LM3S5652 Luminary Micro, Inc, LM3S5652 Datasheet - Page 36

• Manufacturer Part Number: LM3S5652
• Description: Lm3s5652 Arm Microcontroller
• Manufacturer: Luminary Micro, Inc

Architectural Overview
1.4.2
1.4.2.1
1.4.3
1.4.3.1
1.4.3.2
36
Motor Control Peripherals
To enhance motor control, the LM3S5652 controller features Pulse Width Modulation (PWM) outputs.
PWM
Pulse width modulation (PWM) is a powerful technique for digitally encoding analog signal levels.
High-resolution counters are used to generate a square wave, and the duty cycle of the square
wave is modulated to encode an analog signal. Typical applications include switching power supplies
and motor control.
On the LM3S5652, PWM motion control functionality can be achieved through:
■
CCP Pins (see page 292)
The General-Purpose Timer Module's CCP (Capture Compare PWM) pins are software programmable
to support a simple PWM mode with a software-programmable output inversion of the PWM signal.
Analog Peripherals
To handle analog signals, the LM3S5652 microcontroller offers an Analog-to-Digital Converter
(ADC).
For support of analog signals, the LM3S5652 microcontroller offers one analog comparator.
ADC (see page 343)
An analog-to-digital converter (ADC) is a peripheral that converts a continuous analog voltage to a
discrete digital number.
The LM3S5652 ADC module features 10-bit conversion resolution and supports six 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 623)
An analog comparator is a peripheral that compares two analog voltages, and provides a logical
output that signals the comparison result.
The LM3S5652 microcontroller provides one analog comparator 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:
■
■
■
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.
The motion control features of the general-purpose timers using the CCP pins
An individual external reference voltage
A shared single external reference voltage
A shared internal reference voltage
Preliminary
June 02, 2008