仕様
| 属性 | 値 |
| Package / Case | Tape & Reel (TR) |
| Part Status | Not For New Designs |
| Output Configuration | Positive |
| Output Type | Fixed |
| Number of Regulators | 1 |
| Voltage - Input (Max) | 7.5V |
| Voltage - Output (Min/Fixed) | 3.3V |
| Voltage Dropout (Max) | 0.2V @ 100mA |
| Current - Output | 1A |
| Protection Features | Over Temperature, Short Circuit |
| Operating Temperature | -40°C ~ 125°C |
| Mounting Type | Surface Mount |
概要
Description
The LM3940ISX-3.3 is a linear voltage regulator integrated circuit designed by Texas Instruments. It is specifically meant to convert a higher voltage, typically from a 5V power source, down to a stable 3.3V output. This makes it ideal for powering microcontrollers and other digital components that require a 3.3V supply.
Key features of the LM3940ISX-3.3 include a fixed output voltage of 3.3V, a dropout voltage of approximately 500 mV at full load, and a current output capacity of up to 1A. The regulator is also designed with thermal shutdown and current limiting features to protect against overheating and overcurrent conditions, enhancing the reliability of the applications it’s used in.
The device comes in an industry-standard TO-263 surface-mount package, facilitating easy integration onto printed circuit boards. Its efficient performance, combined with a low dropout voltage, makes the LM3940ISX-3.3 a practical choice for low-power 3.3V applications in consumer electronics, communications equipment, and other similar fields.
Key features of the LM3940ISX-3.3 include a fixed output voltage of 3.3V, a dropout voltage of approximately 500 mV at full load, and a current output capacity of up to 1A. The regulator is also designed with thermal shutdown and current limiting features to protect against overheating and overcurrent conditions, enhancing the reliability of the applications it’s used in.
The device comes in an industry-standard TO-263 surface-mount package, facilitating easy integration onto printed circuit boards. Its efficient performance, combined with a low dropout voltage, makes the LM3940ISX-3.3 a practical choice for low-power 3.3V applications in consumer electronics, communications equipment, and other similar fields.
Equivalent
The LM3940ISX-3.3 is a low-dropout (LDO) voltage regulator that outputs a fixed 3.3V. Equivalent products include:
1. LD1117-3.3 - Offers similar output with low dropout.
2. AMS1117-3.3 - Another widely used 3.3V LDO.
3. MIC29302WT - 3.3V LDO with comparable features.
4. TLV1117-33 - Provides similar voltage regulation.
Ensure compatibility regarding current rating, dropout voltage, and package type when selecting an alternative.
1. LD1117-3.3 - Offers similar output with low dropout.
2. AMS1117-3.3 - Another widely used 3.3V LDO.
3. MIC29302WT - 3.3V LDO with comparable features.
4. TLV1117-33 - Provides similar voltage regulation.
Ensure compatibility regarding current rating, dropout voltage, and package type when selecting an alternative.
Features
The LM3940ISX-3.3 is a low-dropout (LDO) linear voltage regulator designed to provide a stable 3.3V output from a higher voltage input. Key features include:
1. Low Dropout Voltage: It requires a minimal difference between input and output voltage, making it efficient for applications close to 3.3V.
2. Output Current Capability: Capable of delivering up to 1A of output current, suitable for powering moderate loads.
3. Output Voltage Accuracy: Provides an output voltage accuracy typically within ±2%, ensuring consistent voltage levels.
4. Thermal Protection: Includes thermal shutdown to prevent overheating, ensuring device reliability.
5. Short-circuit Protection: Protects against short-circuit conditions, enhancing safety.
6. Current Limiting: Incorporates current limiting to prevent excessive current draw, protecting both the regulator and the load.
7. Low Quiescent Current: Exhibits low quiescent current, which is beneficial for battery-powered applications.
8. Ease of Use: Requires minimal external components, simplifying circuit design.
These features make the LM3940ISX-3.3 ideal for applications that need reliable 3.3V power regulation, such as microcontroller power supplies and portable electronics.
