacitors. Lead spacing and height are identical, ensuring PCB footprint compatibility. Verify mounting clearance in the specific application to confirm physical fit.

Frequently Asked Questions (FAQ)

Q: Can the UPW1H681MHD directly replace the SXR681M035ST in my circuit?

A: Yes, the UPW1H681MHD is a direct functional substitute. It maintains identical capacitance (680 µF), tolerance (±20%), lead spacing (5.00 mm), and mounting type (through-hole radial). The higher voltage rating (50 V vs. 35 V) and extended lifetime (7000 Hrs vs. 4000 Hrs @ 105°C) provide performance upgrades. Verify physical clearance due to the 0.02" (0.50 mm) diameter increase.

Q: What is the significance of the voltage rating difference?

A: The UPW1H681MHD operates at 50 V, compared to the original 35 V rating. This higher voltage rating provides additional safety margin in circuits operating at or near the original 35 V specification. The substitute will not degrade performance in applications designed for 35 V operation.

Q: Does the lower ESR of the UPW1H681MHD affect circuit performance?

A: The UPW1H681MHD specifies impedance at 50 mOhms, compared to the SXR681M035ST's ESR of 230 mOhm @ 120 Hz. Lower ESR generally improves capacitor performance by reducing heat generation and improving transient response. This is a beneficial characteristic for most applications.

Q: Are there any temperature range considerations?

A: The UPW1H681MHD operates across -55°C ~ 105°C, compared to the SXR681M035ST's -40°C ~ 105°C range. The extended lower temperature limit provides additional operational margin. Both components operate identically at the upper temperature limit of 105°C.

Q: What does "Not For New Designs" mean for the UPW1H681MHD?

A: This designation indicates the component is available for replacement and maintenance applications but may not be recommended for new product development. For legacy system support and field replacements, this component is suitable. Evaluate current-generation alternatives for new designs.

Q: How do the ripple current ratings compare?

A: The UPW1H681MHD provides higher ripple current capacity at both 120 Hz (1.38 A vs. 660 mA) and 100 kHz (1.84 A vs. 1.32 A). This enhanced ripple current handling improves performance in high-frequency switching applications and reduces thermal stress.

Q: Is the physical size difference critical?

A: The diameter increases from 0.472" to 0.492" (0.50 mm difference). Lead spacing and height remain identical. Verify mounting clearance in your specific PCB layout and enclosure design. In most applications, this minor increase poses no compatibility issues.

Q: Are both components RoHS compliant?

A: Yes, both the SXR681M035ST and UPW1H681MHD are ROHS3 compliant. The UPW1H681MHD additionally carries REACH Unaffected status, confirming compliance with chemical substance regulations.