3A, 800kHz Step-Up Switching Regulator

The LT3436 is an 800kHz monolithic boost switching regulator. A high efficiency 3A, 0.1Ω switch is included on the die together with all the control circuitry required to complete a high frequency, current-mode switching regulator. Current-mode control provides fast transient response and excellent loop stability.

New design techniques achieve high efficiency at high switching frequencies over a wide operating range. A low dropout internal regulator maintains consistent performance over a wide range of inputs from 24V systems to Li- Ion batteries. An operating supply current of 1mA maintains high efficiency, especially at lower output currents. Shutdown reduces quiescent current to 11µA. Maximum switch current remains constant at all duty cycles. Synchronization capability allows an external logic level signal to increase the internal oscillator from 1MHz to 1.4MHz.

Full cycle-by-cycle switch current limit protection and thermal shutdown are provided. High frequency operation allows the reduction of input and output filtering components and permits the use of tiny chip inductors. The LT3436 is available in an exposed pad, 16-pin TSSOP package.

*Patent numbers 6,535,042; 6,611,131; 6,498,466

Applications

* DSL Modems

* Portable Computers

* Battery-Powered Systems

* Distributed Power

* Constant 800kHz Switching Frequency

* Wide Operating Voltage Range: 3V to 25V

* High Efficiency 0.1Ω/3A Switch

* 1.2V Feedback Reference Voltage

* ±2% Overall Output Voltage Tolerance

* Uses Low Profile Surface Mount External Components

* Low Shutdown Current: 11µA

* Synchronizable from 1MHz to 1.4MHz

* Current-Mode Control

* Constant Maximum Switch Current Rating at All Duty Cycles*

* Available in a Small Thermally Enhanced TSSOP-16 Package