¡El MIC23099 is a high-efficiency, low-noise, dual-output, integrated power-management solution for single-cell alkaline or NiMH battery applications. ¡El synchronous boost output voltage (VOUT1) is enabled first and is powered from the battery. Next, the synchronous buck output (VOUT2) − which is powered from the boost output voltage − is enabled. This configuration allows VOUT2 to be independent of battery voltage, thereby allowing the buck output voltage to be higher or lower than the battery voltage. To minimize switching artifacts in the audio band, both the converters are design to operate with a minimum switching frequency of 80kHz for the buck and 100kHz for the boost. ¡El high current boost has a maximum switching frequency of 1MHz, minimizing the solution foot-print. ¡El MIC23099 incorporates both battery-management functions and fault protection. ¡El low-battery level is indicated by an external LED connected to the LED pin. In addition, a supervisory circuit monitors each output and asserts a power-good (PG) signal when the sequencing is done or de-asserted when a fault condition occurs.