Texas Instruments

LP3990MF-1.2

LP3990MF-1.2 Description

The LP3990MF-1.2 is a fixed-output linear voltage regulator designed by Texas Instruments, offering a regulated output voltage of 1.2V with a maximum output current of 150mA. This regulator is housed in a compact SOT23-5 package, making it suitable for surface-mount applications where space is a critical consideration. The device is designed to operate with an input voltage range up to 6V and features a low dropout voltage of 0.2V at 150mA, ensuring efficient operation even at low input-to-output voltage differentials.

LP3990MF-1.2 Features

• Fixed Output Voltage: The LP3990MF-1.2 provides a stable 1.2V output voltage, ideal for applications requiring a precise and consistent power supply.
• Low Dropout Voltage: With a maximum dropout voltage of 0.2V at 150mA, this regulator maintains high efficiency and performance even when the input voltage is close to the output voltage.
• Low Quiescent Current: The device features a low quiescent current of 80 µA, minimizing power consumption during operation, which is particularly beneficial for battery-powered applications.
• Enable Control Feature: The regulator includes an enable pin, allowing for dynamic control of the output voltage, which can be used to conserve power or manage system states.
• Protection Features: Over-temperature and shortircuit-c protection ensure the device's reliability and longevity, safeguarding against potential damage from excessive heat or electrical faults.
• High PSRR: The regulator boasts a power supply rejection ratio (PSRR) of 55dB to 35dB across a frequency range of 1kHz to 10kHz, effectively filtering out noise from the input supply and providing a clean output voltage.
• Moisture Sensitivity Level: The device has an MSL rating of 1 (Unlimited), indicating that it is not sensitive to moisture, which is advantageous for manufacturing processes and long-term reliability.

LP3990MF-1.2 Applications

The LP3990MF-1.2 is well-suited for a variety of applications where a reliable, low-power, and compact voltage regulator is required. Some specific use cases include:

• Portable Devices: Ideal for battery-operated devices such as smartphones, tablets, and wearable electronics, where low power consumption and high efficiency are crucial.
• Embedded Systems: Suitable for microcontroller and microprocessor-based systems that require a stable 1.2V supply to power various components.
• Communication Equipment: Can be used in routers, modems, and other communication devices to provide a clean and stable power supply to sensitive analog and digital circuits.
• Medical Devices: Applicable in medical equipment where reliability and low noise are essential, such as portable medical monitors and diagnostic tools.

Conclusion of LP3990MF-1.2

The LP3990MF-1.2 from Texas Instruments is a robust and efficient linear voltage regulator that offers a fixed 1.2V output with a maximum current of 150mA. Its low dropout voltage, low quiescent current, and high PSRR make it an excellent choice for applications requiring high efficiency and low noise. The enable control feature and comprehensive protection mechanisms further enhance its versatility and reliability. Despite being marked as obsolete, the LP3990MF-1.2 remains a valuable component for designers seeking a compact, high-performance regulator for their low-power applications.