MC9S08DN60_08 Datasheet, PDF (164/356 Pages) Freescale Semiconductor, Inc – Microcontrollers

Chapter 9 Analog Comparator (S08ACMPV3)
9.1.4 Block Diagram
The block diagram for the analog comparator module is shown Figure 9-2.
Internal
Reference
ACBGS
ACME
Internal Bus
Status & Control
Register
ACIE
ACF
ACOPE
ACMPx
INTERRUPT
REQUEST
ACMPx+
ACMPx-
+
-
Comparator
Interrupt
Control
ACMPxO
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.
I
(Minus input)
ACMPx+ Non-inverting analog input to the ACMP.
I
(Positive input)
ACMPxO Digital output of the ACMP.
O
MC9S08DN60 Series Data Sheet, Rev 3
164
Freescale Semiconductor