ZHCSGW5C January 2017 – March 2025 CC2640R2F-Q1
PRODUCTION DATA
The CC2640R2F-Q1 device supports two external and two internal clock sources.
A 24MHz crystal is required as the frequency reference for the radio. This signal is doubled internally to create a 48MHz clock.
The 32kHz crystal is optional. Bluetooth® low energy requires a slow-speed clock with better than
±500 ppm accuracy if the device is to enter any sleep mode while maintaining a connection. The internal
32kHz RC oscillator can, in some use cases, be compensated to meet the requirements. The low-speed crystal oscillator is designed for use with a 32kHz watch-type crystal.
The internal high-speed oscillator (48MHz) can be used as a clock source for the CPU subsystem.
The internal low-speed oscillator (32.768kHz) can be used as a reference if the low-power crystal oscillator is not used.
The 32kHz clock source can be used as an external clocking reference through GPIO.