LM2585T-ADJ/NOPB | Texas Instruments

Flyback Converter, LM2585T-ADJ/NOPB, Texas Instruments

The LM2585T-ADJ/NOPB regulator is a monolithic integrated circuit specifically designed for flyback, step-up (boost), and forward converter applications. Requiring a minimum number of external components, this regulator is cost effective and simple to use. Included in the datasheet is a typical circuit of a boost or flyback regulator. Also listed is a selector guide for a diode and a capacitor, and a family of standard inductors and flyback transformers designed to work with this switching regulator.

The power switch is a 3-A NPN device that can stand off 65 V. Protecting the power switch is a current and thermal limiting circuit, and an undervoltage lockout circuit. This IC contains a 100-kHz fixed-frequency internal oscillator that permits the use of a small magnetic component. Other features include soft start mode to reduce in-rush current during start-up, current mode control for improved rejection of input voltage and output load transients, and cycle-by-cycle current limiting. An output voltage tolerance of ±4%, within specified input voltage and output load conditions, is specified for the power supply system.

Features

• Current-mode Operation for Improved Transient Response, Line Regulation, and Current Limit
• 100-kHz Switching Frequency
• Internal Soft-Start Function Reduces In-rush Current During Start-up
• Output Transistor Protected by Current Limit, Undervoltage Lockout, and Thermal Shutdown

Applications

• Flyback Regulator
• Multiple-output Regulator
• Simple Boost Regulator
• Forward Converter