Equivalent & Substitute Parts for 1812J1K20331MXT

Part Overview

The 1812J1K20331MXT is a 330 pF ceramic capacitor manufactured by Knowles Syfer, rated for 1200V (1.2kV) operation with X7R temperature coefficient characteristics. This surface mount multilayer ceramic capacitor (MLCC) in 1812 (4532 Metric) package is designed for general purpose applications requiring stable capacitance across the operating temperature range of -55°C to 125°C. The part is currently active in production with ROHS3 compliance and unlimited moisture sensitivity rating (MSL 1). Substitute parts are identified when equivalent capacitance and package specifications are maintained while offering alternative voltage ratings or temperature coefficient options that satisfy circuit requirements.

Substiute Parts

1812J1K20331MXT

Knowles SyferIn Stock: 10201812J1K20331MXT Datasheet

Current PartRFQ

C1812C331JHGAC7800

KEMETIn Stock: 1332C1812C331JHGAC7800 Datasheet

MFR RecommendedRFQ

C1812C331JZGAC7800

KEMETIn Stock: 1407C1812C331JZGAC7800 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the 1812J1K20331MXT are qualified based on the following criteria:

Mandatory Matching Parameters:

• Capacitance: 330 pF (exact match required)
• Package / Case: 1812 (4532 Metric) (exact match required)
• Mounting Type: Surface Mount, MLCC (exact match required)
• Operating Temperature Range: -55°C to 125°C (exact match required)
• RoHS Status: ROHS3 Compliant (exact match required)
• Moisture Sensitivity Level: 1 (Unlimited) (exact match required)

Allowable Variation Parameters:

• Voltage Rating: May exceed the original 1200V specification
• Temperature Coefficient: May differ (C0G/NP0 acceptable as alternative to X7R)
• Tolerance: May be tighter (±5% acceptable as alternative to ±20%)

The two identified substitutes from KEMET maintain all mandatory parameters while offering enhanced voltage ratings and improved temperature stability through C0G/NP0 temperature coefficient, making them suitable for applications requiring higher voltage margins or superior capacitance stability.

Parameter Comparison

Engineering Selection Recommendations

Both KEMET substitutes maintain full compliance with ROHS3 and REACH regulations, matching the original part's environmental and regulatory status. The C1812C331JHGAC7800 provides the highest voltage margin at 3000V, suitable for applications requiring maximum overvoltage protection. The C1812C331JZGAC7800 offers a balanced approach with 2500V rating and the thinnest profile at 0.071" (1.80mm), beneficial for space-constrained designs. Both substitutes feature C0G/NP0 temperature coefficient with ±5% tolerance, delivering superior capacitance stability compared to the X7R/±20% specification of the original part. Selection between substitutes depends on circuit voltage requirements and available PCB height clearance.

Frequently Asked Questions (FAQ)

Q: Can C1812C331JHGAC7800 or C1812C331JZGAC7800 be used as direct replacements for 1812J1K20331MXT?

A: Yes, both KEMET parts are direct substitutes. They maintain identical capacitance (330 pF), package (1812/4532 Metric), mounting type (Surface Mount MLCC), operating temperature range (-55°C to 125°C), and regulatory compliance (ROHS3, REACH Unaffected, MSL 1). The higher voltage ratings and improved temperature coefficient represent enhancements rather than deviations.

Q: What is the difference between X7R and C0G/NP0 temperature coefficients?

A: X7R provides ±15% capacitance variation across the -55°C to 125°C operating range. C0G/NP0 provides superior stability with minimal capacitance drift across temperature. C0G/NP0 is preferred in precision applications where capacitance stability is critical.

Q: Are there physical compatibility concerns when substituting these parts?

A: The footprint remains identical (1812/4532 Metric, 0.177" L x 0.126" W). Thickness varies: original part is 0.098" (2.50mm), C1812C331JHGAC7800 is 0.106" (2.70mm), and C1812C331JZGAC7800 is 0.071" (1.80mm). Verify PCB clearance for the thicker KEMET part; the thinner option provides additional design margin.

Q: Why would I choose the 2.5kV substitute over the 3kV option?

A: The C1812C331JZGAC7800 (2.5kV) offers the thinnest profile at 0.071" (1.80mm), making it optimal for applications with height constraints. The 2.5kV rating still exceeds the original 1.2kV specification, providing adequate voltage margin for most general purpose applications.

Q: Are all parts available in Tape & Reel (TR) packaging?

A: Yes, all three parts are supplied in Tape & Reel packaging suitable for automated assembly processes.