Datasheet

Product data sheet Rev. 2.2 — 11 March 2014 27 of 77

NXP Semiconductors

LPC11U3x

32-bit ARM Cortex-M0 microcontroller

consumption by eliminating all dynamic power use in any peripherals that are not required

for the application. Selected peripherals have their own clock divider which provides even

better power control.

7.18.5.1 Power profiles

The power consumption in Active and Sleep modes can be optimized for the application

through simple calls to the power profile. The power configuration routine configures the

LPC11U3x for one of the following power modes:

• Default mode corresponding to power configuration after reset.

• CPU performance mode corresponding to optimized processing capability.

• Efficiency mode corresponding to optimized balance of current consumption and CPU

performance.

• Low-current mode corresponding to lowest power consumption.

In addition, the power profile includes routines to select the optimal PLL settings for a

given system clock and PLL input clock.

Remark: When using the USB, configure the LPC11U3x in Default mode.

7.18.5.2 Sleep mode

When Sleep mode is entered, the clock to the core is stopped. Resumption from the Sleep

mode does not need any special sequence but re-enabling the clock to the ARM core.

In Sleep mode, execution of instructions is suspended until either a reset or interrupt

occurs. Peripheral functions continue operation during Sleep mode and can generate

interrupts to cause the processor to resume execution. Sleep mode eliminates dynamic

power used by the processor itself, by memory systems and related controllers, and by

internal buses.

7.18.5.3 Deep-sleep mode

In Deep-sleep mode, the LPC11U3x is in Sleep-mode and all peripheral clocks and all

clock sources are off except for the IRC. The IRC output is disabled unless the IRC is

selected as input to the watchdog timer. In addition all analog blocks are shut down and

the flash is in stand-by mode. In Deep-sleep mode, the application can keep the watchdog

oscillator and the BOD circuit running for self-timed wake-up and BOD protection.

The LPC11U3x can wake up from Deep-sleep mode via reset, selected GPIO pins, a

watchdog timer interrupt, or an interrupt generating USB port activity.

Deep-sleep mode saves power and allows for short wake-up times.

7.18.5.4 Power-down mode

In Power-down mode, the LPC11U3x is in Sleep-mode and all peripheral clocks and all

clock sources are off except for watchdog oscillator if selected. In addition all analog

blocks and the flash are shut down. In Power-down mode, the application can keep the

BOD circuit running for BOD protection.

The LPC11U3x can wake up from Power-down mode via reset, selected GPIO pins, a

watchdog timer interrupt, or an interrupt generating USB port activity.