Chapter 17
Low-Leakage Wakeup Unit (LLWU)
17.1 Introduction
NOTE
For the chip-specific implementation details of this module's
instances, see the chip configuration information.
The LLWU module allows the user to select up to 16 external pins and up to 8 internal
modules as interrupt wake-up sources from low-leakage power modes.
The input sources are described in the device's chip configuration details. Each of the
available wake-up sources can be individually enabled.
The RESET pin is an additional source for triggering an exit from low-leakage power
modes, and causes the MCU to exit both LLS and VLLS through a reset flow.
The LLWU module also includes two optional digital pin filters for the external wakeup
pins.
See
AN4503: Power Management for Kinetis and C MCUs
for further details on
using the LLWU.
17.1.1 Features
The LLWU module features include:
• Support for up to 16 external input pins and up to 8 internal modules with individual
enable bits for MCU interrupt from low leakage modes
• Input sources may be external pins or from internal peripherals capable of running in
LLS or VLLS. See the chip configuration information for wakeup input sources for
this device.
• External pin wake-up inputs, each of which is programmable as falling-edge, rising-
edge, or any change
K22F Sub-Family Reference Manual , Rev. 3, 7/2014
Freescale Semiconductor, Inc.
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