¡ Semiconductor
FEDL6665C-02
MSM6665C-xx
Various Frequency Calculation Method
• Original Clock Frequency and Blink Frequency
Blink cycle calculation
([Original clock cycle] x 5) x 214 = Blink cycle ............................................. Formula 1
From formula 1, the blink frequency can be calculated.
Example)
When the original clock frequency is 80kHz.
Clock cycle Ts=12.5[µs]
From formula 1,
Blink cycle Tb=(12.5 x 10-6 x 5) x 214 = 1.024 [s]
Thus,
Blink frequency = 1 [Hz]
• Original Clock Frequency and Frame Frequency
Frame cycle calculation
1/9 DUTY: (Original clock cycle) x 1152 = Frame cycle ............................. Formula 2
1/17 DUTY: (Original clock cycle) x 1088 = Frame cycle ........................... Formula 3
From Formula 2,3 the blink frequency can be calculated.
Example)
In the original clock 80kHz and 1/17 DUTY specifications
Clock cycle Ts=12.5 [µs]
From formula 3,
Clock cycle Tf=12.5 x 10-6 x 1088 = 13.6 [ms]
Thus,
Frame frequency = 73.5 [Hz]
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