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What type of control is this LED driver using?

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Flyback

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Hello,
I cannot tell from the datasheet ,what type of control this MXL10803 Buck LED driver is using....

MLX10803 LED driver datasheet:
https://www.melexis.com/Asset/MLX10803-IC-specification-DownloadLink-4840.aspx

from the block diagram on page 3 it looks like the two comparators set the peak and trough of the inductor current? (and thus the average output current)...thus it would be a hysteretic type control.?
...however, the pin descriptions on page 7 say that these two comparators are concerned with NTC feedback (temperature regulaton).
Also, the pin description page appears to indicate that the ROSC resistor sets the "off-time" (presumably the off time of the FET)...however, how does that link in with the two comparators?
Also, what is the equation that relates off-time and ROSC resistor value?, its not stated.

Does anyone understand this IC as such?

Is it a constant off time converter. If so, whats the maximum source sense resistor trip voltage?...so that we can be sure we don't saturate the inductor.
What makes the fet turn on? (is it the start of a new oscillator cycle?, or the end of some off time interval ?) ....then what makes the FET turn off?
 
The two comparators cannot possibly set the peak and trough currents, because when the MOSFET is turned off, the LED current does not go through the sense resistor.

Page 17 of the datasheet describes the switching strategy.
 
Seems like just an old current controlled buck regulator.
 
i think on page 17, when it says "half of a mximum value", I think it means half way between peak and trough, which is not half of a maximum value.....it also states that the fet turns off for between 9 to 16 pulses......but doesn't say how many pulses exactly...that's not much use.
 
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