FAN1117AD33X

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators Overview

The FAN1117AD33X is a fixed positive low dropout linear regulator manufactured by Fairchild Semiconductor, now part of onsemi. It provides a fixed 3.3V output with a maximum continuous current capability of 1A. The device operates within an input voltage range of 2.5V to 17V and features a typical dropout voltage of 1.2V at full load. It is housed in a TO-252 (DPAK) surface-mount package with three pins. The regulator includes internal thermal limiting and current limiting protection mechanisms to ensure safe operation under overload conditions.

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators Feature Summary

• Fixed 3.3V output voltage for stable power supply applications
• High current capability of 1A with low dropout performance
• Integrated thermal shutdown and current limit protection
• Surface-mount TO-252 package for efficient PCB layout

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators Applications

• Post-regulators for switching power supplies
• Battery charger circuits
• Motherboard clock supplies
• 12V to 3.3V linear regulation

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators Procurement Notes

Verify component authenticity as the FAN1117 series has been discontinued by onsemi. Check datasheet revisions for pinout consistency across legacy Fairchild and onsemi production runs. Confirm RoHS compliance status for specific manufacturing lots. Ensure replacement parts match electrical specifications exactly due to end-of-life status.

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators Selection Notes

Select this component when a fixed 3.3V rail is required with up to 1A load current. Consider the TO-252 package for thermal dissipation needs. Verify input voltage does not exceed 17V. Evaluate thermal resistance requirements for the application environment. Compare against newer LDO alternatives if long-term supply stability is critical.

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators Part Context

The FAN1117AD33X belongs to the FAN1117A family of low dropout regulators originally developed by Fairchild Semiconductor. This family includes adjustable and fixed voltage variants in various packages. The AD suffix indicates a fixed 3.3V output, while D33 specifies the voltage code. The X suffix typically denotes tape and reel packaging. The product line has transitioned to onsemi following corporate acquisition.

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators Replacement Considerations

Public confirmed substitute part numbers include LD1117DT33CTR from STMicroelectronics and LR1117AD33X from Leshan Radio Company. These components offer similar 1A current capability and 3.3V fixed output. Verify pin compatibility and thermal characteristics before substitution.