AS1326 Step-Up Converter IC

Description

The AS1326A/AS1326B are high-efficiency, high current, DC-DC step-up converters specifically designed for battery-powered wireless applications. Low quiescent supply current (65μA), high operating frequency (1MHz), and minimal external component requirements make these devices perfect for small hand-held applications.

Both devices use synchronous-rectified pulse-width modulation (PWM) boost technology to generate 2.5 to 5.0V outputs from a wide range of inputs, such as 1 to 3 alkaline/NiCd/NiMH cells or a single lithium-ion (Li+) cell.

Automatic powersave operation significantly improves efficiency at light-loads.

Continuous switching mode is available for applications requiring constant-frequency operation at all load currents. PWM operation can also be synchronized to an external clock to protect sensitive frequency bands in communications equipment.

Analog soft-start and adjustable current limit permit optimization of rush in current and external component size.

The AS1326A/AS1326B are available in a 10-pin TDFN (3.0mm x 3.0mm) package.

Key Features

• Input Range: 0.7V to 5.0V
• Adjustable Output: 2.5V to 5.0V
• Fixed Output: 3.3V
• 470mA @ 3.3V from a single AA Cell
• 620mA @ 5.0V from two AA Cells
• Constant-Frequency (1MHz) Operation
• Up to 96% Efficiency
• PWM Synchronous-Rectified Technology
• Logic-Controlled Shutdown: 0.1μA
• Synchronizable Switching Frequency (0.5 to 1.2MHz)
• Adjustable Current Limit
• Adjustable Soft-Start
• 10-pin TDFN (3.0mm x 3.0mm) Package

Applications

The devices are ideal for high-power portable devices including, PDA's, personal medical devices, wireless transmitters and receivers, Portable Video players and any other battery-operated, portable device.

Block diagram for AS1326 Step-Up Converter IC