MIC79050-4.2BS TR Equivalent & Substitute Parts

Part Overview

The MIC79050-4.2BS TR is a single-cell lithium-ion battery charger IC in SOT-223-3 surface mount packaging, manufactured by Microchip Technology. This device provides constant and pulsed charging current control with integrated fault protection including over-current, over-temperature, reverse battery, and reverse current protection. The part is classified as obsolete, making identification of compatible substitutes essential for ongoing design support and production continuity.

Substiute Parts

MIC79050-4.2BS TR

Microchip TechnologyIn Stock: 1104MIC79050-4.2BS TR Datasheet

Current PartRFQ

MIC79050-4.2YS-TR

Microchip TechnologyIn Stock: 904MIC79050-4.2YS-TR Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the MIC79050-4.2BS TR is determined by the following critical parameters:

• Battery Chemistry & Cell Count: Both parts must support single-cell lithium-ion charging
• Battery Pack Voltage: Charge termination voltage must be 4.2V
• Supply Voltage Range: Maximum supply voltage of 16V or greater
• Charging Current Mode: Support for constant and pulsed charging current
• Fault Protection Features: Over-current, over-temperature, reverse battery, and reverse current protection must be present
• Operating Temperature Range: -40°C to 125°C junction temperature
• Package Compatibility: SOT-223-3 surface mount package with TO-261-4 or TO-261AA case designation

The MIC79050-4.2YS-TR meets all these criteria and is classified as a direct substitute.

Parameter Comparison

Engineering Selection Recommendations

The MIC79050-4.2YS-TR is the direct substitute for the obsolete MIC79050-4.2BS TR. Both parts share identical electrical specifications and package designations, ensuring functional compatibility in existing designs.

The primary distinction between these parts is product lifecycle status and regulatory compliance:

• Product Status: The MIC79050-4.2YS-TR is active and available for new designs, whereas the MIC79050-4.2BS TR is obsolete
• RoHS Compliance: The substitute part is ROHS3 compliant, meeting current environmental regulations
• Moisture Sensitivity: The substitute part has MSL 3 (168 hours) compared to MSL 1 (unlimited) for the original part, requiring appropriate handling during storage and assembly

For applications requiring the MIC79050-4.2BS TR, transition to the MIC79050-4.2YS-TR is recommended to ensure long-term supply availability and regulatory compliance.

Frequently Asked Questions (FAQ)

Q: Are the MIC79050-4.2BS TR and MIC79050-4.2YS-TR electrically identical?

A: Yes. Both parts provide identical charging functionality for single-cell lithium-ion batteries at 4.2V termination voltage, with the same fault protection features, operating temperature range, and supply voltage specifications.

Q: What is the difference between these two parts?

A: The primary differences are product status (obsolete vs. active), RoHS compliance (non-compliant vs. ROHS3 compliant), and moisture sensitivity level (MSL 1 vs. MSL 3). Electrical and functional specifications are identical.

Q: Can I use the MIC79050-4.2YS-TR as a direct replacement in existing designs?

A: Yes. The substitute part is pin-compatible and functionally equivalent. The SOT-223-3 package and TO-261-4/TO-261AA case designations are identical, allowing direct PCB substitution.

Q: What does MSL 3 (168 hours) mean for the substitute part?

A: Moisture Sensitivity Level 3 indicates the part must be stored in controlled humidity conditions and used within 168 hours of opening the moisture barrier bag. Proper handling procedures must be followed during storage and assembly to prevent moisture absorption.

Q: Is the substitute part suitable for new product designs?

A: Yes. The MIC79050-4.2YS-TR is the recommended choice for new designs due to its active product status and ROHS3 compliance.