16 |
M 5 7 7 9
𝑂𝑂𝑢𝑢𝑢𝑢𝑢𝑢𝑢𝑢𝑢𝑢
𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑢𝑢
𝑅𝑅𝐷𝐷𝑅𝑅𝐷𝐷𝐷𝐷𝑅𝑅𝐷𝐷
=
�
𝑆𝑆𝑃𝑃𝑆𝑆𝑆𝑆𝑆𝑆𝑃𝑃𝑆𝑆
𝑀𝑀𝑆𝑆𝑃𝑃𝑆𝑆𝑀𝑀𝑢𝑢𝑀𝑀 − 𝐼𝐼𝑃𝑃𝑢𝑢𝑢𝑢𝑢𝑢
𝑅𝑅𝑃𝑃𝑆𝑆𝑅𝑅𝑆𝑆𝑃𝑃𝑆𝑆
𝑆𝑆𝑃𝑃𝑆𝑆𝑆𝑆𝑆𝑆𝑃𝑃𝑆𝑆
𝑀𝑀𝑆𝑆𝑃𝑃𝑆𝑆𝑀𝑀𝑢𝑢𝑀𝑀 − 𝑆𝑆𝑃𝑃𝑆𝑆𝑆𝑆𝑆𝑆𝑃𝑃𝑆𝑆
𝑀𝑀𝑆𝑆𝑀𝑀𝑆𝑆𝑀𝑀𝑢𝑢𝑀𝑀�
× 100%
Example:
The figures below and above display a PWM output direct-mapped to a Rate input. The minimum
expected input rate is 25 Hz and the maximum expected rate is 150 Hz. A value of 50 Hz read at the input is
then mapped to a PWM output with an 80% duty cycle.
𝑂𝑂𝑢𝑢𝑢𝑢𝑢𝑢𝑢𝑢𝑢𝑢
𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑢𝑢
𝐷𝐷𝐷𝐷𝐷𝐷𝐷𝐷𝐷𝐷𝐷𝐷
,
𝐸𝐸𝐸𝐸𝐸𝐸𝐸𝐸𝐸𝐸𝐸𝐸𝐷𝐷
=
�
150
𝐻𝐻𝐻𝐻 −
50
𝐻𝐻𝐻𝐻
150
𝐻𝐻𝐻𝐻 −
25
𝐻𝐻𝐻𝐻�
× 100% = 80%
Figure 19: Sensor output mapping diagram