customer are using TPS40322RHBT,and noticed that its ENABLE requires max of 1V as below.
We are controlling it from the sequencer UCD90124ARGCT – which drives 3.3V , we don’t have series resistor.
Can I drive it with HIGH-Z but what the UCD90124ARGCT drives at power up ?
Do you have a solution ?
I do not cover this TPS device but I would assume that the 1.0V max for Vih is the level that guarantees that the part is operating not the maximum that can be applied to the pin. The absolute max ratings list 7V for all pins not specifically listed in the table.
But seeing that this pin controls softstart as well as enable, it would typically be driven from an open drain output to allow for the SS functionality.
As for the operation of the UCD90124A, the DS indicates that the the standard GPIO pins are Hi-Z during reset while the FPWM GPIO pins are driven low during reset. So using an FPWM/GPIO pin set as an open drain output would be the way to go.
