Fixed Buck Step-Down Switching Regulator, 4.5V-40V In, 3.3V 500mA Out, SOIC-8

This Fixed Buck Step-Down Switching Regulator from Texas Instruments is capable of driving a 0.5A load with excellent line and load regulation. Designed for simplicity, it requires a minimum number of external components and features internal frequency compensation, a fixed-frequency oscillator, and improved regulation specifications.

Operating at a switching frequency of 150kHz, this regulator allows the use of smaller-sized filter components compared to lower-frequency switching alternatives. Its high efficiency means that the copper traces on the printed circuit board are normally the only heat sinking required, streamlining your PCB layout.

The design is further simplified by the availability of standard inductors—both through-hole and surface-mount types—optimised for use with this series. It includes an external shutdown feature with a typical standby current of 85µA, alongside TTL shutdown capability, thermal shutdown, and current-limit protection for robust and reliable operation. Additionally, it is a green product free from antimony (Sb) and bromine (Br).

Key Features

• Fixed output voltage
• Requires only 4 external components
• TTL shutdown capability
• High efficiency
• Uses readily-available standard inductors
• Thermal shutdown and current-limit protection
• Green product (no Sb/Br)