Low drop-out (LDO) voltage regulator
EM Microelectronic Marin

The EM6156 offers a high level of integration by combining voltage regulation, voltage monitoring and software monitoring using a watchdog. A comparator monitors the voltage applied at the VIN input comparing it with an internal voltage reference VREF. The power-on reset function is initialized after VIN reaches VREF and takes the reset output inactive after a delay TPOR. The reset output goes active low when the VIN voltage is less than VREF. The RESET output is guaranteed to be in a correct state for a regulated output voltage as low as 1.2V. The watchdog function monitors software cycle time and execution. If software clears the watchdog too slowly (incorrect execution) it will cause the system to be reset.
In EM6156, the voltage regulator has a low dropout voltage and a low quiescent current. The quiescent current increases only slightly in dropout prolonging battery life.
Built-in protection includes a positive transient absorber for up to 45 V (load dump) and the ability to survive an unregulated input voltage of -42 V (reverse battery). The input may be connected to ground or to a reverse voltage
without reverse current flowing from the output to the input.