General Description
The MAX1777/MAX1977/MAX1999 dual step-down, switch-mode power-supply (SMPS) controllers generate logic-supply voltages in battery-powered systems. The MAX1777/MAX1977/MAX1999 include two pulse-width modulation (PWM) controllers, adjustable from 2V to 5.5V or fixed at 5V and 3.3V. These devices feature two linear regulators providing 5V and 3.3V always-on outputs.

FEATUREs
♦ No Current-Sense Resistor Needed (MAX1999)
♦ Accurate Current Sense with Current-Sense
   Resistor (MAX1777/MAX1977)
♦ 1.5% Output Voltage Accuracy
♦ 3.3V and 5V 100mA Bootstrapped Linear
   Regulators
♦ Internal Soft-Start and Soft-Stop Output
   Discharge
♦ Quick-PWM with 100ns Load Step Response
♦ 3.3V and 5V Fixed or Adjustable Outputs
   (Dual Mode™)
♦ 4.5V to 24V Input Voltage Range
♦ Ultrasonic Pulse-Skipping Mode (25kHz min)
♦ Power-Good (PGOOD) Signal
♦ Overvoltage Protection Enable/Disable

APPLICATIONs
   Notebook and Subnotebook Computers
   PDAs and Mobile Communication Devices
   3- and 4-Cell Li+ Battery-Powered Devices