Specifications
| Attribute | Value |
| Package | Tube |
| ProductStatus | Obsolete |
| OutputConfiguration | Positive |
| OutputType | Adjustable |
| NumberofRegulators | 1 |
| Voltage-Input(Max) | 40V |
| Voltage-Output(Min/Fixed) | 1.2V |
| Voltage-Output(Max) | 37V |
| Current-Output | 1.5A |
| PSRR | 80dB ~ 65dB (120Hz) |
| ProtectionFeatures | Over Current, Over Temperature, Short Circuit |
| OperatingTemperature | 0°C ~ 125°C |
| MountingType | Surface Mount |
| Package/Case | TO-263-3, D²Pak (2 Leads + Tab), TO-263AB |
Overview
Description
The LM317D2T is a versatile, adjustable three-terminal voltage regulator designed for a wide range of applications, providing an output voltage range from 1.25V to 37V with a maximum output current of 1.5A. It is commonly used in power supplies and battery chargers due to its ability to maintain a constant output voltage even when input voltages or load currents fluctuate. The regulator includes features such as current limiting, thermal overload protection, and safe operating area protection, enhancing its reliability and durability in various environments.
The LM317D2T is housed in a TO-263 surface-mount package, which is suitable for applications where space is limited. Its ease of use is notable; users typically need two external resistors to set the output voltage. Additionally, due to its robust design, it is used in applications ranging from consumer electronics to industrial equipment. The device's versatility and reliability make it a popular choice for engineers and hobbyists alike when designing adjustable power supply circuits.
The LM317D2T is housed in a TO-263 surface-mount package, which is suitable for applications where space is limited. Its ease of use is notable; users typically need two external resistors to set the output voltage. Additionally, due to its robust design, it is used in applications ranging from consumer electronics to industrial equipment. The device's versatility and reliability make it a popular choice for engineers and hobbyists alike when designing adjustable power supply circuits.
Equivalent
The LM317D2T is a voltage regulator. Equivalent products include:
1. LM317T: Popular variant with similar characteristics.
2. LM317M: Medium power version.
3. L78S05CV: Fixed 5V version with similar functionality.
4. MC7805CT: Fixed voltage alternative.
5. NTE956: Adjustable regulator replacement.
These alternatives may vary in packaging and specifications, so verify compatibility with your application requirements.
1. LM317T: Popular variant with similar characteristics.
2. LM317M: Medium power version.
3. L78S05CV: Fixed 5V version with similar functionality.
4. MC7805CT: Fixed voltage alternative.
5. NTE956: Adjustable regulator replacement.
These alternatives may vary in packaging and specifications, so verify compatibility with your application requirements.
Features
The LM317D2T is a versatile adjustable voltage regulator with several key features:
1. Adjustable Output Voltage: It provides an output voltage range from 1.25V to 37V, allowing for flexibility in various applications.
2. Output Current: The device can deliver output current up to 1.5A, making it suitable for powering a range of devices.
3. Line Regulation: Offers excellent line regulation, typically 0.01%/V, ensuring consistent performance with varying input voltages.
4. Load Regulation: Features good load regulation, typically 0.1%, maintaining stable output under different load conditions.
5. Thermal Overload Protection: Includes built-in thermal overload protection to prevent damage from overheating.
6. Current Limit Protection: Offers current limit protection, safeguarding the device and connected components from excessive current.
7. Safe Area Protection: Contains safe area protection for further device security.
8. Temperature Range: Operates over a wide temperature range, typically from -40°C to +125°C, suitable for diverse environments.
9. Dropout Voltage: Features a dropout voltage of around 3V, which is the minimum difference between input and output voltage for proper regulation.
These features make the LM317D2T a reliable choice for various power management applications.
1. Adjustable Output Voltage: It provides an output voltage range from 1.25V to 37V, allowing for flexibility in various applications.
2. Output Current: The device can deliver output current up to 1.5A, making it suitable for powering a range of devices.
3. Line Regulation: Offers excellent line regulation, typically 0.01%/V, ensuring consistent performance with varying input voltages.
4. Load Regulation: Features good load regulation, typically 0.1%, maintaining stable output under different load conditions.
5. Thermal Overload Protection: Includes built-in thermal overload protection to prevent damage from overheating.
6. Current Limit Protection: Offers current limit protection, safeguarding the device and connected components from excessive current.
7. Safe Area Protection: Contains safe area protection for further device security.
8. Temperature Range: Operates over a wide temperature range, typically from -40°C to +125°C, suitable for diverse environments.
9. Dropout Voltage: Features a dropout voltage of around 3V, which is the minimum difference between input and output voltage for proper regulation.
These features make the LM317D2T a reliable choice for various power management applications.
Pinout
The LM317D2T is a voltage regulator with three pins. Its primary function is to provide a stable output voltage that can be adjusted to any level between 1.25V to 37V, given the appropriate input voltage and external components.
The pins are as follows:
1. Input (IN): This pin receives the input voltage, which should be higher than the desired output voltage by at least 3V to ensure proper regulation.
2. Output (OUT): This pin provides the regulated output voltage. The voltage level is determined by the resistor network connected between the output and adjust pins.
3. Adjust (ADJ): This pin is used to set the output voltage. A resistor divider network is connected between the output and the adjust pin, which allows the output voltage to be set according to the formula: Vout = 1.25V * (1 + R2/R1) + Iadj * R2, where Iadj is typically very small and can often be neglected.
This configuration allows the LM317D2T to serve as a versatile and widely-used adjustable voltage regulator in various electronic applications.
The pins are as follows:
1. Input (IN): This pin receives the input voltage, which should be higher than the desired output voltage by at least 3V to ensure proper regulation.
2. Output (OUT): This pin provides the regulated output voltage. The voltage level is determined by the resistor network connected between the output and adjust pins.
3. Adjust (ADJ): This pin is used to set the output voltage. A resistor divider network is connected between the output and the adjust pin, which allows the output voltage to be set according to the formula: Vout = 1.25V * (1 + R2/R1) + Iadj * R2, where Iadj is typically very small and can often be neglected.
This configuration allows the LM317D2T to serve as a versatile and widely-used adjustable voltage regulator in various electronic applications.
Manufacturer
The LM317D2T is a voltage regulator manufactured by STMicroelectronics. STMicroelectronics is a global semiconductor company that designs, develops, manufactures, and markets a wide range of products, including integrated circuits and discrete devices. The company serves various industries, including automotive, industrial, personal electronics, and communications equipment. STMicroelectronics is known for its innovation in semiconductor solutions, providing technology that is integral to various applications, from consumer electronics to industrial automation and digital equipment.
Application
The LM317D2T is a versatile, adjustable voltage regulator used in various applications. Common areas include power supply regulation, where it stabilizes output voltage in electronic circuits. It's often used in battery chargers, providing consistent charging voltages. In embedded systems, it regulates power for microcontrollers and other components. The LM317D2T also finds use in LED drivers, offering constant current to LEDs. Additionally, it's suitable for DIY electronics projects, test equipment, and any application requiring a reliable, adjustable power supply. Its ability to handle a wide range of input voltages and deliver adjustable output makes it ideal for diverse electronic applications.
Package
The LM317D2T is a linear voltage regulator, and its package type is D2PAK, which is a surface-mount package. D2PAK is known for its heat dissipation capabilities, making it suitable for high-power applications.
