7B-26.000MBBK-T Crystal Oscillator Equivalent & Substitute Parts

Part Overview

The 7B-26.000MBBK-T is a 26 MHz fundamental mode crystal oscillator manufactured by TXC CORPORATION, designed for surface mount applications in 4-SMD, No Lead packaging. This component operates at 26 MHz with ±50ppm frequency stability and 20pF load capacitance. The part is classified as Obsolete, necessitating identification of active equivalent alternatives that maintain electrical and mechanical compatibility for ongoing production and field replacement requirements.

Substiute Parts

7B-26.000MBBK-T

TXC CORPORATIONIn Stock: 8477B-26.000MBBK-T Datasheet

Current PartRFQ

7M-26.000MBBK-T

TXC CORPORATIONIn Stock: 7207M-26.000MBBK-T Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 7B-26.000MBBK-T is based on strict electrical and mechanical parameter matching within the TXC CORPORATION crystal product family. The following criteria determine valid substitutes:

Mandatory Matching Parameters:

• Frequency: 26.0000 MHz (exact match required)
• Frequency Stability: ±50ppm (tolerance specification must be met or exceeded)
• Load Capacitance: 20pF (circuit design dependent)
• Operating Temperature Range: -20°C to 70°C (minimum requirement)
• Mounting Type: Surface Mount
• Package Type: 4-SMD, No Lead configuration
• RoHS Compliance: Required for regulatory alignment

Allowable Variation Parameters:

• ESR (Equivalent Series Resistance): Variation permitted within oscillator circuit design margins
• Physical Dimensions: Variation acceptable if package type and mounting interface remain compatible
• Product Status: Active status preferred for long-term availability

The 7M-26.000MBBK-T qualifies as a direct substitute based on matching all mandatory parameters while offering improved product status (Active vs. Obsolete).

Parameter Comparison

Engineering Selection Recommendations

Primary Substitute: 7M-26.000MBBK-T

The 7M-26.000MBBK-T is the recommended substitute for the obsolete 7B-26.000MBBK-T based on the following engineering criteria:

1. Electrical Compatibility: All critical electrical parameters match exactly—frequency, frequency stability, load capacitance, and operating temperature range are identical. The ESR variation (40 Ohms to 60 Ohms) falls within acceptable oscillator circuit design margins for fundamental mode crystals in this frequency range.

2. Physical Compatibility: Both parts use identical 4-SMD, No Lead packaging with surface mount configuration. The 7M series offers a smaller footprint (3.20mm x 2.50mm vs. 5.00mm x 3.20mm) and lower profile (0.80mm vs. 1.05mm), providing layout optimization benefits without requiring circuit redesign.

3. Regulatory Compliance: Both parts maintain RoHS compliance and MSL 1 (Unlimited) rating, ensuring regulatory alignment and simplified handling procedures.

4. Product Availability: The 7M-26.000MBBK-T carries Active product status with 670 units in stock, providing long-term supply continuity compared to the Obsolete 7B series.

5. Certification Alignment: The substitute maintains REACH Unaffected status and identical ECCN/HTSUS classifications, supporting seamless integration into existing supply chain and compliance documentation.

Frequently Asked Questions (FAQ)

Q: Can the 7M-26.000MBBK-T be used as a direct replacement for the 7B-26.000MBBK-T without circuit modification?

A: Yes. The 7M-26.000MBBK-T is a direct electrical substitute. Both parts operate at 26 MHz with ±50ppm stability and 20pF load capacitance. The ESR difference (40 Ohms vs. 60 Ohms) is within acceptable design margins for fundamental mode crystal oscillators. No circuit redesign is required.

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

A: ESR (Equivalent Series Resistance) affects crystal oscillator startup time and power consumption. The 7M series has 60 Ohms ESR compared to 40 Ohms in the 7B series. This 20-Ohm increase is typical within TXC product families and does not compromise oscillator performance in standard applications. Verify ESR compatibility only if your circuit operates at frequency extremes or with marginal oscillator drive levels.

Q: Are there physical footprint considerations when substituting the 7M for the 7B?

A: Yes. The 7M-26.000MBBK-T has a smaller footprint (3.20mm x 2.50mm vs. 5.00mm x 3.20mm) and lower height (0.80mm vs. 1.05mm). This allows direct substitution on existing PCBs with potential layout optimization. Verify that your PCB pad layout accommodates the smaller 7M dimensions. If the original PCB was designed for the larger 7B footprint, the 7M will fit within the allocated space.

Q: Does the substitute part maintain the same regulatory certifications?

A: Yes. The 7M-26.000MBBK-T maintains identical RoHS compliance, MSL 1 rating, ECCN (EAR99), and HTSUS classification (8541.60.0060). REACH status is listed as Unaffected, supporting regulatory continuity.

Q: What is the inventory status for the substitute part?

A: The 7M-26.000MBBK-T is classified as Active with 670 units in stock, providing reliable long-term availability compared to the Obsolete 7B series (792 units remaining).

Q: Are there any other TXC 26 MHz crystal alternatives beyond the 7M series?

A: Based on the provided data, the 7M-26.000MBBK-T is the specified substitute. Additional alternatives may exist within TXC's product portfolio; however, only parts meeting all mandatory electrical and mechanical parameters should be considered for direct substitution.