BD4140HFV

Technical Note

4/8

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2009.04 - Rev.B

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<VCC starting>

①

When VCC is below the minimum operation voltage, PGOOD pin will be at H level.

(The meaning of the minimum operation voltage is : When the starting of VCC, PGOOD output voltage become

within 10% of VCC voltage, and the value will be around 0.8VTYP(RPGOOD=100kΩ) and 1.0VTYP(RPGOOD=10kΩ).

But note that this value is reference.)

②

If VCC value exceeds the minimum operation voltage, by the VCC reached UVLO cancellation voltage (2.5V TYP),

PGOOD output become at L level.

③

If VCC exceeds UVLO cancellation voltage, when the input voltage of IN pin is over the detected voltage, PGOOD pin

will be at H level, and when the input voltage of IN pin is below the detected voltage, PGOOD pin will be at L level.

(PGOOD=OK)

(PGOOD=NG)

VCC

PGOOD

DLY

VCC

GND

IN

VCC

PGOOD

DLY

VCC

GND

IN

ｔ

0

1(0.8)

UVLO Cancellation voltage

ｔ

2.5

5

0

ｔ

ｔ

5

1(0.8)