Rev1.0a | 33/50
CMT2300A
5.3 Operation State, Timing and Power Consumption
5.3.1 Startup Timing
After the chip VDD is powered up, the chip usually needs to wait about 1ms, then POR will release. After the release of the POR, the
crystal will start, the start time is N ms, depending on the characteristics of the crystal itself. After starting, the user need to wait for
the crystal settled, then the system starts working. The default setting is 2.48 ms. This time can be modified by writing
XTAL_STB_TIME <2:0> afterword (it has to be longer than the crystal inherent settling time). The chip stays in IDLE state until the
crystal is settled. After the crystal is settled, the chip perform calibration of each module and stay in SLEEP state after then to wait
for initialization configuration by user. The chip will back to IDLE state and redo startup steps upon reset at anytime.
POR
VDD
POR Release
<= 1 ms
XTAL Stablize
<= 2.48 ms
Block Calibrations
<= 6.5 ms
Enters the SLEEP State Ready
for customer initializing
XTAL Start up
<= N ms
Figure 15. Power-on Timing
The chip enters SLEEP state after calibration. From then on, the MCU can control the chip to switch to different operation states
through setting the register CHIP_MODE_SWT<7:0>.