Datasheet

Analog Comparator (S08ACMPV2)
MC9S08JM16 Series Data Sheet, Rev. 2
130 Freescale Semiconductor
Figure 9-2. Analog Comparator 5V (ACMP5) Block Diagram
9.2 External Signal Description
The ACMP has two analog input pins, ACMP+ and ACMP– and one digital output pin ACMPO. Each of
these pins can accept an input voltage that varies across the full operating voltage range of the MCU. As
shown in Figure 9-2, the ACMP– pin is connected to the inverting input of the comparator, and the
ACMP+ pin is connected to the comparator non-inverting input if ACBGS is a 0. As shown in Figure 9-2,
the ACMPO pin can be enabled to drive an external pin.
The signal properties of ACMP are shown in Table 9-1.
9.3 Memory Map
9.3.1 Register Descriptions
The ACMP includes one register:
Table 9-1. Signal Properties
Signal Function I/O
ACMP– Inverting analog input to the ACMP.
(Minus input)
I
ACMP+ Non-inverting analog input to the ACMP.
(Positive input)
I
ACMPO Digital output of the ACMP. O
+
-
Interrupt
Control
Internal
Reference
ACBGS
Internal Bus
Status & Control
Register
ACMOD
set ACF
ACME
ACF
ACIE
ACOPE
Comparator
ACMP
INTERRUPT
REQUEST
ACMP+
ACMP–
ACMPO