I have not actually tried this, but you can select an external PWM clock source and send up to 5MHz along the CLK line. Of course, you have to generate this frequency continuously if you want flicker-free operation, and the data you send needs to be synchronized with this clock. You can also use the OE line to reset the PWM counter; if you reset the counter at 256 clocks, you now have 8 bit PWM, for example. Obviously this is much more processor intensive than relying on the internal PWM clock generator.
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I have not actually tried
I have not actually tried this, but you can select an external PWM clock source and send up to 5MHz along the CLK line. Of course, you have to generate this frequency continuously if you want flicker-free operation, and the data you send needs to be synchronized with this clock. You can also use the OE line to reset the PWM counter; if you reset the counter at 256 clocks, you now have 8 bit PWM, for example. Obviously this is much more processor intensive than relying on the internal PWM clock generator.