AP1122TL-U Linear Voltage Regulator Equivalent & Substitute Parts

Part Overview

The AP1122TL-U is a linear voltage regulator IC manufactured by Diodes Incorporated, designed for positive fixed 1.2V output at 1A current capacity in a TO-220-3 package. This device is classified as obsolete, making identification of functionally equivalent substitute parts essential for ongoing design support and production continuity. The AP1122TL-U serves applications requiring low-voltage regulation with thermal and overcurrent protection in through-hole mounting configurations.

Substiute Parts

AP1122TL-U

Diodes IncorporatedIn Stock: 676AP1122TL-U Datasheet

Current PartRFQ

MCP1827S-1202E/AB

Microchip TechnologyIn Stock: 921MCP1827S-1202E/AB Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the AP1122TL-U is determined by the following critical parameters:

Fixed Output Voltage: 1.2V output is the primary functional requirement. Substitute parts must maintain this exact output voltage specification.

Package Compatibility: TO-220-3 through-hole package ensures mechanical and thermal interface compatibility with existing PCB designs.

Output Current Capability: The AP1122TL-U delivers 1A. Substitute parts with equal or greater current capacity (1A minimum) satisfy this requirement.

Input Voltage Range: Maximum input voltage of 12V establishes the upper operating limit. Substitute parts must accommodate this specification.

Protection Features: Over-current and over-temperature protection are baseline requirements. Substitute parts with equivalent or enhanced protection satisfy this criterion.

Regulatory Compliance: RoHS3 compliance and REACH unaffected status are mandatory for equivalent substitution.

The MCP1827S-1202E/AB meets all substitution criteria through matching output voltage, package type, and regulatory compliance, while providing enhanced performance characteristics.

Parameter Comparison

Engineering Selection Recommendations

The MCP1827S-1202E/AB is a direct functional substitute for the obsolete AP1122TL-U based on the following engineering criteria:

Output Voltage Match: Both devices provide fixed 1.2V output, meeting the primary functional requirement.

Package Compatibility: Identical TO-220-3 through-hole package enables direct PCB layout compatibility without redesign.

Current Capacity: The MCP1827S-1202E/AB provides 1.5A output current, exceeding the 1A requirement of the AP1122TL-U. This provides design margin for current-limited applications.

Regulatory Compliance: Both devices maintain ROHS3 compliance and REACH unaffected status, satisfying procurement and environmental requirements.

Active Product Status: The MCP1827S-1202E/AB is actively manufactured by Microchip Technology, ensuring long-term availability and supply chain continuity compared to the obsolete AP1122TL-U.

Design Consideration: The MCP1827S-1202E/AB specifies a maximum input voltage of 6V, compared to 12V for the AP1122TL-U. Applications requiring input voltages above 6V require circuit redesign or alternative substitute selection.

Frequently Asked Questions (FAQ)

Q: Can the MCP1827S-1202E/AB directly replace the AP1122TL-U without PCB modifications?

A: Yes, for applications with input voltages not exceeding 6V. Both devices use identical TO-220-3 through-hole packaging with the same pin configuration (input, ground, output). No PCB layout changes are required for mechanical and electrical interface compatibility.

Q: What is the primary limitation of the MCP1827S-1202E/AB as a substitute?

A: The MCP1827S-1202E/AB specifies a maximum input voltage of 6V, whereas the AP1122TL-U accepts up to 12V input. Applications requiring higher input voltages must either implement input voltage reduction circuitry or select an alternative substitute part.

Q: Does the MCP1827S-1202E/AB provide equivalent protection features?

A: The MCP1827S-1202E/AB provides enhanced protection compared to the AP1122TL-U. It includes over-temperature protection, short-circuit protection, and under-voltage lockout (UVLO), whereas the AP1122TL-U provides over-current and over-temperature protection only.

Q: Are there compliance or certification differences between these devices?

A: Both devices maintain ROHS3 compliance and REACH unaffected status. No compliance or certification differences exist that would prevent substitution from a regulatory standpoint.

Q: What is the significance of the lower quiescent current in the MCP1827S-1202E/AB?

A: The MCP1827S-1202E/AB draws 220 µA quiescent current compared to 10 mA for the AP1122TL-U. This represents lower standby power consumption, which is beneficial for battery-powered or low-power applications where the regulator operates without significant load current.

Q: Can the MCP1827S-1202E/AB be used in applications originally designed for 12V input?

A: No. The MCP1827S-1202E/AB is limited to 6V maximum input voltage. Applications requiring 12V input must either reduce the input voltage through external circuitry or select a different substitute part with higher input voltage rating.