21.
OSCCTRL – Oscillators Controller
21.1. Overview
The Oscillators Controller (OSCCTRL) provides a user interface to the XOSC, OSC16M, DFLL48M, and
FDPLL96M.
Through the interface registers, it is possible to enable, disable, calibrate, and monitor the OSCCTRL
sub-peripherals.
All sub-peripheral statuses are collected in the Status register (STATUS). They can additionally trigger
interrupts upon status changes via the INTENSET, INTENCLR, and INTFLAG registers.
21.2. Features
•
0.4-32MHz Crystal Oscillator (XOSC)
–
Tunable gain control
–
Programmable start-up time
–
Crystal or external input clock on XIN I/O
–
Clock failure detection with safe clock switch
–
Clock failure event output
•
16MHz Internal Oscillator (OSC16M)
–
Fast startup
–
4/8/12/16MHz output frequencies available
•
Digital Frequency Locked Loop (DFLL48M)
–
Internal oscillator with no external components
–
48MHz output frequency
–
Operates stand-alone as a high-frequency programmable oscillator in open loop mode
–
Operates as an accurate frequency multiplier against a known frequency in closed loop mode
•
Fractional Digital Phase Locked Loop (FDPLL96M)
–
48MHz to 96MHz output frequency
–
32kHz to 2MHz reference clock
–
A selection of sources for the reference clock
–
Adjustable proportional integral controller
–
Fractional part used to achieve 1/16th of reference clock step
Atmel SAM L22G / L22J / L22N [DATASHEET]
Atmel-42402E-SAM L22G / L22J / L22N_Datasheet_Complete-07/2016
207