FDMF6706B Equivalent & Substitute Parts

Part Overview

The FDMF6706B is a half bridge driver IC designed for synchronous buck converter applications, manufactured by onsemi in the XS™ DrMOS series. This component integrates gate driver and power MOSFET functionality in a 40-PQFN (6x6) surface mount package. The part is currently listed as obsolete, making identification of compatible substitutes essential for ongoing design support and production continuity.

Substiute Parts

FDMF6706B

onsemiIn Stock: 907FDMF6706B Datasheet

Current PartRFQ

FDMF6820B

Fairchild SemiconductorIn Stock: 16015FDMF6820B Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the FDMF6706B is determined by the following critical parameters:

• Output Configuration: Must be Half Bridge
• Package Type: Must be 40-PQFN (6x6) or compatible footprint
• Interface: Must support PWM control
• Technology: Must be DrMOS architecture
• Supply Voltage Range: Must accommodate 4.5V ~ 5.5V
• Load Voltage Range: Must support minimum 3V ~ 15V
• Fault Protection: Must include Over Temperature, Shoot-Through, and UVLO protection
• Mounting Type: Must be Surface Mount

The FDMF6820B meets all substitution criteria. While it offers higher current capability (55A vs. 43A) and extended load voltage range (3V ~ 16V), these represent improvements that maintain backward compatibility with FDMF6706B applications.

Parameter Comparison

Engineering Selection Recommendations

The FDMF6820B is the qualified substitute for FDMF6706B applications based on the following factors:

Product Status: The FDMF6706B is obsolete, while FDMF6820B maintains active manufacturing status, ensuring long-term availability and supply chain continuity.

Electrical Compatibility: Both devices share identical supply voltage (4.5V ~ 5.5V), gate driver interface (PWM), output configuration (Half Bridge), on-resistance characteristics (1Ohm LS/HS), and fault protection mechanisms (Over Temperature, Shoot-Through, UVLO).

Package Compatibility: Both components use 40-PQFN (6x6) surface mount packages with compatible pinouts and footprints suitable for direct PCB substitution.

Performance Enhancement: The FDMF6820B provides higher current capability (55A vs. 43A) and extended load voltage support (3V ~ 16V vs. 3V ~ 15V), representing performance improvements that do not compromise backward compatibility.

Temperature Consideration: The FDMF6706B supports a lower minimum operating temperature (-55°C vs. -40°C). Applications requiring operation below -40°C must retain the original part or identify alternative solutions.

Compliance: Both parts carry identical ECCN (EAR99) and HTSUS (8542.39.0001) classifications, maintaining regulatory consistency.

Frequently Asked Questions (FAQ)

Q: Can FDMF6820B directly replace FDMF6706B on existing PCBs?

A: Yes. Both devices use identical 40-PQFN (6x6) packages with compatible pinouts. No PCB layout modifications are required for footprint compatibility.

Q: What are the key differences between these parts?

A: The FDMF6820B offers higher output current (55A vs. 43A), extended load voltage range (3V ~ 16V vs. 3V ~ 15V), and active product status. The FDMF6706B supports lower minimum operating temperature (-55°C vs. -40°C).

Q: Are there any applications where FDMF6706B cannot be substituted?

A: Applications requiring operation below -40°C junction temperature must use the original FDMF6706B or identify alternative parts with equivalent low-temperature ratings.

Q: Why is FDMF6706B listed as obsolete?

A: Obsolescence typically results from manufacturer product line consolidation or transition to newer technology generations. The FDMF6820B represents the active equivalent within the XS™ DrMOS series.

Q: Do both parts require identical PCB layout considerations?

A: Yes. Both devices use the same package type and thermal characteristics. Existing PCB designs optimized for FDMF6706B remain valid for FDMF6820B without modification.

Q: What is the inventory status for these parts?

A: FDMF6706B has 822 pieces in stock (new original). FDMF6820B has 15,976 pieces in stock, providing significantly greater availability for new designs and production.