Datasheet

Product data sheet Rev. 1.0 — 26 February 2019 36 of 123

NXP Semiconductors

LPC55S6x

32-bit ARM Cortex-M33 microcontroller

6.1.1 Termination of unused pins

Table 4 shows how to terminate pins that are not used in the application. In many cases,

unused pins should be connected externally or configured correctly by software to

minimize the overall power consumption of the part.

Unused pins with GPIO function should be configured as outputs set to LOW with their

internal pull-up disabled. To configure a GPIO pin as output and drive it LOW, select the

GPIO function in the IOCON register, select output in the GPIO DIR register, and write a 0

to the GPIO PORT register for that pin. Disable the pull-up in the pin’s IOCON register.

In addition, it is recommended to configure all GPIO pins that are not bonded out on

smaller packages as outputs driven LOW with their internal pull-up disabled.

[1] I = Input, IA = Inactive (no pull-up/pull-down enabled), PU = Pull-Up enabled

6.1.2 Pin states in different power modes

[1] Default and programmed pin states are retained in Sleep, Deep-sleep, and Power-down modes.

Table 4. Termination of unused pins (TBD)

Pin Default

state

[1]

Recommended termination of unused pins

Table 5. Pin states in different power modes (TBD)

Pin Active Sleep Deep-sleep Power-down Deep power-down