LM3S3749 Luminary Micro, Inc, LM3S3749 Datasheet - Page 37

• Manufacturer Part Number: LM3S3749
• Description: Lm3s3749 Arm Microcontroller
• Manufacturer: Luminary Micro, Inc

1.4.3
1.4.3.1
1.4.3.2
1.4.4
1.4.4.1
June 02, 2008
Analog Peripherals
To handle analog signals, the LM3S3749 microcontroller offers an Analog-to-Digital Converter
(ADC).
For support of analog signals, the LM3S3749 microcontroller offers two analog comparators.
ADC (see page 354)
An analog-to-digital converter (ADC) is a peripheral that converts a continuous analog voltage to a
discrete digital number.
The LM3S3749 ADC module features 10-bit conversion resolution and supports eight input channels,
plus an internal temperature sensor. Four buffered sample sequences allow rapid sampling of up
to eight analog input sources without controller intervention. Each sample sequence provides flexible
programming with fully configurable input source, trigger events, interrupt generation, and sequence
priority.
Analog Comparators (see page 591)
An analog comparator is a peripheral that compares two analog voltages, and provides a logical
output that signals the comparison result.
The LM3S3749 microcontroller provides two independent integrated analog comparators that can
be configured to drive an output or generate an interrupt or ADC event.
A comparator can compare a test voltage against any one of these voltages:
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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 or triggers to the
ADC to cause it to start capturing a sample sequence. The interrupt generation and ADC triggering
logic is separate. This means, for example, that an interrupt can be generated on a rising edge and
the ADC triggered on a falling edge.
Serial Communications Peripherals
The LM3S3749 controller supports both asynchronous and synchronous serial communications
with:
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UART (see page 386)
A Universal Asynchronous Receiver/Transmitter (UART) is an integrated circuit used for RS-232C
serial communications, containing a transmitter (parallel-to-serial converter) and a receiver
(serial-to-parallel converter), each clocked separately.
An individual external reference voltage
A shared single external reference voltage
A shared internal reference voltage
Three fully programmable 16C550-type UARTs
Two SSI modules
Two I
One USB 2.0 full-speed controller
2
C modules
Preliminary
LM3S3749 Microcontroller
37