The LT1121CST-3.3#PBF is a high-performance, low dropout (LDO) voltage regulator from Linear Technology, designed to provide a stable and reliable power supply for a wide range of applications. This particular model offers a fixed output voltage of 3.3V, making it an ideal choice for powering 3.3V logic in electronic systems.

Key Features

• Low Dropout Voltage: The LT1121 series boasts a low dropout voltage, ensuring efficient operation even when the input voltage is close to the output voltage.
• High Output Current: Capable of delivering up to 150mA of continuous output current, this regulator can support a variety of loads.
• Stable with Low ESR Capacitors: The LT1121CST-3.3#PBF is stable with output capacitors that have a low equivalent series resistance (ESR), which is crucial for maintaining output accuracy and transient response.
• Low Quiescent Current: With a quiescent current of only 30µA (typical), this LDO is suitable for battery-powered applications where power conservation is critical.
• Overcurrent and Overtemperature Protection: Built-in safety features protect the device and the load in adverse conditions.
• No Protection Diodes Needed: Internal circuitry eliminates the need for additional protection diodes, simplifying the design and saving board space.

Applications

The LT1121CST-3.3#PBF is versatile and can be used in various applications, including:

• Battery-powered equipment
• Portable devices
• Microprocessor supply
• Electronic toys and games
• Reference voltage sources

Package Information

This voltage regulator is offered in a small SOT-223 package, which is ideal for space-constrained applications. The part number includes the "#PBF" suffix, indicating that it is a lead-free ("Pb-free") and RoHS compliant component, aligning with environmental standards and restrictions on hazardous substances.

Conclusion

The LT1121CST-3.3#PBF from Linear Technology is a reliable and efficient solution for applications requiring a fixed 3.3V output. It combines low dropout performance, high output current capability, and protection features in a compact package, making it a top choice for designers looking for an LDO voltage regulator that balances performance with practicality.