9B-12.000MAAJ-B Crystal Oscillator Equivalent & Substitute Parts

Part Overview

The 9B-12.000MAAJ-B is a 12 MHz through-hole crystal manufactured by TXC CORPORATION in the HC-49/US package. This component is classified as obsolete product status. The part operates at a fundamental frequency with ±30ppm stability and 18pF load capacitance, designed for applications requiring precise timing in the 12 MHz range. Due to its obsolete classification, identifying equivalent substitute parts with matching electrical and mechanical specifications is necessary for design continuity and procurement planning.

Substiute Parts

9B-12.000MAAJ-B

TXC CORPORATIONIn Stock: 8919B-12.000MAAJ-B Datasheet

Current PartRFQ

HC49US-FF3F18-12.000MHZ

ILSIIn Stock: 1420HC49US-FF3F18-12.000MHZ Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 9B-12.000MAAJ-B is determined by the following critical parameters:

Mandatory Matching Parameters:

• Frequency: 12.0000 MHz
• Frequency Stability: ±30ppm
• Load Capacitance: 18pF
• Operating Mode: Fundamental
• Operating Temperature Range: -20°C to +70°C
• Mounting Type: Through Hole
• Package / Case: HC-49/US

Allowable Variation Parameters:

• ESR (Equivalent Series Resistance): Variation permitted within circuit design tolerance
• Physical dimensions: Minor variations acceptable within HC-49/US standard envelope
• Manufacturer: Different manufacturers acceptable if electrical specifications match

The substitute part HC49US-FF3F18-12.000MHZ from ILSI meets all mandatory matching parameters. The ESR difference (60 Ohms versus 40 Ohms) falls within acceptable substitution criteria for through-hole crystal applications, as ESR variation of this magnitude does not affect fundamental frequency stability or load capacitance performance in standard oscillator circuits.

Parameter Comparison

Engineering Selection Recommendations

Primary Substitute: HC49US-FF3F18-12.000MHZ (ILSI)

The HC49US-FF3F18-12.000MHZ from ILSI is the qualified substitute for the obsolete 9B-12.000MAAJ-B. Selection rationale:

1. Product Status: The ILSI part maintains Active product status, ensuring ongoing availability and supply chain continuity.

2. Electrical Equivalence: All critical electrical parameters match exactly: 12 MHz frequency, ±30ppm stability, 18pF load capacitance, and fundamental operating mode. The 20-Ohm ESR increase (40 to 60 Ohms) is within acceptable tolerance for through-hole crystal applications.

3. Compliance Alignment: Both parts are ROHS3 Compliant and share identical ECCN (EAR99) and HTSUS (8541.60.0050) classifications, ensuring regulatory and trade compliance equivalence.

4. Mechanical Compatibility: Both parts use HC-49/US package with compatible through-hole mounting. Physical dimensions remain within standard HC-49/US envelope specifications.

5. Inventory Availability: The ILSI substitute maintains higher inventory levels (1365 Pcs) compared to the obsolete TXC part (836 Pcs), supporting procurement reliability.

Frequently Asked Questions (FAQ)

Q: Can the HC49US-FF3F18-12.000MHZ substitute directly for the 9B-12.000MAAJ-B in existing designs?

A: Yes. The substitute part matches all mandatory electrical specifications (frequency, stability, load capacitance, operating mode, temperature range) and uses the identical HC-49/US through-hole package. Direct substitution is supported without circuit redesign.

Q: What is the significance of the 20-Ohm ESR difference between the two parts?

A: ESR variation of this magnitude does not affect fundamental frequency stability or load capacitance performance in standard oscillator circuits. The 60-Ohm ESR of the ILSI part remains within acceptable operating parameters for 12 MHz through-hole crystal applications.

Q: Are there any compliance or certification differences between the two parts?

A: No. Both parts are ROHS3 Compliant and share identical ECCN and HTSUS classifications. The ILSI part is REACH Unaffected, while the TXC part is REACH Affected; however, this does not affect substitution eligibility for applications already using the obsolete part.

Q: Will the physical dimension differences affect PCB layout?

A: No. Both parts conform to HC-49/US standard package specifications. The minor dimensional variations (11.50mm vs 11.10mm length; 5.00mm vs 4.70mm width; 3.68mm vs 3.50mm height) remain within standard envelope tolerances and do not require PCB layout modification.

Q: What is the packaging difference between the two parts?

A: The 9B-12.000MAAJ-B is supplied with standard packaging, while the HC49US-FF3F18-12.000MHZ is supplied in Bulk packaging. Both formats are suitable for through-hole assembly processes.

Q: Is the ILSI part suitable for new designs or only as a replacement for obsolete inventory?

A: The HC49US-FF3F18-12.000MHZ is suitable for both applications. Its Active product status and higher inventory availability make it appropriate for new design implementations requiring 12 MHz ±30ppm crystals in HC-49/US through-hole packages.