SPRS357D August 2006 – June 2020 TMS320F28044
PRODUCTION DATA.
Refer to the PDF data sheet for device specific package drawings
No requirements are placed on the power up/down sequence of the various power pins to ensure the correct reset state for all the modules. However, if the 3.3-V transistors in the level shifting output buffers of the I/O pins are powered prior to the 1.8-V transistors, it is possible for the output buffers to turn on, causing a glitch to occur on the pin during power up. To avoid this behavior, power the VDD (core voltage) pins prior to or simultaneously with the VDDIO (input/output voltage) pins, ensuring that the VDD pins have reached 0.7 V before or at the same time as the VDDIO pins reach 0.7 V.
There are some requirements on the XRS pin:
No voltage larger than a diode drop (0.7 V) above VDDIO should be applied to any digital pin (for analog pins, it is 0.7 V above VDDA) prior to powering up the device. Voltages applied to pins on an unpowered device can bias internal p-n junctions in unintended ways and produce unpredictable results.