Technical Note

11/28

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2011.06 - Rev.B

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BD6150MUV

・

soft start of Over current limit for application

When the capacitor of OCPSET is set as figure, over current limit can become setting value slowly.

This effect is same as internal soft start.

When you want to reduce peak current than internal soft start on start up, this way is effective.

But, this action repeat when the timing that PWMPOW change L to H, so to do PWM control with PWMPOW terminal,

rise time of over current limit must be set into Hi time of PWM control, and please don’t connect the capacitor.

Show example of rising wave form with OCPSET 330pF.

Fig.25 Rising wave form with VBAT=5V, 6parallel 10serial 20mA/ch, OCPSET=68kΩ,330pF

Current Sence

OCPSET

+

-

Detect

R(OCPSET)

1.5A

VOUT

PWMPOW

Coil current

OCPSET

36m