XT1780

XT1780 8MHz PWM Synchronous Buck Regulator with LDO Standby Mode ■ General Description The XT1780 is a high efficiency 8MHz pulse width modulated (PWM) synchronous buck (step-down) regulator that features a LOWQ LDO standby mode that draws only 25µA of quiescent current. The XT1780 allows an ultra-low noise, small size, and high efficiency solution for portable power applications. In PWM mode, the XT1780 operates with a constant frequency 8MHz PWM control. Under light load conditions, such as in system sleep or standby modes, the PWM switching operation can be disabled to reduce switching losses. In this light load LDO mode, the LDO maintains the output voltage and draws only 25µA of quiescent current. The LDO mode of operation saves battery life while not introducing spurious noise and high ripple as experienced with pulse skipping or bursting mode regulators. The XT1780 operates from a 2.7V to 5.5V input voltage and features internal power MOSFETs that can supply up to 800mA out...