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Power Good is built-in, internal circuitry as shown in Fig.9.1.1.
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Power Good pin becomes low state(0.3V max), when output becomes condition
such as overcurrent or output voltage ±12.5%(Typ) outside the set point value.
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The sink current of Power Good pin is 10mA max.
Fig. 9.1.1
Internal circuitry of
PGOOD
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When the input voltage is less than the start-up voltage, Power Good pin voltage is undefined.
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The voltage of Power Good is shown in Fig.9.1.2.
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Power Good cannot be used in the area of undefined.
Fig. 9.1.2
Voltage of
PGOOD
Fig.9.1.3
BRFS30-I
RC(2V/div)
Vin:12V
t0: 12ms(Max)
PGOOD
Vout:3.63V
Vout(1V/div)
load current:0A
Cin:22uFx4
Cout
:
300uF
PGOOD(5V/div)
5ms/div
Fig.9.1.4
BRFS50
RC(2V/div)
Vin:12V
t0: 9ms(Max)
PGOOD
Vout:2.0V
load current:0A
Vout(1V/div)
Cin:22uFx4
PGOOD(5V/div)
Cout
:
200uF
5ms/div
BRFS/BRDS 9-1
9.Power Good
t0
t0
Applications manual
For BRFS/BRDS series