AP139-18WL-7 Equivalent & Substitute Parts

Part Overview

The AP139-18WL-7 is a linear voltage regulator IC from Diodes Incorporated, designed for positive fixed 1.8V output at 300mA in a SOT-25 surface mount package. This part is classified as Obsolete, making equivalent and substitute parts necessary for ongoing design support and procurement. The device provides regulated 1.8V output with integrated protection features including over-current, over-temperature, and short-circuit protection, suitable for low-power applications requiring stable voltage regulation.

Substiute Parts

AP139-18WL-7

Diodes IncorporatedIn Stock: 6198AP139-18WL-7 Datasheet

Current PartRFQ

AP139-18WG-7

Diodes IncorporatedIn Stock: 3258AP139-18WG-7 Datasheet

Parametric EquivalentRFQ

TPS73218MDBVREP

Texas InstrumentsIn Stock: 841TPS73218MDBVREP Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the AP139-18WL-7 are identified based on the following critical parameters that determine functional compatibility:

• Output voltage: 1.8V fixed
• Output configuration: Positive
• Number of regulators: 1
• Input voltage maximum: 5.5V
• Mounting type: Surface Mount
• Protection features: Over Current, Over Temperature, Short Circuit
• Control features: Enable function

Substitutes are grouped into two categories:

Parametric Equivalent (Same Manufacturer): AP139-18WG-7 maintains identical electrical specifications and output current rating (300mA) with the same manufacturer (Diodes Incorporated), differing only in product status (Last Time Buy) and moisture sensitivity level.

Manufacturer Recommended Alternative: TPS73218MDBVREP from Texas Instruments provides equivalent 1.8V fixed output with reduced output current (250mA) and different package configuration (SOT-23-5), suitable for applications where the lower current rating is acceptable.

Parameter Comparison

Engineering Selection Recommendations

AP139-18WG-7 is the primary substitute for AP139-18WL-7. Both parts are manufactured by Diodes Incorporated with identical electrical specifications and 300mA output current capability. The AP139-18WG-7 maintains full compatibility with existing designs while offering Last Time Buy status, providing a transition path for long-term production requirements. Both parts comply with ROHS3 and maintain equivalent protection and control features.

TPS73218MDBVREP from Texas Instruments serves as an alternative for applications where the reduced output current (250mA versus 300mA) is acceptable. This part offers Active product status, ensuring long-term availability and support. The TPS73218MDBVREP provides an extended operating temperature range (-55°C ~ 125°C) and includes reverse polarity protection. However, the different package configuration (SOT-23-5 versus SOT-25) and higher quiescent current (550 µA versus 60 µA) require circuit board layout modifications and may impact power consumption in battery-powered applications.

Frequently Asked Questions (FAQ)

Q: Can AP139-18WG-7 be used as a direct replacement for AP139-18WL-7?

A: Yes. AP139-18WG-7 is a parametric equivalent with identical output voltage (1.8V), output current (300mA), input voltage rating (5.5V maximum), and protection features. Both use SOT-25 packaging. The primary difference is product status; AP139-18WG-7 is Last Time Buy while AP139-18WL-7 is Obsolete. No circuit modifications are required.

Q: What are the limitations of using TPS73218MDBVREP as a substitute?

A: TPS73218MDBVREP has three key differences: (1) reduced output current rating of 250mA versus 300mA, limiting applications requiring higher current draw; (2) different package configuration (SOT-23-5 versus SOT-25), requiring PCB layout changes; (3) significantly higher quiescent current (550 µA versus 60 µA), which increases standby power consumption. Applications must verify that 250mA output current is sufficient for their requirements.

Q: Are all substitute parts ROHS3 compliant?

A: Yes. AP139-18WL-7, AP139-18WG-7, and TPS73218MDBVREP are all ROHS3 compliant. All three parts are REACH Unaffected and classified under ECCN EAR99.

Q: What is the difference in moisture sensitivity between AP139-18WL-7 and AP139-18WG-7?

A: AP139-18WL-7 has MSL 1 (Unlimited), meaning no moisture sensitivity restrictions. AP139-18WG-7 has MSL 3 (168 Hours), requiring storage in controlled humidity conditions and baking before reflow soldering if exposed to moisture. This affects handling and storage procedures in manufacturing environments.

Q: Does TPS73218MDBVREP offer any advantages over the Diodes Incorporated alternatives?

A: TPS73218MDBVREP offers Active product status, ensuring continued availability and manufacturer support. It provides an extended operating temperature range (-55°C ~ 125°C versus -40°C ~ 85°C) and includes reverse polarity protection. These features are beneficial for industrial and automotive applications requiring wider temperature operation and enhanced protection.

Q: Can the package difference between SOT-25 and SOT-23-5 affect circuit performance?

A: Package differences do not affect electrical performance but require PCB layout modifications. SOT-23-5 has a different pin configuration and footprint than SOT-25, necessitating new PCB design and assembly procedures. Thermal characteristics may also differ slightly due to package geometry variations.