The LP3966ET-3.3 is a 800mA Fast Response Ultra Low Dropout (ULDO) Regulator manufactured by National Semiconductor (now Texas Instruments). This regulator is designed to provide a stable 3.3V output voltage from a lower input voltage with minimal dropout voltage and fast transient response. It is optimized for portable applications, battery-powered systems, and other applications where efficiency and transient performance are critical.

Applications

• Portable Devices: Smartphones, tablets, and other mobile devices.
• Battery-Powered Systems: Powering devices from batteries, such as Li-Ion or Li-Polymer.
• Microprocessor Core Power: Providing a stable 3.3V supply for microprocessors and microcontrollers.
• Post-Regulation for Switching Regulators: Improving the output voltage regulation of switching regulators.
• Noise-Sensitive Applications: Providing a clean and stable power supply for noise-sensitive circuits.

Features

• Ultra Low Dropout Voltage: Minimal voltage drop between input and output for extended battery life.
• Fast Transient Response: Rapid response to changes in load current, ensuring stable output voltage.
• 800mA Output Current: Capable of delivering up to 800mA of output current.
• Stable with Ceramic Output Capacitors: Stable operation with low-ESR ceramic output capacitors.
• Current Limiting: Limits the output current to protect the IC and the load.
• Thermal Shutdown: Shuts down the IC when the temperature exceeds a safe limit.
• Enable Pin: Enable pin for controlling the output state.
• Small Package: Available in a small package for space-constrained applications.

Benefits

• Extended Battery Life: Ultra-low dropout voltage maximizes battery life in portable devices.
• Stable Output Voltage: Provides a stable and regulated output voltage under varying load conditions.
• Simplified Design: Stable operation with ceramic output capacitors simplifies the design.
• Compact Solution: Small package size makes it suitable for space-constrained applications.
• Robust Protection: Built-in protection features ensure reliable operation.

Additional Details

The LP3966ET-3.3 utilizes a unique architecture to achieve ultra-low dropout voltage and fast transient response. The internal circuitry is carefully designed to minimize quiescent current and maximize efficiency. The device is stable with low-ESR ceramic output capacitors, eliminating the need for bulky tantalum or electrolytic capacitors. Texas Instruments (formerly National Semiconductor) provides detailed datasheets, application notes, and evaluation boards to assist designers in implementing the LP3966ET-3.3 in their applications. The device includes an enable pin that can be used to turn the output on or off, reducing power consumption when the regulator is not needed.