Equivalent & Substitute Parts for 7B-40.000MBBK-T

Part Overview

The 7B-40.000MBBK-T is a 40 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 40 MHz with ±50ppm frequency stability and 20pF load capacitance. The product is classified as Obsolete, making identification of equivalent and substitute parts essential for ongoing design support and procurement continuity. Substitute parts maintain identical electrical specifications while offering improved availability and active product status.

Substiute Parts

7B-40.000MBBK-T

TXC CORPORATIONIn Stock: 7667B-40.000MBBK-T Datasheet

Current PartRFQ

7M-40.000MBBK-T

TXC CORPORATIONIn Stock: 9267M-40.000MBBK-T Datasheet

SimilarRFQ

ECS-400-20-33-TR

ECS Inc.In Stock: 1795ECS-400-20-33-TR Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 7B-40.000MBBK-T is determined by strict equivalence across the following critical parameters:

Mandatory Matching Parameters:

• Frequency: 40.0000 MHz
• Frequency Stability: ±50ppm
• Load Capacitance: 20pF
• Operating Mode: Fundamental
• Package Type: 4-SMD, No Lead
• Operating Temperature Range: -20°C to 70°C
• Mounting Type: Surface Mount
• RoHS Compliance: Required

Allowable Variations:

• ESR (Equivalent Series Resistance): 40 Ohms to 60 Ohms
• Physical dimensions: Variations permitted within SMD package constraints
• Packaging format: Bulk or Tape & Reel acceptable
• Manufacturer: Different manufacturers permitted if all electrical parameters match

Two substitute parts meet these criteria: the 7M-40.000MBBK-T (TXC CORPORATION, active product) and the ECS-400-20-33-TR (ECS Inc., active product). Both maintain identical frequency, stability, load capacitance, and temperature specifications while differing only in ESR and physical footprint dimensions.

Parameter Comparison

Engineering Selection Recommendations

Primary Substitute: 7M-40.000MBBK-T

The 7M-40.000MBBK-T is the preferred substitute for the obsolete 7B-40.000MBBK-T. Both parts are manufactured by TXC CORPORATION and maintain identical electrical specifications across all critical parameters. The 7M series represents the active product line continuation, with 901 units currently in stock. The ESR difference (60 Ohms versus 40 Ohms) falls within acceptable tolerance for most circuit applications. The reduced physical dimensions (3.20mm x 2.50mm versus 5.00mm x 3.20mm) and lower profile (0.80mm versus 1.05mm) provide improved PCB layout flexibility. Tape & Reel packaging supports automated assembly processes.

Secondary Substitute: ECS-400-20-33-TR

The ECS-400-20-33-TR manufactured by ECS Inc. provides an alternative from a different supplier while maintaining identical electrical performance. This part matches the original ESR specification at 40 Ohms and offers the highest inventory availability (1767 units in stock). ROHS3 compliance exceeds the RoHS Compliant status of the original part. Physical dimensions and height match the 7M-40.000MBBK-T. Selection of this part is appropriate when supplier diversification or extended inventory assurance is required.

Substitution Constraints:

PCB layout modifications are required when substituting the 7B-40.000MBBK-T with either the 7M-40.000MBBK-T or ECS-400-20-33-TR due to reduced footprint dimensions. The original part measures 5.00mm x 3.20mm; both substitutes measure 3.20mm x 2.50mm. Verify PCB pad spacing and component placement clearances before implementation. All three parts operate within the identical -20°C to 70°C temperature range and maintain MSL 1 (Unlimited) moisture sensitivity classification.

Frequently Asked Questions (FAQ)

Q: Can the 7M-40.000MBBK-T be used as a direct replacement for the 7B-40.000MBBK-T without circuit modifications?

A: Electrical substitution is direct; all frequency, stability, load capacitance, and temperature specifications are identical. However, physical footprint differs (3.20mm x 2.50mm versus 5.00mm x 3.20mm), requiring PCB layout modifications. Verify pad spacing and component placement clearances before assembly.

Q: What is the significance of the ESR difference between the 7B-40.000MBBK-T (40 Ohms) and 7M-40.000MBBK-T (60 Ohms)?

A: ESR affects circuit startup characteristics and power consumption in oscillator circuits. The 20 Ohm difference is within typical design margins for 40 MHz fundamental mode crystals. Verify oscillator circuit design specifications to confirm compatibility. Most standard oscillator ICs accommodate this ESR range.

Q: Why are the 7M-40.000MBBK-T and ECS-400-20-33-TR smaller than the original 7B-40.000MBBK-T?

A: The 7B series represents an older product generation with larger SMD packaging. The 7M and ECS-400 series utilize modern miniaturized 4-SMD, No Lead package technology, reducing footprint from 5.00mm x 3.20mm to 3.20mm x 2.50mm while maintaining identical electrical performance.

Q: Are all three parts RoHS compliant?

A: Yes. The 7B-40.000MBBK-T and 7M-40.000MBBK-T carry RoHS Compliant certification. The ECS-400-20-33-TR carries ROHS3 Compliant certification, which represents an enhanced compliance standard. All three parts are suitable for RoHS-regulated applications.

Q: What packaging formats are available for these parts?

A: The 7B-40.000MBBK-T is supplied in Bulk packaging. Both the 7M-40.000MBBK-T and ECS-400-20-33-TR are supplied in Tape & Reel (TR) format, which is standard for automated PCB assembly processes. Tape & Reel packaging provides improved handling and placement accuracy.

Q: Which substitute part should be selected for new designs?

A: For new designs, either the 7M-40.000MBBK-T or ECS-400-20-33-TR is appropriate, as both are active products with established supply chains. The 7M-40.000MBBK-T maintains TXC CORPORATION manufacturer continuity. The ECS-400-20-33-TR provides supplier diversification and higher inventory availability (1767 units versus 901 units).

Q: Is the Moisture Sensitivity Level identical across all three parts?

A: Yes. All three parts carry MSL 1 (Unlimited) classification, indicating unlimited shelf life under standard storage conditions without baking requirements prior to assembly.