Features

• Synchronous Rectification: Up to 97% Efficiency
• 2A Switch Current Rating
• Fixed Frequency Operation Up to 3MHz
• Wide Input Range: 0.5V to 5V
• Very Low Quiescent Current: 38µA (Burst Mode Operation)
• 2.6V to 5V Adjustable Output Voltage
• 0.85V (Typ) Start-Up Voltage
• No External Schottky Diode Required (V_OUT < 4.3V)
• Synchronizable Switching Frequency
• Burst Mode Enable Control
• Antiringing Control Reduces Switching Noise
• PGOOD Output
• OPTI-LOOP Compensation
• Very Low Shutdown Current: <1µA
• Small 10-Pin MSOP Package

Typical Application

Description

The LTC3402 is a high efficiency, fixed frequency, step-up DC/DC converter that operates from an input voltage below 1V. The device includes a 0.16 Ohms N-channel MOSFET switch and a 0.18 Ohms P-channel synchronous rectifier. Switching frequencies up to 3MHz are programmed with an external timing resistor and the oscillator can be synchronized to an external clock. An external Schottky diode is optional but will slightly improve efficiency.

Quiescent current is only 38µA in Burst Mode operation, maximizing battery life in portable applications. Burst Mode operation is user controlled and can be enabled by driving the MODE/SYNC pin high. If the MODE/SYNC pin has either a clock or is driven low, then fixed frequency switching is enabled.

Other features include a 1µA shutdown, antiringing control, open-drain power good output, thermal shutdown and current limit. The LTC3402 is available in the 10-lead thermally enhanced MSOP package. Lower current applications should use the 1A rated LTC3401 synchronous boost converter. Applications that require V_OUT < 2.6V should use the LTC3424.