5V or Adjustable, Low-Voltage, Step-Up DC-DC Controller

The MAX608 low-voltage step-up controller operates from a 1.8V to 16.5V input voltage range. Pulse-frequency-modulation (PFM) control provides high efficiency at heavy loads, while using only 85µA (typical) when operating with no load. In addition, a logic-controlled shutdown mode reduces supply current to 2µA typical. The output voltage is factory-set at 5V or can be adjusted from 3V to 16.5V with an external resistor divider.

The MAX608 is ideal for two- and three-cell battery-powered systems. An operating frequency of up to 300kHz allows use with small surface-mount components.

The MAX608 operates in "bootstrapped" mode only (with the chip supply, OUT, connected to the DC-DC output). For a 12V output without external resistors, or for nonbootstrapped applications (chip supply connected to input voltage), refer to the pin-compatible MAX1771. The MAX608 is available in 8-pin DIP and SO packages.

Applications

* Battery-Powered Applications * High-Efficiency DC-DC Converters * Portable Communicators * Positive LCD-Bias Generators

* 1.8V to 16.5V Input Range

* 85% Efficiency for 30mA to 1.5A Load Currents

* Up to 10W Output Power

* 110µA Max Supply Current

* 5µA Max Shutdown Current

* Preset 5V or Adjustable Output (3V to 16.5V)

* Current-Limited PFM Control Scheme

* Up to 300kHz Switching Frequency

* Evaluation Kit Available