AP131-33WL-7 Equivalent & Substitute Parts

Part Overview

The AP131-33WL-7 is a linear voltage regulator IC from Diodes Incorporated designed to deliver a fixed 3.3V output at 300mA in a compact SOT-25 package. This component is classified as obsolete, making equivalent and substitute parts necessary for ongoing design support and production continuity. The part provides positive fixed output regulation with integrated over-current and over-temperature protection, suitable for low-power applications requiring stable 3.3V rails.

Substiute Parts

AP131-33WL-7

Diodes IncorporatedIn Stock: 22742AP131-33WL-7 Datasheet

Current PartRFQ

AP7331-33WG-7

Diodes IncorporatedIn Stock: 15775AP7331-33WG-7 Datasheet

DirectRFQ

AP139-33WG-7

Diodes IncorporatedIn Stock: 8542AP139-33WG-7 Datasheet

MFR RecommendedRFQ

TPS73233MDBVREP

Texas InstrumentsIn Stock: 888957TPS73233MDBVREP Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the AP131-33WL-7 is determined by the following critical parameters:

• Fixed output voltage of 3.3V
• Output current capability of 300mA or greater
• Maximum input voltage of 5.5V or higher
• Surface mount packaging in SOT-25 or compatible footprint
• Positive fixed output configuration with single regulator
• Over-current and over-temperature protection features
• Operating temperature range of -40°C to 85°C or wider
• RoHS3 compliance

Three substitute parts meet these criteria with varying performance characteristics and product status classifications.

Parameter Comparison

Engineering Selection Recommendations

AP7331-33WG-7 is a direct functional equivalent with active product status. This Diodes Incorporated part maintains identical output voltage and current specifications while offering improved input voltage tolerance (6V maximum) and lower quiescent current (75 µA). The part is currently in active production with unlimited moisture sensitivity rating, making it suitable for immediate design adoption.

AP139-33WG-7 is a manufacturer-recommended substitute from Diodes Incorporated with enhanced performance characteristics. It provides superior dropout voltage performance (0.45V @ 300mA) and lower quiescent current (60 µA), along with additional short-circuit protection. However, this part carries Last Time Buy status and has a moisture sensitivity level of 3 (168 hours), requiring controlled storage conditions. This option is appropriate for designs where performance optimization justifies extended lead time considerations.

TPS73233MDBVREP is an alternative from Texas Instruments with active product status. While this part meets the 3.3V output and core protection requirements, it delivers 250mA output current (50mA less than the main part) and operates with a significantly higher quiescent current (550 µA). The part offers superior dropout voltage (0.15V @ 250mA) and an extended operating temperature range (-55°C to 125°C). The supplier device package differs (SOT-23-5 versus SOT-25), requiring PCB layout modification. This option is suitable only for applications where 250mA output current is sufficient and the extended temperature range provides design value.

Frequently Asked Questions (FAQ)

Q: Can AP7331-33WG-7 be used as a direct replacement for AP131-33WL-7?

A: Yes. Both parts deliver 3.3V at 300mA in identical SOT-25 packaging with matching pinout. The AP7331-33WG-7 is electrically compatible and offers improved specifications including higher input voltage tolerance (6V vs 5.5V) and lower quiescent current (75 µA vs 100 µA). Active product status ensures ongoing availability.

Q: What are the key differences between AP139-33WG-7 and AP7331-33WG-7?

A: Both are Diodes Incorporated parts with identical output specifications. AP139-33WG-7 provides superior dropout voltage (0.45V vs 0.55V) and lower quiescent current (60 µA vs 75 µA), plus short-circuit protection. However, AP139-33WG-7 is Last Time Buy with moisture sensitivity level 3, while AP7331-33WG-7 is active production with MSL 1.

Q: Is TPS73233MDBVREP suitable for all applications using AP131-33WL-7?

A: No. TPS73233MDBVREP delivers only 250mA output current versus the required 300mA. Applications requiring the full 300mA output current cannot use this part. Additionally, the SOT-23-5 package differs from SOT-25, requiring PCB redesign. This part is suitable only for designs where 250mA output current is adequate.

Q: What packaging considerations apply to these substitutes?

A: AP7331-33WG-7 and AP139-33WG-7 use identical SOT-25 packaging (SC-74A, SOT-753) with matching pinout to AP131-33WL-7, enabling direct PCB substitution. TPS73233MDBVREP uses SOT-23-5 packaging, which has different pin configuration and requires PCB layout modification.

Q: Which substitute offers the best long-term availability?

A: AP7331-33WG-7 is the optimal choice for long-term availability. It maintains active product status with unlimited moisture sensitivity rating and is currently in production with substantial inventory levels.