DS1227

The DS1227 Kickstarter is a unique CMOS circuit which combines power conversion and microenergy management functions for battery operated systems. Using its integral DC-DC converter, the DS1227 supplies +5V on demand from either a 3 or 6volt battery input. The primary +5V output, typically tied to the microcontroller's V_CC pin, is "kickstarted" on in response to any one of several possible momentary, external signal transitions.Two auxiliary +5V power supply outputs can then be independently enabled or disabled under software control. When the primary power supply output is disabled, also under software control, the auxiliary power supply outputs remain in the state selected. In this manner, individual portions of the system can be powered only when they are required, minimizing the energy consumption of the system.

The DS1227 activates or kickstarts the primary V_CC output in response to external momentary low-going signals. Examples of such signals include a clock/calendar alarm from a DS1283 Watchdog Timekeeper, or an incoming asynchronous serial data word from a host PC via the DS1275 Line Powered Transceiver, or a simple pushbutton switch.

In addition, the DS1227 kickstarts primary system power in response to activity detected by an external sensor circuit. In this case, the Kickstarter can be signalled at regular intervals, typically from a DS1283 Watchdog Timekeeper, to momentarily apply power to the sensor and monitor an input for an active response.

An application using the Kickstarter has the capability to wake-up from a ultra-low power state, perform a task using minimum energy, and then go back to sleep until the DS1227 is signalled to kickstart system operation once again.