New ICs and control techniques for battery powered systems

This paper describes a new high frequency dual stepdown switching regulator controller that has high efficiency and provides a very integrated approach to producing the multiple number of voltages usually required in portable computer systems. It uses synchronous rectification to maximize the efficiency of the switching regulators. Also a "hysteretic" burst mode is included to produce a very efficient regulator at very low load current. A low dropout high current 12 V linear regulator is included for flash memory programming and a micropower 5 V linear regulator for keeping monitoring circuits alive at all times. The integration of two PWM controllers as well as other features, uses less power and board space and at the same time eliminates the difficulties associated with the interfacing between different blocks and synchronizing of the switchers.