High-voltage ultralow-quiescent-current watchdog LDO qualified by automotive applications

In automotive microcontroller or microprocessor power-supply applications, the watchdog is used to monitor the microcontroller working status to prevent software runaway. The watchdog should be independent of the microcontroller in a reliable system. The Texas Instruments TPS7B63xx-Q1 device is a family of 300mA watchdog LDOs designed for an operating voltage up to 40V, with typical quiescent current of only 19µA at light load. The devices integrate a programmable function for selecting a window watchdog or standard watchdog, with an external resistor to set the watchdog time within 9% accuracy. The PG pin on the devices indicate when the output voltage is stable and in regulation. The power-good delay period and power-good threshold can be adjusted by selecting external components. The devices also feature integrated short-circuit and overcurrent protection. The combination of such features makes these devices particularly flexible and suitable to supply microcontroller in automotive applications.