The KA78L18AZ is a three-terminal positive voltage regulator available in a TO-92 package. It is designed to provide a fixed 18V output voltage with minimal external components. The device includes built-in thermal overload protection and short-circuit current limiting, enhancing its reliability in various applications.

Applications

• Voltage regulation in electronic devices
• Power supply for small electronic circuits
• Instrumentation and control systems
• Battery charging circuits
• DIY electronics projects requiring a stable 18V supply

Features

• Fixed 18V output voltage
• Output current up to 100mA
• Internal thermal overload protection
• Short-circuit current limiting
• No external components required for basic operation

Benefits

• Provides a stable and regulated 18V supply for sensitive electronic components.
• Simplified circuit design reduces BOM cost and assembly time.
• Protects the regulator from damage due to overheating.
• Prevents damage to the regulator and connected circuitry in case of a short circuit.
• Easy to use and integrate into various electronic circuits.

Additional Details

The KA78L18AZ requires a minimum input voltage slightly higher than 18V (typically around 21V) to maintain regulation. The maximum input voltage is generally around 30V. The device is commonly used in applications where a simple and reliable 18V power supply is needed. A small bypass capacitor (e.g., 0.1µF) is often recommended at the input and output to improve stability and reduce noise. It operates over a temperature range from -40°C to +125°C. The output voltage tolerance is typically ±5%.