Analog Comparator (S08ACMPVLPV1)

10.1.5Features

The ACMP has the following features:

Full rail-to-rail supply operation

Less than 40 mV of input offset

Less than 15 mV of hysteresis

Selectable interrupt on rising edge, falling edge, or either rising or falling edges of comparator output

Option to compare to fixed internal bandgap reference voltage

10.1.6Modes of Operation

10.1.6.1Wait Mode Operation

During wait mode the ACMP, if enabled, continues to operate normally. Also, if enabled, the interrupt can wake the MCU.

10.1.6.2Stop3 Mode Operation

If enabled, the ACMP continues to operate in stop3 mode and compare operation remains active. If ACOPE is enabled, comparator output operates in the normal operating mode and comparator output is placed onto the external pin. The MCU is brought out of stop when a compare event occurs and ACIE is enabled; ACF flag sets accordingly.

If stop is exited with a reset, the ACMP will be put into its reset state.

10.1.6.3Stop2 Mode Operation

During stop2 mode, the ACMP module is fully powered down. Upon wakeup from stop2 mode, the ACMP module is in the reset state.

10.1.6.4Active Background Mode Operation

When the microcontroller is in active background mode, the ACMP continues to operate normally.

10.1.7Block Diagram

The block diagram for the ACMP module follows.

MCF51QE128 MCU Series Reference Manual, Rev. 3

Freescale Semiconductor

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Freescale Semiconductor MCF51QE128RM manual Block Diagram, Wait Mode Operation, Stop3 Mode Operation, Stop2 Mode Operation