AP1115BY18G-13 Equivalent & Substitute Parts

Part Overview

The AP1115BY18G-13 is a linear voltage regulator IC from Diodes Incorporated, delivering a fixed 1.8V output at 600mA in a SOT-89-3 surface mount package. This device is classified as obsolete, necessitating identification of active equivalent parts for new designs and ongoing production requirements. The part operates across an input voltage range up to 18V with integrated over-current and over-temperature protection.

Substiute Parts

AP1115BY18G-13

Diodes IncorporatedIn Stock: 2132AP1115BY18G-13 Datasheet

Current PartRFQ

MCP1703AT-1802E/MB

Microchip TechnologyIn Stock: 1120MCP1703AT-1802E/MB Datasheet

MFR RecommendedRFQ

RT9166A-18GXL

Richtek USA Inc.In Stock: 3573RT9166A-18GXL Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the AP1115BY18G-13 is determined by the following critical parameters:

• Fixed output voltage of 1.8V
• SOT-89-3 package compatibility
• Positive output configuration
• Surface mount mounting type
• Over-current and over-temperature protection

Two active substitute parts meet these core requirements: the MCP1703AT-1802E/MB (Microchip Technology) and the RT9166A-18GXL (Richtek USA Inc.). Both devices maintain the 1.8V fixed output and SOT-89-3 package form factor. However, they differ in output current capability, input voltage range, and quiescent current specifications, which determine their suitability for specific application contexts.

Parameter Comparison

Engineering Selection Recommendations

MCP1703AT-1802E/MB is suitable for applications where output current requirements do not exceed 200mA. This device offers superior quiescent current performance (5 µA versus 10 mA), making it advantageous for battery-powered or low-power standby applications. The extended operating temperature range (-40°C to 125°C) and active product status support long-term design continuity. The addition of short-circuit protection provides enhanced reliability. Input voltage capability reaches 16V, accommodating most standard supply rails.

RT9166A-18GXL maintains full 600mA output current capability, matching the original AP1115BY18G-13 specification. This device delivers superior voltage dropout performance (0.58V typical at 600mA), reducing thermal dissipation in current-limited applications. However, the maximum input voltage is limited to 5.5V, restricting use to lower-voltage supply domains. The higher quiescent current (300 µA) and narrower operating temperature range (-40°C to 85°C) represent trade-offs against dropout performance.

Both substitute parts carry ROHS3 compliance and active product status, ensuring regulatory alignment and supply chain availability.

Frequently Asked Questions (FAQ)

Q: Can the MCP1703AT-1802E/MB directly replace the AP1115BY18G-13 in all applications?

A: Direct replacement is limited by output current capability. The MCP1703AT-1802E/MB is rated for 200mA maximum output, while the AP1115BY18G-13 delivers 600mA. Substitution is valid only for applications drawing 200mA or less from the 1.8V rail.

Q: What are the input voltage constraints for each substitute?

A: The MCP1703AT-1802E/MB accepts input voltages up to 16V. The RT9166A-18GXL is limited to 5.5V maximum input. The original AP1115BY18G-13 accepts up to 18V. Selection depends on the available supply voltage in your system.

Q: How do quiescent current differences affect power consumption?

A: The MCP1703AT-1802E/MB draws 5 µA quiescent current, the AP1115BY18G-13 draws 10 mA, and the RT9166A-18GXL draws 300 µA. In standby or low-load conditions, the MCP1703AT-1802E/MB minimizes parasitic power draw, while the RT9166A-18GXL exhibits higher standby consumption.

Q: Are all three devices pin-compatible?

A: Yes. All three regulators use the SOT-89-3 package (TO-243AA), ensuring mechanical and electrical pin compatibility at the board level.

Q: Which substitute offers the best thermal performance?

A: The RT9166A-18GXL provides the lowest voltage dropout (0.58V typical at 600mA), reducing heat generation during full-current operation. This advantage applies only when input voltage does not exceed 5.5V.

Q: What is the temperature operating range difference?

A: The MCP1703AT-1802E/MB operates from -40°C to 125°C (junction temperature). The RT9166A-18GXL operates from -40°C to 85°C (ambient temperature). The original AP1115BY18G-13 operates from 0°C to 125°C (junction temperature). Application environment determines the appropriate selection.