MIC4575-3.3BU TR Equivalent & Substitute Parts

Part Overview

The MIC4575-3.3BU TR is a Buck/Buck-Boost Switching Regulator IC from Microchip Technology, delivering fixed 3.3V output at 1.7A (Switch) in a TO-263-6 package. This part is classified as Obsolete, making substitute components necessary for new designs and ongoing production requirements. The device supports input voltage ranges from 4V to 24V with a switching frequency of 200kHz and operates across -40°C to 85°C.

Substiute Parts

MIC4575-3.3BU TR

Microchip TechnologyIn Stock: 941MIC4575-3.3BU TR Datasheet

Current PartRFQ

MIC4575-3.3WU-TR

Microchip TechnologyIn Stock: 707MIC4575-3.3WU-TR 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

Substitute parts for the MIC4575-3.3BU TR are selected based on the following critical parameters that determine functional compatibility:

Primary Substitution Criteria:

• Output voltage: 3.3V fixed
• Package type: TO-263-6, D2PAK (5 Leads + Tab)
• Mounting type: Surface Mount
• Output configuration: Positive
• Number of outputs: 1
• Output type: Fixed

Secondary Compatibility Parameters:

• Input voltage range (minimum 4V support required)
• Output current capability (minimum 1A required)
• Operating temperature range (-40°C minimum, 85°C minimum)
• Synchronous rectifier: No

The substitute parts listed below maintain these core electrical and mechanical specifications while offering improved product status and compliance characteristics.

Parameter Comparison

Engineering Selection Recommendations

MIC4575-3.3WU-TR (Microchip Technology) This part provides the closest electrical match to the MIC4575-3.3BU TR, maintaining identical output current (1.7A), input voltage range (4V to 24V), switching frequency (200kHz), and topology (Buck/Buck-Boost). The primary advantage is Active product status and ROHS3 compliance, addressing the obsolescence and regulatory concerns of the original part. This is the preferred direct substitute when Microchip sourcing is required.

LM2591HVS-3.3/NOPB and LM2591HVSX-3.3/NOPB (Texas Instruments) These Texas Instruments SIMPLE SWITCHER® devices offer extended input voltage capability (up to 60V) and wider operating temperature range (-40°C to 125°C). Output current is reduced to 1A, which is a design consideration for applications requiring the full 1.7A capability. Both parts are Active with ROHS3 compliance. The LM2591HVSX-3.3/NOPB variant offers higher inventory availability (2314 pcs).

TL2575-33IKTTR and TL2575HV-33IKTTR (Texas Instruments) These parts feature lower switching frequency (52kHz) compared to the original 200kHz, which may impact PCB layout and filtering requirements. The TL2575HV-33IKTTR supports higher maximum input voltage (60V) versus TL2575-33IKTTR (40V). Both maintain 1A output current and are Active with ROHS3 compliance. These options are suitable for applications where lower switching frequency is acceptable or beneficial.

Frequently Asked Questions (FAQ)

Q: Can I use a substitute part with lower output current (1A instead of 1.7A)? A: Substitution with lower output current is only valid if your application's maximum current draw does not exceed 1A. If your design requires the full 1.7A capability, only MIC4575-3.3WU-TR maintains this specification. For applications drawing less than 1A, Texas Instruments alternatives are suitable.

Q: What is the impact of different switching frequencies on my design? A: The original MIC4575-3.3BU TR operates at 200kHz. Substitute parts operate at 150kHz (LM2591 series) or 52kHz (TL2575 series). Lower switching frequencies require larger output filter components and may affect EMI characteristics. PCB layout and component selection should be re-evaluated when switching frequency changes.

Q: Are all substitute parts pin-compatible with the original MIC4575-3.3BU TR? A: All listed substitutes use the same TO-263-6 D2PAK package with 5 leads plus tab. However, pin functionality may differ between Buck-only topologies (Texas Instruments parts) and Buck/Buck-Boost topologies (Microchip parts). Verify schematic compatibility before PCB layout changes.

Q: Why do some substitutes support higher input voltages (60V vs 24V)? A: Texas Instruments LM2591 and TL2575HV parts are designed for wider input voltage applications. If your design operates within the original 4V to 24V range, the extended voltage capability of these parts does not affect compatibility but provides additional design margin.

Q: What is the difference between MIC4575-3.3WU-TR and MIC4575-3.3BU TR? A: Both parts are functionally identical with matching electrical specifications. The primary difference is product status: MIC4575-3.3BU TR is Obsolete while MIC4575-3.3WU-TR is Active. The WU variant also carries ROHS3 compliance versus non-compliance of the BU variant.

Q: Can I substitute a Buck-only topology (Texas Instruments) for a Buck/Buck-Boost topology (Microchip)? A: Substitution is valid only if your application requires Step-Down (Buck) operation exclusively. If your design utilizes Step-Up or Step-Up/Step-Down capability, only MIC4575-3.3WU-TR maintains full functional compatibility. Review your input voltage source and output requirements before selecting a Buck-only alternative.

Q: What are the compliance and regulatory differences between these parts? A: The original MIC4575-3.3BU TR is RoHS non-compliant. All substitute parts listed are ROHS3 compliant. For REACH status, LM2591HVS-3.3/NOPB is REACH Affected, while all other substitutes are REACH Unaffected. Verify your regulatory requirements before final part selection.