WP power up Sequence

The section of the spec states that “The host should not drive any signals to the module until >100 ms from the start of the
power-on sequence.”

What are the consequences of this? is this a logical issue or can the module be damaged by a “VGPIO” level voltage on the UART RX pin for example?

Does the module require HW protection on all inputs? There doesn’t seem to be such a protection on the MangoH board…

Thanks a lot,


So this section is standard in most of the products and reflects the chipsets data sheets. Essentially the concern is that if you apply power to the pins on the unit prior to the unit powering up you might partially power some part of the chipset which might lead to undefined/unforeseen consequences, as a result we need to state a known start state and this is it.

As you can see from several designs (mangOH, dev kits, etc) this does not happen as a rule and its as much about giving a known reference as anything else.