LM3S6938 Luminary Micro, Inc, LM3S6938 Datasheet - Page 458

• Manufacturer Part Number: LM3S6938
• Description: Lm3s6938 Arm Microcontroller
• Manufacturer: Luminary Micro, Inc

Analog Comparators
17.1
17.2
458
Block Diagram
Figure 17-1. Analog Comparator Module Block Diagram
Functional Description
Important:
The comparator compares the VIN- and VIN+ inputs to produce an output, VOUT.
VIN- < VIN+, VOUT = 1
VIN- > VIN+, VOUT = 0
As shown in Figure 17-2 on page 459, the input source for VIN- is an external input. In addition to
an external input, input sources for VIN+ can be the +ve input of comparator 0 or an internal reference.
It is recommended that the Digital-Input enable (the GPIODEN bit in the GPIO module)
for the analog input pin be disabled to prevent excessive current draw from the I/O
pads.
internal
C2+
C1+
C0+
C2-
C1-
C0-
bus
ACREFCTL
Voltage
Ref
Preliminary
-ve input
+ve input
+ve input (alternate)
reference input
-ve input
+ve input
+ve input (alternate)
reference input
-ve input
+ve input
+ve input (alternate)
reference input
ACSTAT2
ACSTAT1
ACSTAT0
ACCTL2
ACCTL1
ACCTL0
Comparator 2
Comparator 1
Comparator 0
interrupt
interrupt
interrupt
trigger
trigger
trigger
output
output
output
<none>
C1o
C0o
trigger
trigger
trigger
Interrupt Control
ACINTEN
interrupt
ACRIS
ACMIS
July 25, 2008