Product Description: STMicroelectronics LM317T

The LM317T is a popular adjustable voltage regulator from STMicroelectronics. It is widely used in electronic circuits to provide a stable, regulated output voltage for a variety of applications. The LM317T is a three-terminal device that can supply output voltages ranging from 1.25 V to 37 V with an output current of up to 1.5 A. Known for its reliability and ease of use, the LM317T is ideal for powering devices that require a stable and adjustable voltage.

Product Features:

• Adjustable Output Voltage: The LM317T allows for output voltages between 1.25 V and 37 V, making it flexible for a wide range of applications.
• Output Current: Capable of providing up to 1.5 A of output current, which is suitable for powering moderate loads.
• Low Dropout Voltage: The LM317T offers a low dropout voltage (typically 3 V) for greater efficiency in voltage regulation.
• Thermal Overload Protection: The regulator includes thermal overload protection, which ensures the device is not damaged due to excessive heat.
• Short-Circuit Protection: Built-in short-circuit protection prevents damage from a short at the output.
• Adjustable Output: By using an external resistor network, the output voltage can be adjusted precisely for specific application needs.
• Package: Available in the TO-220 package, providing good thermal performance for heat dissipation.
• Easy to Use: The LM317T is easy to integrate into designs and can be used with a variety of capacitors for input and output filtering.

Applications:

• Power Supply Circuits: Used in custom power supply designs where adjustable output voltage is required, such as in test equipment, battery chargers, and LED drivers.
• Battery Charging: Commonly used in battery charging circuits due to its ability to provide a stable, adjustable output voltage.
• Bench Power Supplies: Ideal for use in laboratory or test bench power supplies where precise voltage control is needed.
• Voltage Regulation in DIY Projects: Popular in hobbyist electronics and DIY projects for powering components that need a specific voltage.
• Voltage Regulators for Audio Equipment: Used in audio equipment to provide stable and noise-free voltage regulation for sensitive circuits.
• Regulated Power for Sensors: Can be used to provide clean and stable power to sensor circuits in embedded systems.

Frequently Asked Questions (FAQs):

1. What is the output voltage range of the LM317T?
The LM317T provides an adjustable output voltage range from 1.25 V to 37 V, which can be set by selecting appropriate resistors in the external feedback network.

2. What is the maximum output current of the LM317T?
The LM317T can supply up to 1.5 A of output current, making it suitable for moderate-power applications.

3. What is the dropout voltage of the LM317T?
The typical dropout voltage is about 3 V, meaning that the input voltage must be at least 3 V higher than the desired output voltage for proper regulation.

4. Can I use the LM317T to regulate voltage for sensitive equipment?
Yes, the LM317T is often used in circuits that require stable and clean output voltages, such as in audio systems or sensor circuits.

5. What package does the LM317T come in?
The LM317T is available in the TO-220 package, which provides efficient heat dissipation for high-power applications.

6. How do I adjust the output voltage of the LM317T?
The output voltage is set using an external resistor network, typically two resistors (R1 and R2), connected to the adjustment pin of the regulator. The output voltage is determined by the ratio of these resistors.

7. Is the LM317T suitable for low-power applications?
While the LM317T can supply up to 1.5 A of current, it is best suited for moderate-power applications. For very low-power applications, there are other voltage regulators with lower quiescent current.