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

3.5.6 FBMAX Detection

STB

GATE

FB

4.0V

① ②

CP

SS

3.7V

RT

SS

CP COUNTOR

NORMAL

SS

STATE

latch

off

STANDBY

STANDBY

・・・・・

・・・・・

(*1)

(*2)

(*3)

(*4)

(*5)

(*6)

(*7)

PWM

4.0V

3.0V

④

③

2.0V

REG50

Figure 37. FBMAX Detection

(*2)…During the soft start, it is not judged to the abnormal state even if the FB=H(FB>4.0V).

(*3)…When the PWM=H and FB=H, the abnormal counter doesn’t start immediately.

(*4)…The CP charge will start if the PWM=H and the FB=H detection continues up to 4 clocks of the GATE frequency. Once the

count starts, only FB level is monitored.

(*5)…When the FBMAX detection continues till the CP charge reaches 3.0V, IC will be latched off. The latch off interval can be

calculated by the external capacitance of CP pin. (Please refer to section 3.2.8.)

(*6)…The latch off state can be reset by the STB=L.

(*7)…It is normally started by PWM=L to H, in this figure.