SNLS757B June 2024 – November 2024 TUSB2E221
PRODMIX
The RESETB pin is an active-low reset pin that can also be used as a power-down pin.
The TUSB2E221 does not have power supply sequence requirements between VDD3V3 and VDD1V8.
Make sure the maximum VDD3V3 and VDD1V8 ramp time to reach minimum supply voltages is 2ms.
An internal power-on reset circuit along with the external RESETB input pin allows for proper initialization when RESETB is deasserted high prior to the power rails being valid. If RESETB deasserts high before the power supplies are stable, the internal power-on reset circuit can hold off internal reset until the supplies are stable.
After the RESETB deassertion, followed by internally generated reset signal and 1ms delay, CROSS pin is sampled and latched.
After the RESETB deassertion and after t_RH_READY, the TUSB2E221 is enabled and enters default state, ready to accept eUSB2 packets. Each repeater is either in host repeater mode or device repeater mode depending on the receipt of either host mode enable or peripheral mode enable.