LD1117 3.3V Low Dropout Voltage Regulator, 800mA, TO-220

The LD1117V33C from STMicroelectronics is a robust and highly efficient low dropout (LDO) linear voltage regulator designed for stable, fixed 3.3V output. It is capable of delivering up to 800mA of output current, making it a versatile and reliable solution for a wide range of power management applications where consistent voltage is critical. Its high efficiency is assured by an NPN pass transistor architecture, which directs most of the quiescent current into the load rather than being wasted, contributing to better overall system performance.

A standout feature of this regulator is its very tight output voltage tolerance of ±1% at 25°C, achieved through on-chip trimming. This precision ensures your sensitive electronic circuits receive a stable and accurate supply voltage. Furthermore, the device maintains a 2% tolerance across its full operating temperature range from -40°C to 125°C, guaranteeing reliable operation in demanding environments.

The low dropout voltage is a key advantage. With a typical value of just 1V, it can maintain regulation even when the input voltage is only slightly higher than the desired 3.3V output, maximising efficiency and extending battery life in portable devices. Stability is easily achieved with only a common 10µF minimum capacitor on the output.

Housed in the industry-standard TO-220 package for through-hole mounting, this regulator features internal current and thermal limiting for robust overload protection. It also offers excellent supply voltage rejection of 75dB (typical), effectively filtering out noise and ripple from the input supply to deliver a clean, steady output.

Applications

This component is perfectly suited for power management in a variety of electronic systems, including:

• Power supplies for microcontrollers, FPGAs, and digital logic
• Battery-powered equipment
• Post-regulation for switching power