Datasheet

Data Sheet
BP5220A/BP5221A/BP5222A
Application Example 3 : Output voltage adjustment
(1) When reducing the output voltage
VR value setting equations (The output voltage after adjustment is denoted by Vo.)
(1) When reducing the output voltage
BP5220A / BP5221A
BP5222A
(2) When increasing the output voltage
BP5220A / BP5221A
BP5222A
To maximize performance we recommended the output voltage be
adjusted within ±20% of the output voltage rating. When the output voltage is increased by 20%, for
instance, the minimum input voltage is also increased by 20%.
(Example : When the output voltage is changed from 5V to 6V in the BP5220A, the minimum input voltage
is charged from 8V to 9.6V)
(2) When increasing the output voltage
Fig.7
Fig.9
Application Example 4 : Slow start
The slow start circuit mitigates the pulse load on the internal switching transistor when input voltage is applied,
and increases the output voltage gradually by starting the switching operation slowly.
This application is useful for preventing malfunction of an external protection circuit due to rush current,
and can serve as a countermeasure against operation outside the safe operation range.
C1 is a slow-start capacitor for mitigating excessive rush current that flows into the module when the switch is
turned on.
Vi
9 7654321
VR
BP5220A / BP5221A / BP5222A
V
O
+
+
Be sure to use
fuse for safety.
9 7654321
470 F
VR
VO
BP5220A / BP5221A / BP5222A
+
Fig.8
100 F
Vi
+
Be sure to use
fuse for safety.
9 7654321
VO
470 F
100k
C1
10
F
Vi
24V
470k
BP5220A / BP5221A / BP5222A
2SC1740R
100 F
+
+
+
Be sure to use
fuse for safety.
5/7
2010.03 - Rev. B
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