Datasheet

Datasheet

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TSZ02201-0F1F0C100240-1-2

© 2013 ROHM Co., Ltd. All rights reserved.

15.Feb.2016 Rev.006

www.rohm.com

TSZ22111・15・001

BD9486F

3.5.2 PWM Start Up 2 (Input STB Signal after Inputted PWM Signal)

Figure 33. PWM Start Up 2 (Input STB Signal after Inputted PWM Signal)

(*1)…REG50 starts up when STB=H.

(*2)…When REG50UVLO releases or PWM is inputted to the edge of PWM=L→H, SS charge starts and soft start period is

started. The GATE pulse outputs only during the corresponding PWM=H. And while the SS is less than 0.4V, the pulse

does not output. The pin SS continues charging in spite of the assertion of PWM or OVP level.

the set LED current flows. The abnormal detection of FBMAX starts to be monitored.

(*4)…As STB=L, the boost operation is stopped instantaneously (GATE=L, SS=L). (Discharge operation works in the state of

STB=L and REG50UVLO=H. Please refer to section 3.5.3)

(*5)…In this diagram, before the discharge period is completed, STB is changed to High again. As STB=H again, operation will

be the same as the timing of (*1).