Features

• Wide Input Voltage Range: 3V to 75V
• High Switch Voltage: 100V
• Low Quiescent Current: 4.5mA
• Internal 1A Switch
• Shutdown Mode Draws Only 120µA Supply Current
• Isolated Flyback Regulation Mode for Fully Floating Outputs
• Can Be Externally Synchronized
• Available in MiniDIP and TO-220 Packages
• Same Pinout as LT1072

Typical Application

Description

The LT1082 is a monolithic high voltage switching regulator. It can be operated in all standard switching configurations including buck, boost, flyback, forward, and inverting. A 1A high efficiency switch is included on the die along with all oscillator, control, and protection circuitry.

The LT1082 operates with supply voltages from 3V to 75V, switch voltage up to 100V and draws only 4.5mA quiescent current. It can deliver load power up to 20W with no external power devices. By utilizing current-mode switching techniques, it provides excellent AC and DC load and line regulation.

An externally activated shutdown mode reduces total supply current to 120µA typical for standby operation. Totally isolated and regulated outputs can be generated by using the optional “isolated flyback regulation mode” built into the LT1082, without the need for optocouplers or extra transformer windings.

The LT1082 has a unique feature to provide high voltage short-circuit protection. When the FB pin is pulled down to 0.6V and the current out of the pin reaches approximately 350µA, the switching frequency will shift down from 60kHz to 12kHz.