B39921R2706U310 Equivalent & Substitute Parts

Part Overview

The B39921R2706U310 is a 915MHz Surface Acoustic Wave (SAW) filter manufactured by Qualcomm for RF front-end (RFFE) applications. This component operates as a resonant filter element with 7dB insertion loss in an 8-SMD, No Lead surface mount package. The part is classified as obsolete, necessitating identification of active equivalent components for ongoing design support and procurement continuity.

Substiute Parts

B39921R2706U310

Qualcomm (RF front-end (RFFE) filters)In Stock: 783B39921R2706U310 Datasheet

Current PartRFQ

B39921R2906H110

Qualcomm (RF front-end (RFFE) filters)In Stock: 884B39921R2906H110 Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the B39921R2706U310 is based on the following critical parameters:

Frequency Alignment: Both the main part and substitute operate at 915 MHz, the primary functional requirement for RF filtering applications in this frequency band.

Manufacturer Consistency: Both components are manufactured by Qualcomm within the B39921 series, ensuring design lineage and compatibility with existing RF front-end architectures.

Surface Mount Technology: Both parts utilize surface mount construction, maintaining compatibility with standard PCB assembly processes and equipment.

Compliance Standards: Both components meet ROHS3 compliance and REACH unaffected status, satisfying regulatory requirements for electronic component procurement.

Active Product Status: The substitute part B39921R2906H110 maintains active product status, providing long-term availability and supply chain stability compared to the obsolete main part.

Parameter Comparison

Engineering Selection Recommendations

For Direct Substitution: The B39921R2906H110 serves as the active equivalent for the obsolete B39921R2706U310. Both components share the same 915 MHz center frequency, Qualcomm manufacturer origin, and B39921 series designation. The substitute maintains ROHS3 compliance and REACH unaffected status, satisfying regulatory requirements identical to the main part.

Package Consideration: The substitute employs a smaller 6-SMD, No Lead package (3.00mm x 3.00mm) compared to the main part's 8-SMD, No Lead package (5.00mm x 5.00mm). This dimensional difference requires PCB layout verification to confirm footprint compatibility with existing designs.

Moisture Handling: The substitute operates under MSL 3 (168 Hours) conditions, compared to the main part's MSL 1 (Unlimited). This requires adherence to moisture control protocols during storage, handling, and assembly processes.

Component Classification: The main part functions as a SAW filter, while the substitute is classified as a SAW resonator without capacitor. This functional distinction requires circuit-level analysis to confirm performance equivalence within the target application.

Frequently Asked Questions (FAQ)

Q: Can B39921R2906H110 directly replace B39921R2706U310 in existing designs?

A: Both components operate at 915 MHz and share Qualcomm B39921 series lineage. However, the substitute's smaller package footprint (3.00mm x 3.00mm versus 5.00mm x 5.00mm) and different component classification (resonator versus filter) require PCB layout and circuit verification before implementation.

Q: What is the significance of the package size difference?

A: The substitute's 6-SMD, No Lead package is physically smaller than the main part's 8-SMD, No Lead package. This reduction in footprint may provide space savings but requires confirmation that the PCB layout accommodates the new pad configuration and component placement.

Q: How does the MSL rating difference affect component handling?

A: The main part operates under MSL 1 (Unlimited), allowing indefinite storage without moisture control. The substitute operates under MSL 3 (168 Hours), requiring moisture control measures during storage and assembly. Components must be baked according to IPC standards if moisture absorption exceeds specified limits.

Q: Are both components compliant with current regulatory standards?

A: Both components are ROHS3 compliant and REACH unaffected, meeting current regulatory requirements for electronic component procurement and use in regulated markets.

Q: What is the functional difference between a SAW filter and a SAW resonator?

A: The main part is classified as a SAW filter with specified 7dB insertion loss. The substitute is classified as a SAW resonator without capacitor. These classifications indicate different circuit topologies and performance characteristics. Circuit-level analysis is required to confirm functional equivalence.

Q: Is the substitute part actively manufactured?

A: Yes, B39921R2906H110 maintains active product status, ensuring ongoing availability and supply chain continuity compared to the obsolete main part.