• Single ended or differential operation
• Conversion tailgating for predictable latency
• Current Digital to Analog Converter
• Source or sink a configurable constant current
• 2× Analog Comparator
• Programmable speed/current
• Capacitive sensing with up to 8 inputs
• Analog Port
•
Ultra efficient Power-on Reset and Brown-Out Detector
•
Debug Interface
• 4-pin Joint Test Action Group (JTAG) interface
• 2-pin serial-wire debug (SWD) interface
2.4 Oscillators and Clocks
EFM32 Jade Gecko has six different oscillators integrated, as shown in
Table 2.1 EFM32 Jade Gecko Oscillators on page 7
Table 2.1. EFM32 Jade Gecko Oscillators
Oscillator
Frequency
Optional?
External
components
Description
HFXO
38 MHz - 40 MHz
No
Crystal
High accuracy, low jitter high frequency crystal oscillator. Tun-
able crystal loading capacitors are fully integrated.
HFRCO
1 MHz - 38 MHz
No
-
Medium accuracy RC oscillator, typically used for timing dur-
ing startup of the HFXO or if a precise oscillator is not re-
quired.
AUXHFRCO
1 MHz - 38 MHz
No
-
Medium accuracy RC oscillator, typically used as alternative
clock source for Analog to Digital Converter or Debug Trace.
LFRCO
32768 Hz
No
-
Medium accuracy frequency reference typically used for medi-
um accuracy RTCC timing.
LFXO
32768 Hz
Yes
Crystal
High accuracy frequency reference typically used for high ac-
curacy RTCC timing. Tunable crystal loading capacitors are
fully integrated.
ULFRCO
1000 Hz
No
-
Ultra low frequency oscillator typically used for the watchdog
timer.
The RC oscillators can be calibrated against either of the crystal oscillators in order to compensate for temperature and voltage supply
variations. Hardware support is included to measure the frequency of various oscillators against each other.
Oscillator and clock management is available through the Clock Management Unit (CMU), see section
2.5 Hardware CRC Support
EFM32 Jade Gecko supports a configurable CRC generation:
• 8, 16, 24 or 32 bit CRC value
• Configurable polynomial and initialization value
• Optional inversion of CRC value over air
• Configurable CRC byte ordering
• Support for multiple CRC values calculated and verified per transmitted or received frame
EFM32JG1 Reference Manual
System Overview
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