LM3S5739 Datasheet, PDF (762/856 Pages) Texas Instruments – Stellaris® LM3S5739 Microcontroller

Analog Comparators
18.1
Block Diagram
Figure 18-1. Analog Comparator Module Block Diagram
C1-
-ve input _{Comparator 1}
C1+
+ve input
output
C1o
+ve input (alternate)
ACCTL1
trigger
trigger
ACSTAT1
interrupt
reference input
C0-
-ve input _{Comparator 0}
C0+
+ve input
output
C0o
+ve input (alternate)
ACCTL0
trigger
trigger
ACSTAT0
interrupt
reference input
internal
bus
Voltage
Ref
ACREFCTL
Interrupt Control
ACRIS
ACMIS
ACINTEN
interrupt
18.2
Signal Description
Table 18-1 on page 762 lists the external signals of the Analog Comparators and describes the
function of each. The Analog Comparator output signals are alternate functions for some GPIO
signals and default to be GPIO signals at reset. The column in the table below titled "Pin Assignment"
lists the possible GPIO pin placements for the Analog Comparator signals. The AFSEL bit in the
GPIO Alternate Function Select (GPIOAFSEL) register (page 378) should be set to choose the
Analog Comparator function. The positive and negative input signals are configured by clearing the
DEN bit in the GPIO Digital Enable (GPIODEN) register. For more information on configuring GPIOs,
see “General-Purpose Input/Outputs (GPIOs)” on page 355.
Table 18-1. Analog Comparators Signals (100LQFP)
Pin Name
Pin Number Pin Type Buffer Type^a Description
C0+
90
I
Analog Analog comparator 0 positive input.
C0-
92
I
Analog Analog comparator 0 negative input.
C0o
58
O
TTL
Analog comparator 0 output.
C1+
24
I
Analog Analog comparator 1 positive input.
C1-
91
I
Analog Analog comparator 1 negative input.
C1o
46
O
TTL
Analog comparator 1 output.
a. The TTL designation indicates the pin has TTL-compatible voltage levels.
762
November 17, 2011
Texas Instruments-Production Data