The UTCLD1117A-ADJ-A is an adjustable low dropout (LDO) positive voltage regulator manufactured by UTC (Unisonic Technologies Co., Ltd.). Unlike fixed-voltage regulators, this version allows the user to set the output voltage to a desired level within a specific range using external resistors. This adjustability makes it a versatile choice for applications requiring non-standard voltages or fine-tuning of power supplies.

Applications

• Adjustable power supplies
• Battery chargers
• Microcontroller power supplies
• Post regulators for switching power supplies
• Linear regulators for sensitive analog circuits
• Industrial control systems

Features

• Adjustable output voltage: Output voltage can be set by external resistors.
• Low dropout voltage: Ensures regulation with small input-output voltage differentials.
• Output current of 800mA: Delivers sufficient power for a range of applications.
• Over-temperature protection: Protects the regulator from thermal damage.
• Current limiting: Prevents excessive current flow, protecting the regulator and load.
• Reverse battery protection: Safeguards the regulator from damage due to reverse polarity.
• Available in SOT-223 package: Compact size for space-constrained applications.

Benefits

• Flexible output voltage setting: Provides customized power supply voltages.
• Stable and accurate regulation: Ensures proper operation of connected components.
• Efficient regulation: Minimizes power loss and heat generation.
• Protection features: Enhances reliability and prevents damage from common electrical faults.
• Ease of use: Simple to implement with just a few external resistors.
• Wide operating temperature range: Suitable for various environments.
• Long lifespan: High-quality design and components ensure durability.

Additional Details

The output voltage of the UTCLD1117A-ADJ-A is set using two external resistors, typically following the formula Vout = 1.25V * (1 + R2/R1), where R1 is connected between the ADJ pin and ground, and R2 is connected between the output pin and the ADJ pin. The input voltage range is typically between 3V and 15V. The dropout voltage is typically around 1.1V at the maximum output current. It requires a small output capacitor (typically a few microfarads) for stability. The SOT-223 package provides good thermal dissipation. Always refer to the official UTC datasheet for precise electrical characteristics, application guidelines, and recommended component values and resistor selection.

Proper PCB layout is crucial for optimal performance, especially regarding thermal management. Adequate heat sinking is necessary to prevent overheating, especially at higher input voltages and output currents. Careful resistor selection is important to ensure the desired output voltage and stable operation.