LPC1111 NXP [NXP Semiconductors], LPC1111 Datasheet - Page 26

• Manufacturer Part Number: LPC1111
• Description: 32-bit ARM Cortex-M0 microcontroller; up to 32 kB flash and 8 kB SRAM
• Manufacturer: NXP [NXP Semiconductors]

NXP Semiconductors
LPC1111_12_13_14_1
Product data sheet
7.15.5.1 Sleep mode
7.15.5.2 Deep-sleep mode
7.15.5.3 Deep power-down mode
7.16.1 Reset
7.16 System control
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 may generate
interrupts to cause the processor to resume execution. Sleep mode eliminates dynamic
power used by the processor itself, memory systems and related controllers, and internal
buses.
In Deep-sleep mode, the chip is in Sleep mode, and in addition analog blocks can be shut
down for increased power savings. The user can configure the Deep-sleep mode to a
large extent, selecting any of the oscillators, the PLL, BOD, the ADC, and the flash to be
shut down or remain powered during Deep-sleep mode. The user can also select which of
the oscillators and analog blocks will be powered up after the chip exits from Deep-sleep
mode.
The GPIO pins (up to 15 pins total) serve as external wake-up pins to a dedicated start
logic to wake up the chip from Deep-sleep mode.
The timing of the wake-up process from Deep-sleep mode depends on which blocks are
selected to be powered down during deep-sleep.
For lowest power consumption, the clock source should be switched to IRC before
entering Deep-sleep mode, all oscillators and the PLL should be turned off during
deep-sleep, and the IRC should be selected as clock source when the chip wakes up from
deep-sleep. The IRC can be switched on and off glitch-free and provides a clean clock
signal after start-up.
If power consumption is not a concern, any of the oscillators and/or the PLL can be left
running in Deep-sleep mode to obtain short wake-up times when waking up from
deep-sleep.
In Deep power-down mode, power is shut off to the entire chip with the exception of the
WAKEUP pin. The LPC1111/12/13/14 can wake up from Deep power-down mode via the
WAKEUP pin.
Reset has four sources on the LPC1111/12/13/14: the RESET pin, the Watchdog reset,
power-on reset (POR), and the BrownOut Detection (BOD) circuit. The RESET pin is a
Schmitt trigger input pin. Assertion of chip reset by any source, once the operating voltage
attains a usable level, starts the IRC and initializes the flash controller.
When the internal Reset is removed, the processor begins executing at address 0, which
is initially the Reset vector mapped from the boot block. At that point, all of the processor
and peripheral registers have been initialized to predetermined values.
All information provided in this document is subject to legal disclaimers.
Rev. 01 — 16 April 2010
32-bit ARM Cortex-M0 microcontroller
LPC1111/12/13/14
© NXP B.V. 2010. All rights reserved.
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