7B-27.000MBBK-T 27 MHz Crystal Equivalent & Substitute Parts

Part Overview

The 7B-27.000MBBK-T is a 27 MHz fundamental mode crystal oscillator manufactured by TXC CORPORATION, designed for surface mount applications in 4-SMD, No Lead package configuration. This part operates at 27.0000 MHz with ±50ppm frequency stability and 20pF load capacitance. The product is currently classified as Obsolete, necessitating identification of active equivalent and substitute components that maintain electrical and mechanical compatibility for ongoing production and field replacement requirements.

Substiute Parts

7B-27.000MBBK-T

TXC CORPORATIONIn Stock: 10447B-27.000MBBK-T Datasheet

Current PartRFQ

7M-27.000MBBK-T

TXC CORPORATIONIn Stock: 9757M-27.000MBBK-T Datasheet

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ECS-270-20-33-TR

ECS Inc.In Stock: 30342ECS-270-20-33-TR Datasheet

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H130B-27.000-20-F-TR

Raltron ElectronicsIn Stock: 2052H130B-27.000-20-F-TR Datasheet

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Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 7B-27.000MBBK-T is determined by strict adherence to the following electrical and mechanical parameters:

Critical Matching Parameters:

• Frequency: 27.0000 MHz (exact match required)
• Frequency Stability: ±50ppm (exact match required)
• Load Capacitance: 20pF (exact match required)
• Operating Mode: Fundamental (exact match required)
• Operating Temperature Range: -20°C to 70°C (exact match required)
• Package / Case: 4-SMD, No Lead (exact match required)
• Mounting Type: Surface Mount (exact match required)

Allowable Variation Parameters:

• ESR (Equivalent Series Resistance): Variation permitted within component design specifications
• Physical Dimensions: Variation permitted provided 4-SMD, No Lead package compatibility is maintained
• Height - Seated (Max): Variation permitted within PCB assembly constraints
• Packaging Format: Cut Tape (CT) & Digi-Reel® or Tape & Reel (TR) formats are interchangeable for procurement purposes

All three substitute parts meet the critical matching parameters and are therefore electrically and mechanically compatible with the 7B-27.000MBBK-T.

Parameter Comparison

Engineering Selection Recommendations

Product Status Consideration: The 7B-27.000MBBK-T is classified as Obsolete. All three substitute parts are classified as Active, ensuring long-term availability and continued manufacturing support. Selection of an Active product status component is required for new designs and ongoing production requirements.

Compliance and Certification: All substitute parts maintain Moisture Sensitivity Level (MSL) 1 classification, indicating unlimited shelf life and no special moisture control requirements during storage and handling. The 7M-27.000MBBK-T maintains RoHS Compliant status consistent with the main part. The ECS-270-20-33-TR and H130B-27.000-20-F-TR are ROHS3 Compliant, representing current regulatory compliance standards. All parts carry REACH Unaffected or equivalent status where specified.

ESR Variation: The three substitute parts exhibit ESR values of 60 Ohms (7M-27.000MBBK-T), 40 Ohms (ECS-270-20-33-TR), and 20 Ohms (H130B-27.000-20-F-TR), compared to the main part's 40 Ohms specification. ESR variation within this range is permissible for 27 MHz crystal applications operating at the specified load capacitance and frequency stability parameters.

Physical Dimensions: The 7M-27.000MBBK-T and ECS-270-20-33-TR feature reduced footprint dimensions (3.20mm x 2.50mm) compared to the main part and H130B-27.000-20-F-TR (5.00mm x 3.20mm). PCB layout compatibility must be evaluated based on specific application requirements. Height differences (0.80mm to 1.05mm) are within typical assembly clearance tolerances.

Inventory Availability: ECS-270-20-33-TR demonstrates highest inventory availability (30,300 pcs), followed by 7M-27.000MBBK-T (911 pcs) and H130B-27.000-20-F-TR (2,024 pcs), providing multiple sourcing options for supply chain continuity.

Frequently Asked Questions (FAQ)

Q: Can the 7M-27.000MBBK-T directly replace the 7B-27.000MBBK-T?

A: Yes. Both parts share identical electrical specifications: 27.0000 MHz frequency, ±50ppm stability, 20pF load capacitance, and Fundamental operating mode. The 7M-27.000MBBK-T is Active status, addressing the Obsolete status of the main part. Physical dimensions differ (3.20mm x 2.50mm versus 5.00mm x 3.20mm), requiring PCB layout verification. ESR increases from 40 Ohms to 60 Ohms, which remains within acceptable operating parameters for this frequency and load capacitance combination.

Q: What is the significance of ESR variation among the substitute parts?

A: ESR (Equivalent Series Resistance) affects crystal oscillator circuit performance, including startup characteristics and power consumption. The main part specifies 40 Ohms. The H130B-27.000-20-F-TR provides lower ESR (20 Ohms), potentially improving startup margin. The 7M-27.000MBBK-T provides higher ESR (60 Ohms), which may increase startup time but remains within acceptable limits for 27 MHz fundamental mode operation. Circuit simulation or prototype testing is appropriate when ESR variation exceeds ±50% of the original specification.

Q: Are packaging format differences (Cut Tape versus Tape & Reel) significant for substitution?

A: Packaging format differences do not affect electrical or mechanical compatibility. Cut Tape (CT) & Digi-Reel® and Tape & Reel (TR) formats represent different procurement and handling methods. Selection between formats depends on production volume, automated assembly equipment compatibility, and inventory management practices. All formats deliver identical component specifications.

Q: Which substitute part is recommended for new design implementation?

A: Selection depends on specific application constraints. The ECS-270-20-33-TR offers highest inventory availability and current ROHS3 compliance. The H130B-27.000-20-F-TR provides lowest ESR (20 Ohms) and maintains footprint compatibility with the original 7B-27.000MBBK-T. The 7M-27.000MBBK-T offers TXC CORPORATION continuity with reduced footprint. All three parts meet the electrical and mechanical requirements for direct substitution.

Q: Do all substitute parts maintain the same operating temperature range?

A: Yes. All substitute parts operate across the identical temperature range of -20°C to 70°C, matching the main part specification. No thermal performance adjustment is required during substitution.

Q: What is the MSL (Moisture Sensitivity Level) requirement for these crystals?

A: All parts, including the main component and all substitutes, are classified as MSL 1 (Unlimited). This classification indicates no moisture sensitivity and no special storage or handling requirements. Standard industrial storage conditions are appropriate for all variants.