If an external device drives a positive voltage to the signal pads and the CC3200MOD is not powered, DC current is drawn from the other device. If the drive strength of the external device is adequate, an unintentional wakeup and boot of the CC3200MOD can occur. To prevent current draw, TI recommends any one of the following:

• All devices interfaced to the CC3200MOD must be powered from the same power rail as the chip.
• Use level-shifters between the module and any external devices fed from other independent rails.
• The nRESET pin of the CC3200MOD must be held low until the VBAT supply to the module is driven and stable. This is automatically done within the module if this pin is left unconnected.