The LT1121IST-3.3#PBF is a high-performance low dropout voltage regulator (LDO) from Linear Technology, now part of Analog Devices, designed to provide a fixed output of 3.3V with an input voltage range of up to 30V. This regulator is capable of delivering up to 150mA of continuous output current with a typical dropout voltage of just 0.4V at full load, making it an excellent choice for battery-powered devices and low voltage applications.

Key Features

• Low Dropout Voltage: The LT1121 operates with a very low dropout voltage, ensuring efficient regulation even when the input voltage is close to the output voltage.
• High Output Voltage Accuracy: This regulator maintains a high accuracy of ±3% over temperature, line, and load variations, providing a stable output for sensitive applications.
• Low Quiescent Current: With a quiescent current of only 20µA in operation and 10µA in shutdown, the LT1121 is optimized for battery-powered systems where power conservation is critical.
• Thermal Protection: It includes built-in thermal shutdown to protect the device under over-temperature conditions.
• Short-Circuit Protection: The LT1121 features short-circuit protection, enhancing the reliability of the device and the safety of the application it is used in.
• Stable with Low ESR Capacitors: The regulator is stable with output capacitors as low as 3.3µF, allowing the use of low-cost capacitors that have a low equivalent series resistance (ESR).

Applications

The LT1121IST-3.3#PBF is ideal for a wide range of applications, including:

• Portable Electronics
• Battery-Powered Equipment
• Microprocessor Supply
• Power Management for PDAs and Phones
• Automotive Electronics

Package and Quality

The device comes in a small, thermally efficient SOT-223 package, which is suitable for surface-mount technology (SMT) and is lead-free and RoHS compliant. The part number ends with PBF, indicating that it is lead (Pb) free. The LT1121IST-3.3#PBF is manufactured to high standards, ensuring reliable performance for critical applications.