ISL6439IBZ Equivalent & Substitute Parts

Part Overview

The ISL6439IBZ is a buck regulator positive output step-down DC-DC controller IC manufactured by Renesas Electronics Corporation in a 14-SOIC package. This device functions as a transistor driver for single-output, single-phase buck topology applications with a switching frequency of 300kHz and 100% maximum duty cycle. The part is classified as obsolete, making identification of equivalent and substitute components essential for ongoing design support and production continuity.

Substiute Parts

ISL6439IBZ

Renesas Electronics CorporationIn Stock: 2343ISL6439IBZ Datasheet

Current PartRFQ

ISL6439AIBZ

IntersilIn Stock: 4737ISL6439AIBZ Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the ISL6439IBZ is determined by strict alignment of the following critical parameters:

Mandatory Matching Parameters:

• Package / Case: 14-SOIC (0.154", 3.90mm Width)
• Function: Step-Down
• Output Configuration: Positive
• Topology: Buck
• Number of Outputs: 1
• Output Phases: 1
• Voltage - Supply (Vcc/Vdd): 2.97V ~ 3.63V
• Duty Cycle (Max): 100%
• Synchronous Rectifier: Yes
• Output Type: Transistor Driver
• Control Features: Enable, Phase Control
• Operating Temperature: -40°C ~ 85°C (TA)
• Mounting Type: Surface Mount

Allowable Variation Parameters:

• Frequency - Switching: May vary within design tolerance
• Manufacturer: Different manufacturer acceptable if all mandatory parameters align
• Product Status: Active status preferred for long-term availability

The ISL6439AIBZ qualifies as a parametric equivalent based on full alignment with all mandatory parameters.

Parameter Comparison

Engineering Selection Recommendations

The ISL6439AIBZ is a direct parametric equivalent to the ISL6439IBZ. Both devices share identical electrical specifications, package form factor, and functional characteristics across all critical parameters. The primary distinction is product status: the ISL6439IBZ is obsolete while the ISL6439AIBZ is active, providing superior long-term availability and supply chain continuity.

The ISL6439AIBZ operates at 600kHz switching frequency compared to the ISL6439IBZ at 300kHz. This higher frequency does not affect functional compatibility within the specified electrical and thermal operating ranges, as both devices maintain identical supply voltage, duty cycle, and temperature specifications.

For new designs or production continuity of existing designs, the ISL6439AIBZ is the appropriate selection due to its active product status and equivalent performance characteristics.

Frequently Asked Questions (FAQ)

Q: Can the ISL6439AIBZ directly replace the ISL6439IBZ in existing designs?

A: Yes. The ISL6439AIBZ is a parametric equivalent with identical package, electrical specifications, and functional characteristics. Direct pin-for-pin substitution is supported.

Q: What is the significance of the different switching frequencies (300kHz vs 600kHz)?

A: Both devices operate within the same supply voltage range (2.97V ~ 3.63V) and maintain 100% maximum duty cycle. The higher switching frequency of the ISL6439AIBZ does not affect functional compatibility or electrical performance within the specified operating parameters.

Q: Why is the ISL6439IBZ classified as obsolete?

A: Obsolete status indicates the part is no longer in active production. The ISL6439AIBZ provides equivalent functionality with active product status, ensuring ongoing availability and support.

Q: Are there any compliance differences between these parts?

A: The ISL6439IBZ carries ROHS3 compliance certification. The ISL6439AIBZ lists RoHS status as not applicable. Both devices maintain identical REACH and ECCN classifications. Compliance requirements should be evaluated against specific application and regional standards.

Q: Is the 14-SOIC package identical between both parts?

A: Yes. Both devices use the 14-SOIC package with 0.154" width (3.90mm). Package dimensions, pin configuration, and mounting type are identical, supporting direct PCB-level substitution.

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

A: Both the ISL6439IBZ and ISL6439AIBZ carry MSL 3 rating with a 168-hour floor life. Identical moisture handling and storage requirements apply to both devices.