Datasheet

Chapter 9 Analog Comparator (S08ACMPV3)
MC9S08DZ60 Series Data Sheet, Rev. 4
170 Freescale Semiconductor
9.1.4 Block Diagram
The block diagram for the analog comparator module is shown Figure 9-2.
Figure 9-2. Analog Comparator (ACMP) Block Diagram
9.2 External Signal Description
The ACMP has two analog input pins, ACMPx+ and ACMPx− and one digital output pin ACMPxO. 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 ACMPx- pin is connected to the inverting input of the comparator, and the
ACMPx+ pin is connected to the comparator non-inverting input if ACBGS is a 0. As shown in Figure 9-2,
the ACMPxO pin can be enabled to drive an external pin.
The signal properties of ACMP are shown in Table 9-1.
Table 9-1. Signal Properties
Signal Function I/O
ACMPx- Inverting analog input to the ACMP.
(Minus input)
I
ACMPx+ Non-inverting analog input to the ACMP.
(Positive input)
I
ACMPxO Digital output of the ACMP. O
+
-
Interrupt
Control
Internal
Reference
ACBGS
Internal Bus
Status & Control
Register
ACMOD
set ACF
ACME
ACF
ACIE
ACOPE
Comparator
ACMPx
INTERRUPT
REQUEST
ACMPx+
ACMPx-
ACMPxO