Engineer-to-Enginee r Not e EE-393
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Protecting ADSP-CM41x Devices from Input Clock/Power Supply Faults
Contributed by Prasant Rajagopal and David Harrington Rev 2 – April 25, 2018
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Introduction
The ADSP-CM41x processors feature peripherals such as the Oscillator Watchdog (OSCWD), the
Oscillator Comparator Unit (OCU), and the Voltage Monitoring Unit (VMU). These peripherals can be used
to determine faults in the clocks, identify power supply issues for the processor, allow for a controlled
shutdown of the flash memory and set the general-purpose I/O pins (GPIOs) to safe states. This EE-Note
describes how to use these architectural blocks effectively in systems designed around ADSP-CM41x
devices.
Figure 1: Clock and Power Supply Safety Blocks Block Diagram