LM3S1911-IRN20-A0T Luminary Micro, Inc., LM3S1911-IRN20-A0T Datasheet - Page 365

• Manufacturer Part Number: LM3S1911-IRN20-A0T
• Description: Microcontroller
• Manufacturer: Luminary Micro, Inc.

15
15.1
15.2
October 09, 2007
Analog Comparators
An analog comparator is a peripheral that compares two analog voltages, and provides a logical
output that signals the comparison result.
The LM3S1911 controller provides two independent integrated analog comparators that can be
configured to drive an output or generate an interrupt
Note:
A comparator can compare a test voltage against any one of these voltages:
■
■
■
The comparator can provide its output to a device pin, acting as a replacement for an analog
comparator on the board, or it can be used to signal the application via interrupts to cause it to start
capturing a sample sequence.
Block Diagram
Figure 15-1. Analog Comparator Module Block Diagram
Functional Description
Important:
The comparator compares the VIN- and VIN+ inputs to produce an output, VOUT.
An individual external reference voltage
A shared single external reference voltage
A shared internal reference voltage
Not all comparators have the option to drive an output pin. See the Comparator Operating
Mode tables for more information.
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
C0+
C1-
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
ACSTAT1
ACSTAT0
ACCTL1
ACCTL0
Comparator 1
Comparator 0
interrupt
interrupt
output
output
C1o
interrupt
C0o
interrupt
LM3S1911 Microcontroller
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