MIC4575-3.3BU Equivalent & Substitute Parts

Part Overview

The MIC4575-3.3BU is a Buck/Buck-Boost Switching Regulator IC manufactured by Microchip Technology, delivering a fixed 3.3V output at 1.7A (Switch) in a TO-263-6 package. This part is classified as Obsolete, which necessitates identification of functionally equivalent alternatives for new designs and ongoing production requirements. Substitute parts must maintain electrical compatibility across input voltage range, output voltage specification, and package form factor while meeting current RoHS and REACH compliance standards.

Substiute Parts

MIC4575-3.3BU

Microchip TechnologyIn Stock: 8696MIC4575-3.3BU Datasheet

Current PartRFQ

MIC4575-3.3WU

Microchip TechnologyIn Stock: 4000MIC4575-3.3WU Datasheet

DirectRFQ

LM2591HVS-3.3/NOPB

Texas InstrumentsIn Stock: 1121LM2591HVS-3.3/NOPB Datasheet

MFR RecommendedRFQ

LM2591HVSX-3.3/NOPB

Texas InstrumentsIn Stock: 2369LM2591HVSX-3.3/NOPB Datasheet

MFR RecommendedRFQ

TL2575-33IKTTR

Texas InstrumentsIn Stock: 3717TL2575-33IKTTR Datasheet

MFR RecommendedRFQ

TL2575HV-33IKTTR

Texas InstrumentsIn Stock: 1809TL2575HV-33IKTTR Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution logic is based on the following critical parameters that determine functional equivalence:

1. Output Voltage: All substitutes must deliver fixed 3.3V output
2. Package Form Factor: All substitutes must use TO-263-6 (D2PAK) package for PCB compatibility
3. Input Voltage Range: Substitutes must accommodate the minimum 4V input requirement of the original design
4. Output Current Capability: Substitutes rated at 1A or higher satisfy the 1.7A requirement through design margin or direct equivalence
5. Mounting Type: Surface Mount compatibility required
6. Compliance Status: Active product status and RoHS3 compliance preferred for new designs

The MIC4575-3.3WU represents a direct Microchip equivalent with identical electrical specifications and active product status. Texas Instruments alternatives (LM2591HVS-3.3/NOPB, LM2591HVSX-3.3/NOPB, TL2575-33IKTTR, TL2575HV-33IKTTR) provide Buck topology regulation with compatible packaging and compliance certifications, though with reduced output current ratings (1A) and modified input voltage ranges.

Parameter Comparison

Engineering Selection Recommendations

Primary Substitute: MIC4575-3.3WU

The MIC4575-3.3WU is the direct equivalent replacement for the MIC4575-3.3BU. It maintains identical electrical specifications (1.7A output current, 200kHz switching frequency, 4V to 24V input range) and package form factor. The MIC4575-3.3WU carries Active product status and ROHS3 compliance, making it the preferred choice for new designs and production continuity.

Secondary Substitutes: Texas Instruments LM2591 and TL2575 Series

The LM2591HVS-3.3/NOPB and LM2591HVSX-3.3/NOPB provide Buck regulation with 1A output current and extended input voltage range (4.5V to 60V). These parts are suitable for applications where the 1.7A output current of the original design can be accommodated by 1A capability through circuit design margin or reduced load requirements.

The TL2575-33IKTTR and TL2575HV-33IKTTR offer similar Buck topology with 1A output current and lower switching frequency (52kHz). The TL2575HV-33IKTTR extends the maximum input voltage to 60V, providing broader input range compatibility.

All Texas Instruments alternatives carry Active product status and ROHS3 compliance. Selection between LM2591 and TL2575 variants depends on input voltage range requirements and switching frequency constraints in the target application.

Frequently Asked Questions (FAQ)

Q: Can the MIC4575-3.3WU directly replace the MIC4575-3.3BU without circuit modification?

A: Yes. The MIC4575-3.3WU is electrically and mechanically identical to the MIC4575-3.3BU. No circuit modifications are required. The primary difference is product status (Active vs. Obsolete) and RoHS compliance (ROHS3 vs. non-compliant).

Q: Why do Texas Instruments substitutes have lower output current ratings (1A vs. 1.7A)?

A: The LM2591 and TL2575 series are designed with different output current specifications. Applications requiring the full 1.7A capability should prioritize the MIC4575-3.3WU. Applications with reduced current requirements (≤1A) can use Texas Instruments alternatives.

Q: Are the Texas Instruments parts pin-compatible with the MIC4575-3.3BU?

A: All substitute parts use the TO-263-6 (D2PAK) package with identical pinout. Pin compatibility is maintained across all listed substitutes.

Q: What is the impact of different switching frequencies (200kHz vs. 150kHz vs. 52kHz)?

A: Switching frequency affects output filter component sizing and EMI characteristics. The MIC4575-3.3WU operates at 200kHz (matching the original). Texas Instruments alternatives operate at lower frequencies (150kHz or 52kHz), which may require filter component recalculation but generally reduce switching losses and EMI.

Q: Can I use a Texas Instruments substitute if my input voltage is below 4.5V?

A: No. The LM2591 and TL2575 series specify minimum input voltages of 4.5V or 4.75V. If your design requires operation at 4V input, the MIC4575-3.3WU is the only suitable substitute.

Q: What is the difference between LM2591HVS-3.3/NOPB and LM2591HVSX-3.3/NOPB?

A: Both parts are electrically identical. The primary difference is packaging format: LM2591HVS-3.3/NOPB is supplied in Tube packaging, while LM2591HVSX-3.3/NOPB is supplied in Cut Tape (CT) & Digi-Reel format. Electrical performance and pin compatibility are identical.

Q: Should I use the TL2575-33IKTTR or TL2575HV-33IKTTR?

A: Both parts operate at 52kHz switching frequency with 1A output current. The TL2575HV-33IKTTR supports higher maximum input voltage (60V vs. 40V). Select based on your application's input voltage range requirements.