The MC34083P is a monolithic high voltage power switching regulator specifically designed for off-line converters and regulators. This device incorporates all the primary functions necessary for implementing efficient power conversion topologies. It is specifically designed to minimize external component count and simplify the design of isolated power supplies. It is a robust and reliable solution for various power applications.

Applications:

• Off-line power supplies
• DC-DC converters
• Battery chargers
• Adapter power supplies
• Standby power systems

Features:

• High voltage operation (up to 400V)
• Internal start-up circuitry
• Pulse-width modulation (PWM) control
• Cycle-by-cycle current limiting
• Overvoltage protection
• Undervoltage lockout
• Thermal shutdown protection
• Low standby current
• Integrated error amplifier

Benefits:

• Simplified power supply design due to integrated features.
• High efficiency due to PWM control.
• Robust protection against overvoltage, undervoltage, and overtemperature conditions.
• Reduced component count, leading to smaller and more cost-effective power supplies.
• Improved system reliability due to built-in protection features.
• Lower power consumption in standby mode.

Additional Details:

The MC34083P operates by directly rectifying the AC line voltage. The high-voltage start-up circuitry enables direct connection to the rectified AC line, eliminating the need for an external start-up resistor. This reduces power dissipation and improves overall efficiency. The PWM control regulates the output voltage by adjusting the duty cycle of the switching transistor. Cycle-by-cycle current limiting protects the switching transistor from overcurrent conditions. The overvoltage and undervoltage lockout features ensure that the device operates within its safe operating area. The thermal shutdown protection prevents the device from overheating and protects the power supply from catastrophic failure. The integrated error amplifier allows for easy implementation of closed-loop voltage regulation. This regulator is available in a DIP package.