carpenter
Full Member level 6
I discovered a spell high resolution timer in STM32F334 and have question.
Can this timer be used to generate a clock signal to replace the crystal?
For example I need clock signal 13.56MHz with duty cycle 60%.
F= 13.56MHz
t = 73746,31268ps
HRTIM resolution 217ps
HRTIM_PERAR= 339,8447589 = 340 cycles
PER x DC= 0,6*340= 204
this will generate
t= 340*217=73780ps
F= 13553808,62 Hz
Delta F 13.56E6-13553808,62 = 6 191,38 Hz
error 6200ppm
For communication at 13.56MHz it is probably not sufficiently accurate, lae need for induction heating at 13.56MHz could be enough.
By the way, is it sufficiently precise for induction heating, or will there be a problem with legislation and regulators?
In any case, my calculation does not take into account errors in STM32F334 (PPL error, PWM output stability, etc.)
I wonder if it is possible to use HRTIM as crystal replacement or will it be very inaccurate and the clock will swim?
Can this timer be used to generate a clock signal to replace the crystal?
For example I need clock signal 13.56MHz with duty cycle 60%.
F= 13.56MHz
t = 73746,31268ps
HRTIM resolution 217ps
HRTIM_PERAR= 339,8447589 = 340 cycles
PER x DC= 0,6*340= 204
this will generate
t= 340*217=73780ps
F= 13553808,62 Hz
Delta F 13.56E6-13553808,62 = 6 191,38 Hz
error 6200ppm
For communication at 13.56MHz it is probably not sufficiently accurate, lae need for induction heating at 13.56MHz could be enough.
By the way, is it sufficiently precise for induction heating, or will there be a problem with legislation and regulators?
In any case, my calculation does not take into account errors in STM32F334 (PPL error, PWM output stability, etc.)
I wonder if it is possible to use HRTIM as crystal replacement or will it be very inaccurate and the clock will swim?