MIC4576BU Equivalent & Substitute Parts

Part Overview

The MIC4576BU is a buck switching regulator IC from Microchip Technology designed for positive adjustable output applications. It delivers 3A output current with an adjustable output voltage range from 1.23V to 33V, operating from a 4V to 36V input supply. The device is housed in a TO-263-6 (D2PAK) surface mount package with 5 leads plus tab.

The MIC4576BU is classified as obsolete. Identifying equivalent substitute parts is necessary to maintain design continuity, ensure supply chain reliability, and support ongoing production or maintenance requirements for systems utilizing this regulator.

Substiute Parts

MIC4576BU

Microchip TechnologyIn Stock: 12328MIC4576BU Datasheet

Current PartRFQ

MIC4576WU

Microchip TechnologyIn Stock: 6071MIC4576WU Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the MIC4576BU is determined by strict equivalence across the following critical parameters:

• Topology: Buck (step-down) switching regulator
• Output Configuration: Positive adjustable
• Voltage Specifications: Input 4V–36V, Output 1.23V–33V adjustable
• Current Rating: 3A output
• Switching Frequency: 200kHz
• Package: TO-263-6 (D2PAK, 5 leads + tab)
• Thermal Operating Range: -40°C to 85°C
• Pin Configuration: Identical pinout and functionality

The MIC4576WU meets all these criteria and is therefore a direct functional and pin-compatible substitute for the MIC4576BU.

Parameter Comparison

Engineering Selection Recommendations

The MIC4576WU is the direct substitute for the MIC4576BU. Both devices are manufactured by Microchip Technology and share identical electrical and mechanical specifications across all critical parameters.

The primary distinction between the two parts is product lifecycle status and regulatory compliance. The MIC4576BU is obsolete, while the MIC4576WU maintains active product status. The MIC4576WU is ROHS3 compliant, whereas the MIC4576BU is RoHS non-compliant. For new designs or ongoing production requiring regulatory compliance, the MIC4576WU is the appropriate selection. For legacy system maintenance where RoHS compliance is not a requirement, either part is functionally equivalent.

Frequently Asked Questions (FAQ)

Q: Are the MIC4576BU and MIC4576WU pin-compatible?

A: Yes. Both devices use the TO-263-6 (D2PAK) package with 5 leads plus tab. The pinout and functionality are identical, enabling direct substitution on existing PCB layouts without modification.

Q: What is the difference between the MIC4576BU and MIC4576WU?

A: The devices are electrically and mechanically identical. The primary differences are product status (MIC4576BU is obsolete; MIC4576WU is active) and RoHS compliance (MIC4576BU is non-compliant; MIC4576WU is ROHS3 compliant).

Q: Can I use the MIC4576WU as a direct replacement in my existing design?

A: Yes. The MIC4576WU is a direct functional and pin-compatible substitute. No circuit modifications or PCB changes are required.

Q: What output voltage range does this regulator support?

A: The adjustable output voltage range is 1.23V to 33V, set by external resistor dividers on the feedback network.

Q: What is the maximum input voltage for this device?

A: The maximum input voltage is 36V. The minimum input voltage is 4V.

Q: What is the output current capability?

A: The device delivers a maximum output current of 3A.

Q: What is the switching frequency?

A: The switching frequency is 200kHz.

Q: Is this a synchronous buck regulator?

A: No. The MIC4576BU and MIC4576WU are non-synchronous buck regulators, utilizing an external diode for the freewheeling path.

Q: What is the operating temperature range?

A: The operating temperature range is -40°C to 85°C (ambient temperature, TA).

Q: What packaging options are available?

A: Both the MIC4576BU and MIC4576WU are available in TO-263-6 (D2PAK) surface mount package. The MIC4576WU is supplied in tube packaging.