RX21A_15 Datasheet, PDF (83/132 Pages) Renesas Technology Corp – Renesas MCUs

RX21A Group
5. Electrical Characteristics
Note 2. When specifying the main clock oscillator stabilization time, load MOSCWTCR register with a stabilization time value that is
greater than the resonator-vendor-recommended value. When determining the main lock oscillation stabilization wait time, allow
an adequate margin (2 times is recommended) for the main clock oscillation stabilization time.
Start using the main clock in the main clock oscillation stabilization wait time (tMAINOSCWT) after setting up the main clock
oscillator for operation with the MOSCCR.MOSTP bit.
The indicated value is a reference value that is measured for an 8 MHz resonator.
Note 3. Sum of the main clock oscillation stabilization time and the PLL oscillation stabilization time.
Note 4. The indicated value is a reference value that is measured for an 8 MHz resonator.
Note 5. When specifying the sub-clock oscillation stabilization time, load SOSCWTCR register with a stabilization time value that is
greater than the resonator-vendor-recommended value. When determining the sub-clock oscillation stabilization wait time, allow
an adequate margin (2 times is recommended) for the sub-clock oscillation stabilization time. Start using the sub-clock in the
sub-clock oscillation stabilization wait time (tSUBOSCWT) after setting up the sub-clock oscillator for operation with the
SOSCCR.SOSTP or RCR3.RTCEN bit.
t_EXH
t_EXcyc
t_EXL
EXTAL external clock input
t_EXr
t_EXf
Figure 5.25 EXTAL External Clock Input Timing
VCC × 0.5
MOSCCR.MOSTP
Main clock oscillator output
Main clock
t_MAINOSC
t_MAINOSCWT
Figure 5.26 Main Clock Oscillation Start Timing
LOCOCR.LCSTP, ILOCOCR.ILCSTP
LOCO, IWDTCLK clock
t_LOCOWT
Figure 5.27 LOCO, IWDTCLK Clock Oscillation Start Timing
R01DS0129EJ0110 Rev.1.10
Aug 28, 2014
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