Features

• Two Independent Step-Up Converters
• Each Channel Delivers 3.3V at 100mA from a Single Alkaline/NiMH Cell or 3.3V at 200mA from Two Cells
• V_IN Start-Up Voltage: 680mV
• 1.5V to 5.25V V_OUT Range
• Up to 94% Efficiency
• Output Disconnect
• 1MHz Fixed Frequency Operation
• V_IN > V_OUT Operation
• Integrated Soft-Start
• Current Mode Control with Internal Compensation
• Burst Mode® Operation with 9μA IQ Each Channel
• Internal Synchronous Rectifier
• Logic Controlled Shutdown (I_Q < 1μA)
• Anti-Ring Control
• Low Profile (3mm × 3mm × 0.75mm) 12-Lead DFN Package

Typical Application

Description

The LTC®3535 is a dual channel, synchronous, fixed frequency step-up DC/DC converter with output disconnect. Extended battery life in single AA/AAA powered products is realized with a 680mV start-up voltage and operation down to 500mV once started.

A switching frequency of 1MHz minimizes solution footprint by allowing the use of tiny, low profile inductors and ceramic capacitors. The current mode PWM design is internally compensated, reducing external parts count. The LTC3535 features Burst Mode operation at light load conditions allowing it to maintain high efficiency over a wide range of load. Anti-ring circuitry reduces EMI by damping the inductor in discontinuous mode. Additional features include a low shutdown current of under 1μA and thermal shutdown.

The LTC3535 is housed in a 3mm × 3mm × 0.75mm DFN package.