LM3S5G31 Datasheet, PDF (54/1223 Pages) Texas Instruments – Stellaris LM3S5G31 Microcontroller

Architectural Overview
1.3.5.3
■ Power control
– On-chip fixed Low Drop-Out (LDO) voltage regulator
– Hibernation module handles the power-up/down 3.3 V sequencing and control for the core
digital logic and analog circuits
– Low-power options for microcontroller: Sleep and Deep-sleep modes with clock gating
– Low-power options for on-chip modules: software controls shutdown of individual peripherals
and memory
– 3.3-V supply brown-out detection and reporting via interrupt or reset
■ Multiple clock sources for microcontroller system clock
– Precision Oscillator (PIOSC): On-chip resource providing a 16 MHz ±1% frequency at room
temperature
• 16 MHz ±3% across temperature
• Can be recalibrated with 7-bit trim resolution
• Software power down control for low power modes
– Main Oscillator (MOSC): A frequency-accurate clock source by one of two means: an external
single-ended clock source is connected to the OSC0 input pin, or an external crystal is
connected across the OSC0 input and OSC1 output pins.
• External crystal used with or without on-chip PLL: select supported frequencies from 1
MHz to 16.384 MHz.
• External oscillator: from DC to maximum device speed
– Internal 30-kHz Oscillator: on chip resource providing a 30 kHz ± 50% frequency, used during
power-saving modes
– 32.768-kHz external oscillator for the Hibernation Module: eliminates need for additional
crystal for main clock source
■ Flexible reset sources
– Power-on reset (POR)
– Reset pin assertion
– Brown-out reset (BOR) detector alerts to system power drops
– Software reset
– Watchdog timer reset
– MOSC failure
Programmable Timers (see page 549)
Programmable timers can be used to count or time external events that drive the Timer input pins.
Each GPTM block provides two 16-bit timers/counters that can be configured to operate independently
as timers or event counters, or configured to operate as one 32-bit timer or one 32-bit Real-Time
Clock (RTC). Timers can also be used to trigger analog-to-digital (ADC) conversions.
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July 03, 2014
Texas Instruments-Production Data