MT3406

The MT3406 is a constant frequency, current mode step-down converter. The device integrates a main switch and a synchronous rectifier for high efficiency without an external Schottky diode. It is ideal for powering portable equipment that runs from a single cell Lithium-Ion (Li+) battery. The output voltage can be regulated as low as 0.6V. The MT3406 can also run at 100% duty cycle for low dropout operation, extending battery life in portable system. This device offers two operation modes, PWM control and PFM Mode switching control, which allows a high efficiency over the wider range of the load. The MT3406 is a high performance, 1A, 1.5MHz monolithic step-down converter. The MT3406 requires only three external power components (CIN, COUT and L). The Adjustable version can be programmed with external feedback to any voltage, ranging from 0.6V to the input voltage. At dropout operation, the converter duty cycle increases to 100% and the output voltage tracks the input voltage minus the RDS(ON) drop of the high-side MOSFET. The internal error amplifier and compensation provides excellent transient response, load, and line regulation. Soft start function prevents input inrush current and output overshoot during start up.

Applications

• Cellular and Smart Phones
• Wireless and DSL Modems
• PDAs
• Portable Instruments
• Digital Still and Video Cameras
• DTV

Key features

• High Efficiency: Up to 96%
• 1.5MHz Constant Frequency Operation
• 1A Output Current
• No Schottky Diode Required
• 2V to 6V Input Voltage Range
• Output Voltage as Low as 0.6V
• PFM Mode for High Efficiency in Light Load
• 100% Duty Cycle in Dropout Operation
• Low Quiescent Current: 10μA
• Slope Compensated Current Mode Control for Excellent Line and Load Transient Response
• Short Circuit Protection
• Thermal Fault Protection
• Inrush Current Limit and Soft Start
• Shutdown Current
• SOT23 - 5 package