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Hello, I'm interesting by the CAT4104 for my new design. In the datasheet, I read this : 1 - "Accurate linear dimming is compatible with PWM frequencies from 100 Hz to 5 kHz for PWM duty cycle down to 1%.". 2 - Maximum EN/PWM high time = 5us Does it mean that : - if my PWM frequency is 5kHz, the minimum duty cycle is 1% but if my PWM frequency is 1kHz, the minimum duty cycle can be 0.2% ? OR - the minimum duty cycle is 1% from 100Hz to 5kHz ? Thank you in advance.

The linearity is accurate down to 1% for the PWM. Notice at 5 us with 5 kHz PWM the duty cycle is 2.5% but the LEDs are effectively at 1% brightness when accounting for rise/fall times. This is at the most extreme operation where it’s already a bit non-linear.

You can run any timing as long as the THI and TLO specifications are obeyed, but the relationship may be non-linear below 1% duty cycle.
Answered by:
ON Semiconductor
2015-02-18 13:20:29.683