BF245B_D74Z Equivalent & Substitute Parts

Part Overview

The BF245B_D74Z is an RF MOSFET JFET manufactured by onsemi, designed for RF applications in a through-hole TO-92-3 package. This device operates at a rated voltage of 30V with a maximum current rating of 15mA. The BF245B_D74Z is classified as obsolete, making equivalent and substitute parts necessary for ongoing design support and procurement.

Substiute Parts

BF245B_D74Z

onsemiIn Stock: 899BF245B_D74Z Datasheet

Current PartRFQ

MMBF5485

onsemiIn Stock: 65234MMBF5485 Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the BF245B_D74Z is determined by the following critical parameters:

Technology & Configuration: Both the main part and substitute must be N-Channel JFET devices to maintain functional equivalence in RF applications.

Voltage Rating: The substitute must support the operating voltage requirements of the original circuit. The BF245B_D74Z operates at 30V rated voltage.

Current Handling: The substitute must accommodate the current demands of the application. The BF245B_D74Z is rated for 15mA maximum current.

Package Compatibility: The BF245B_D74Z uses a through-hole TO-92-3 package. Substitutes may use alternative packages (such as surface-mount SOT-23-3) if the circuit design permits package conversion.

Regulatory Compliance: Both parts must maintain equivalent REACH and ECCN classifications to ensure compliance with applicable regulations.

The MMBF5485 is identified as a substitute part. While it operates at a lower rated voltage (25V) and reduced current rating (10mA), it maintains the same N-Channel JFET technology and onsemi manufacturer origin. The MMBF5485 is an active product with current availability, addressing the obsolescence of the BF245B_D74Z.

Parameter Comparison

Engineering Selection Recommendations

Product Status Consideration: The BF245B_D74Z is classified as obsolete. The MMBF5485 is an active product with substantial inventory availability (65,200 pieces), providing long-term procurement security and design continuity.

Compliance & Certifications: Both parts maintain identical REACH and ECCN classifications (REACH Unaffected, EAR99), ensuring regulatory equivalence. The MMBF5485 carries RoHS3 compliance, providing additional environmental compliance assurance.

Electrical Parameter Alignment: The MMBF5485 operates within reduced voltage and current specifications compared to the BF245B_D74Z. Circuit designs operating at or below 25V with current demands not exceeding 10mA are suitable for direct substitution. Designs requiring the full 30V rating or 15mA current capacity require circuit redesign or alternative substitute evaluation.

Package Transition: The MMBF5485 uses a surface-mount SOT-23-3 package, whereas the BF245B_D74Z uses through-hole TO-92-3. This substitution requires PCB layout modification and assembly process changes.

Frequently Asked Questions (FAQ)

Q: Can the MMBF5485 directly replace the BF245B_D74Z in all applications?

A: Direct substitution is limited by electrical parameters. The MMBF5485 is rated for 25V maximum (versus 30V for the BF245B_D74Z) and 10mA maximum current (versus 15mA). Substitution is valid only for circuits operating within these reduced specifications. Additionally, the package change from through-hole to surface-mount requires PCB redesign.

Q: What are the key differences between these two parts?

A: Both are N-Channel JFET devices from onsemi with identical technology and regulatory compliance. Primary differences include: voltage rating (30V vs. 25V), current rating (15mA vs. 10mA), package type (through-hole TO-92-3 vs. surface-mount SOT-23-3), product status (obsolete vs. active), and the MMBF5485 provides specified frequency (400MHz) and noise figure (4dB) characteristics.

Q: Is the MMBF5485 suitable for RF applications?

A: Yes. The MMBF5485 is specified for RF applications with a 400MHz frequency rating and 4dB noise figure. The BF245B_D74Z does not provide frequency or noise figure specifications in the available data.

Q: What compliance certifications apply to both parts?

A: Both parts are REACH Unaffected and classified as EAR99 for export control purposes. The MMBF5485 additionally carries RoHS3 compliance certification.

Q: Does the package change affect circuit performance?

A: Package change from through-hole TO-92-3 to surface-mount SOT-23-3 requires PCB layout modification and different assembly processes. Electrical performance characteristics remain equivalent within the specified parameter ranges. Lead inductance and parasitic characteristics may differ slightly due to package geometry.

Q: What is the moisture sensitivity level for both parts?

A: Both the BF245B_D74Z and MMBF5485 carry MSL 1 (Unlimited) classification, indicating no moisture sensitivity restrictions during storage or handling.