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24.4.2.2 Stop mode operation
Depending on clock restrictions related to the MCU core or core peripherals, the MCU is
brought out of stop when a compare event occurs and the corresponding interrupt is
enabled. Similarly, if CR1[OPE] is enabled, the comparator output operates as in the
normal operating mode and comparator output is placed onto the external pin. In Stop
modes, the comparator can be operational in both:
• High-Speed (HS) Comparison mode when CR1[PMODE] = 1
• Low-Speed (LS) Comparison mode when CR1[PMODE] = 0
It is recommended to use the LS mode to minimize power consumption.
If stop is exited with a reset, all comparator registers are put into their reset state.
24.4.2.3 Low-Leakage mode operation
When the chip is in Low-Leakage modes:
• The CMP module is partially functional and is limited to Low-Speed mode,
regardless of CR1[PMODE] setting
• Windowed, Sampled, and Filtered modes are not supported
• The CMP output pin is latched and does not reflect the compare output state.
The positive- and negative-input voltage can be supplied from external pins or the DAC
output. The MCU can be brought out of the Low-Leakage mode if a compare event
occurs and the CMP interrupt is enabled. After wakeup from low-leakage modes, the
CMP module is in the reset state except for SCR[CFF] and SCR[CFR].
24.4.2.4 Background Debug Mode Operation
When the microcontroller is in active background debug mode, the CMP continues to
operate normally.
24.4.3 Startup and operation
A typical startup sequence is listed here.
• The time required to stabilize COUT will be the power-on delay of the comparators
plus the largest propagation delay from a selected analog source through the analog
Freescale Semiconductor, Inc.
KL27 Sub-Family Reference Manual , Rev. 5, 01/2016
Chapter 24 Comparator (CMP)
407
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