STMICROELECTRONICS 78S18 Positive Voltage Regulator, 18V, 2A, TO-220

The STMICROELECTRONICS L78S18CV is a robust 3-terminal positive voltage regulator delivering a fixed 18V output. Designed for stability and reliability, it is an ideal solution for a wide range of electronic applications, providing local on-card regulation to eliminate the performance issues associated with remote, single-point power supplies.

Engineered for durability, this regulator integrates essential protective features including internal current limiting, thermal shutdown, and safe operating area (SOA) protection. These built-in safeguards make the device highly resilient, guarding against overloads, excessive heat, and short circuits. When paired with an adequate heatsink, it can deliver a continuous output current of over 2A, making it suitable for powering more demanding circuits.

Flexible Application

While configured as a fixed-voltage regulator, the L78S18CV offers design flexibility. It can be used in conjunction with external components to create adjustable voltage and current supplies, extending its usefulness beyond standard regulation tasks. Its primary role is in power management for industrial systems, consumer electronics, and prototyping, where a clean and stable 18V rail is required.

Key Specifications & Construction

• Output Voltage: Fixed at 18V nominal.
• Input Voltage Range: Operates from 21V to 35V DC input.
• Maximum Output Current: 2A (with sufficient heatsinking).
• Package Type: Industry-standard TO-220 through-hole package for easy mounting and effective heat dissipation.
• Pin Count: 3 pins.
• Operating Temperature Range: 0°C to 150°C.
• Protection Features: Internal current limit, thermal shutdown, and safe area protection.

Housed in a compact TO-220 package measuring 43mm x 33mm x 15mm, this regulator is easy to integrate into new designs or use as a reliable replacement component. Its