S i M 3 L 1 x x
Rev 1.1
41
4.3.1. PLL (PLL0)
The PLL module consists of a dedicated Digitally-Controlled Oscillator (DCO) that can be used in Free-Running
mode without a reference frequency, Frequency-Locked to a reference frequency, or Phase-Locked to a reference
frequency. The reference frequency for Frequency-Lock and Phase-Lock modes can use one of multiple sources
(including the external oscillator) to provide maximum flexibility for different application needs. Because the PLL
module generates its own clock, the DCO can be locked to a particular reference frequency and then moved to
Free-Running mode to reduce system power and noise.
The PLL module includes the following features:
Three output ranges with output frequencies ranging from 23 to 50 MHz.
Multiple reference frequency inputs, including the RTC0 oscillator, Low Power Oscillator, and external
oscillator.
Three output modes: Free-Running Digitally-Controlled Oscillator, Frequency-Locked, and Phase-Locked.
Able to sense the rising edge or falling edge of the reference source.
DCO frequency LSB dithering to provide finer average output frequencies.
Spectrum spreading to reduce generated system noise.
Low jitter and fast lock times.\
All output frequency updates (including dithering and spectrum spreading) can be temporarily suspended
using the STALL bit during noise-sensitive measurements.
4.3.2. Low Power Oscillator (LPOSC0)
The Low Power Oscillator is the default AHB oscillator on SiM3L1xx devices and enables or disables automatically,
as needed.
The default output frequency of this oscillator is factory calibrated to 20
MHz,
and
a
divided
2.5
MHz
version
of
this
clock is also available as an AHB clock source.
The Low Power Oscillator has the following features:
20
MHz and divided 2.5
MHz frequencies available for the AHB clock.
Automatically starts and stops as needed.
4.3.3. Low Frequency Oscillator (LFOSC0)
The low frequency oscillator (LFOSC) provides a low power internal clock source for the RTC0 timer and other
peripherals on the device. No external components are required to use the low frequency oscillator, and the RTC1
and RTC2 pins do not need to be shorted together.
The Low Frequency Oscillator has the following features:
16.4
kHz output frequency.
4.3.4. External Oscillators (EXTOSC0)
The EXTOSC0 external oscillator circuit may drive an external crystal, ceramic resonator, capacitor, or RC
network. A CMOS clock may also provide a clock input. The external oscillator output may be selected as the AHB
clock or used to clock other modules independent of the AHB clock selection.
The External Oscillator control has the following features:
Support for external crystal, resonator, RC, C, or CMOS oscillators.
Support for external CMOS frequencies from 10
kHz to 50
MHz.
Support for external crystal frequencies from 10
kHz to 25
MHz.
Various drive strengths for flexible crystal oscillator support.
Internal frequency divide-by-two option available.
Summary of Contents for SiM3L1xx
Page 2: ...2 Rev 1 1 ...
Page 62: ...SiM3L1xx 62 Rev 1 1 6 2 SiM3L1x6 Pin Definitions Figure 6 2 SiM3L1x6 GQ Pinout ...
Page 63: ...SiM3L1xx Rev 1 1 63 Figure 6 3 SiM3L1x6 GM Pinout ...
Page 69: ...SiM3L1xx Rev 1 1 69 6 3 SiM3L1x4 Pin Definitions Figure 6 4 SiM3L1x4 GM Pinout ...
Page 74: ...SiM3L1xx 74 Rev 1 1 6 4 TQFP 80 Package Specifications Figure 6 5 TQFP 80 Package Drawing ...
Page 81: ...SiM3L1xx Rev 1 1 81 6 6 TQFP 64 Package Specifications Figure 6 9 TQFP 64 Package Drawing ...
Page 89: ...SiM3L1xx Rev 1 1 89 Figure 7 3 SiM3L1x4 GM Revision Information ...
