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LM3S5D91 Datasheet, PDF (64/1340 Pages) Texas Instruments – Stellaris® LM3S5D91 Microcontroller
Architectural Overview
1.3.7.1
■ 16 digital comparators
■ On-chip voltage regulator
The following provides more detail on these analog functions.
ADC (see page 604)
An analog-to-digital converter (ADC) is a peripheral that converts a continuous analog voltage to a
discrete digital number. The Stellaris ADC module features 12-bit conversion resolution and supports
16 input channels plus an internal temperature sensor. Four buffered sample sequencers allow
rapid sampling of up to 16 analog input sources without controller intervention. Each sample
sequencer provides flexible programming with fully configurable input source, trigger events, interrupt
generation, and sequencer priority. Each ADC module has a digital comparator function that allows
the conversion value to be diverted to a comparison unit that provides eight digital comparators.
The LM3S5D91 microcontroller provides two ADC modules with the following features:
■ 16 shared analog input channels
■ 12-bit precision ADC with an accurate 10-bit data compatibility mode
■ Single-ended and differential-input configurations
■ On-chip internal temperature sensor
■ Maximum sample rate of one million samples/second
■ Optional phase shift in sample time programmable from 22.5º to 337.5º
■ Four programmable sample conversion sequencers from one to eight entries long, with
corresponding conversion result FIFOs
■ Flexible trigger control
– Controller (software)
– Timers
– Analog Comparators
– PWM
– GPIO
■ Hardware averaging of up to 64 samples
■ Digital comparison unit providing eight digital comparators
■ Converter uses an internal 3-V reference or an external reference
■ Power and ground for the analog circuitry is separate from the digital power and ground
■ Efficient transfers using Micro Direct Memory Access Controller (µDMA)
– Dedicated channel for each sample sequencer
64
January 22, 2012
Texas Instruments-Production Data