POWER ON RESET CIRCUIT FOR A DIGITAL DEVICE INCLUDING AN ON-CHIP VOLTAGE DOWN CONVERTER

摘要

A power on reset circuit initializes at power on a digital integrated circuit, and includes a first power on reset signal generator powered by an external power supply voltage and generates a first power on reset signal. A reference voltage generator is powered by the external power supply voltage, and is enabled by the first power on reset signal for generating a stable compensating reference voltage. A voltage down converter circuit receives the reference voltage and is enabled by the first power on reset signal, and converts the external applied power supply voltage to a stable regulated internal supply voltage. A second power on reset signal generator circuit receives the regulated internal supply voltage, and is enabled by the first power on reset signal for generating a second power on reset signal for core parts of the digital integrated circuit for initializing them at power on.