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

3.5.4 Soft Start Function

STB

3.0V

2.8V

PWM

OVP

SS

2.7V

3.0V

7.2V

7.5V

UVLO

VCCUVLO

REG50UVLO

(*1)

(*2)(*3)

(*4)

(*5)

(*6)

(*7)

2.3V

2.6V

RT

2.0V

4clk

Figure 35. Soft Start Function

(*1)…The SS pin charge does not start by just STB=H. PWM=H is required to start the soft start. In the low SS voltage, the

GATE pin duty depends on the SS voltage. And while the SS is less than 0.4V, the pulse does not output.

(*2)…By the time STB=L, the SS pin is discharged immediately. As REG50UVLO=H, RT is still High.

(*3)…As the STB recovered to STB=H, The SS charge starts immediately by the logic PWM=H in this chart.

(*4)…The SS pin is discharged immediately by the UVLO=L.

(*5)…The SS pin is discharged immediately by the VCCUVLO=L.

(*6)…The SS pin is discharged immediately by the REG50UVLO=L.

(*7)…The SS pin is not discharged by the abnormal detection of the latch off type such as OVP until the latch off.