The CC32xx system-on-chip includes the necessary clock and power management functionalities to build a stand-alone, battery-operated low-power solution. Key features follow:
- Primary clocks
- Slow clock: 32.768kHz (±250ppm)
- Used in RTC, Wi-Fi® beacon listen timing in low-power idle mode, and some of the chip internal sequencing
- On-chip, low-power 32kHz crystal oscillator
- Support for externally-fed 32.768kHz clock
- On-chip 32kHz RC oscillator for initial wakeup
- Fast clock: 40MHz (±20 ppm)
- Used in Wi-Fi® radio and MCU
- On-chip low phase-noise 40MHz crystal oscillator
- Support for externally fed, clean 40MHz clock (such as TCXO)
- System and peripheral clocks are derived from an internal PLL producing 240MHz
- Flexible reset scheme
- The following resets are supported in CC32xx:
- External chip reset pin: The entire chip, including power management, is reset when the nRESET pin is held low.
- Reset on hibernate: The entire core is reset when the chip goes through a hibernate cycle.
- Reset on watchdog: The application MCU is reset when the WDT expires.
- Soft-reset: The application MCU is reset by software.
- Complete system recovery from any scenario at which the scenario is stuck can be achieved by using a combination of WDT reset and hibernate sleep.
- On-chip power management
- Wide voltage mode: 2.1V to 3.6V
- Powered by battery (2×1.5V) or a regulated 3.3V supply
- A set of three on-chip high-efficiency DC/DC converters produce the internal module supply voltages when needed. These switching converters and their frequency plan are optimized to minimize interference to WLAN radio.
- DIG-DCDC: Produces 0.9V to 1.2V for the core digital logic
- ANA1-DCDC: Produces low-ripple 1.8V supply for the analog and RF
- PA-DCDC: Produces regulated 1.8V with extremely fast transient regulation for the WLAN RF transmit power amplifier
- A set of low-dropout regulators (LDOs) is used in the radio subsystem to further regulate and filter the ANA1-DCDC output before being fed to the analog circuits
- On-chip factory-trimmed accurate band-gap voltage reference ensures the regulator outputs are stable across process and temperature