1. Low Dropout Voltage: It requires a minimal difference between input and output voltage, making it efficient for applications close to 3.3V.
2. Output Current Capability: Capable of delivering up to 1A of output current, suitable for powering moderate loads.
3. Output Voltage Accuracy: Provides an output voltage accuracy typically within ±2%, ensuring consistent voltage levels.
4. Thermal Protection: Includes thermal shutdown to prevent overheating, ensuring device reliability.
5. Short-circuit Protection: Protects against short-circuit conditions, enhancing safety.
6. Current Limiting: Incorporates current limiting to prevent excessive current draw, protecting both the regulator and the load.
7. Low Quiescent Current: Exhibits low quiescent current, which is beneficial for battery-powered applications.
8. Ease of Use: Requires minimal external components, simplifying circuit design.
These features make the LM3940ISX-3.3 ideal for applications that need reliable 3.3V power regulation, such as microcontroller power supplies and portable electronics.
Pinout
The LM3940ISX-3.3 is a low-dropout voltage regulator specifically designed to provide a fixed output voltage of 3.3V. It comes in an 8-pin surface-mount package, typically the TO-263-5 or similar, but only three key pins are used for its basic operation:
1. Input (Vin): This pin receives the input voltage, which should be higher than 3.3V plus the dropout voltage to ensure proper regulation.
2. Output (Vout): This pin provides the regulated output voltage of 3.3V.
3. Ground (GND): This pin is the reference point for the input and output voltages.
The additional pins in the package are typically used for heat dissipation purposes (tab connected to ground) or may be no-connects (NC) depending on the specific package variant. The LM3940 is used in applications requiring a stable 3.3V supply, such as microcontrollers and other digital circuits, with a maximum output current of around 1A.
1. Input (Vin): This pin receives the input voltage, which should be higher than 3.3V plus the dropout voltage to ensure proper regulation.
2. Output (Vout): This pin provides the regulated output voltage of 3.3V.
3. Ground (GND): This pin is the reference point for the input and output voltages.
The additional pins in the package are typically used for heat dissipation purposes (tab connected to ground) or may be no-connects (NC) depending on the specific package variant. The LM3940 is used in applications requiring a stable 3.3V supply, such as microcontrollers and other digital circuits, with a maximum output current of around 1A.
Manufacturer
The LM3940ISX-3.3 is manufactured by Texas Instruments, an American technology company. Texas Instruments, often abbreviated as TI, is a company known for designing and manufacturing semiconductors and various integrated circuits, which are commonly used in electronic devices. Founded in 1930 and headquartered in Dallas, Texas, TI is one of the largest semiconductor companies in the world. It primarily focuses on developing analog chips and embedded processors, which are critical components in a wide range of electronics, spanning from consumer gadgets to industrial equipment. The company's products serve numerous markets, including automotive, industrial, personal electronics, communications equipment, and enterprise systems. Texas Instruments is recognized for its innovation and contribution to advancing technology in the semiconductor industry.
Application
The LM3940ISX-3.3 is a low dropout (LDO) linear voltage regulator designed to provide a stable 3.3V output from a higher input voltage, typically used in applications requiring efficient power conversion with minimal heat dissipation. It is commonly used in battery-powered devices, microcontroller applications, and systems transitioning from higher voltage sources to 3.3V logic levels. This regulator is ideal for powering components like microprocessors, microcontrollers, and other digital circuits requiring a 3.3V supply. Additionally, it's used in consumer electronics, telecommunications equipment, and industrial automation systems, where maintaining a stable voltage supply is crucial for performance and reliability.
Package
The LM3940ISX-3.3 is a voltage regulator integrated circuit provided in a surface-mount package. Specifically, it is available in a TO-263 package, which is a type of surface-mount plastic package with a tab for mounting, suitable for medium power applications.
