The internal GCLK frequency is configured by the Frequency Multiplier (FREQ_MUL), and is determined by the PWM resolution. The GCLK frequency can be calculated by the below equations:

Equation 3.

where

• f_{refresh_rate} means the refresh rate
• f_{frame_rate} means the frame rate
• K means the PWM resolution
• N_{sub_period} means the sub-period numbers within one frame
• N_{GCLK_seg} means the GCLK number per segment (Line switch time excluded)
• f_GCLK means GCLK frequency
• T_SW means line switching time
• N_{scan_line} means the scan line number
• T_blank means the blank time in one frame, equals to 0 in ideal configuration
• GS_max means the maximum grayscale that the device can output in one frame

Table 9-2 gives the values based on the system configuration and equation.

Considering SCLK frequency and FREQ_MUL, the SCLK can be 13.9 MHz, and FREQ_MUL can be 6. So the GCLK is 83.4 MHz.