NJU7771/72/73/74/75/76
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Ver.2013-04-05
*Input Capacitor C
IN
Input Capacitor C
IN
is required to prevent oscillation and reduce power supply ripple for applications when high
power supply impedance or a long power supply line.
Therefore, use the recommended C
IN
value (refer to conditions of ELECTRIC CHARACTERISTIC) or larger and
should connect between GND and V
IN
as shortest path as possible to avoid the problem.
*Output Capacitor C
O
Output capacitor (C
O
) will be required for a phase compensation of the internal error amplifier.
The capacitance and the equivalent series resistance (ESR) influence to stable operation of the regulator.
Use of a smaller C
O
may cause excess output noise or oscillation of the regulator due to lack of the phase
compensation.
On the other hand, Use of a larger C
O
reduces output noise and ripple output, and also improves output
transient response when rapid load change.
Therefore, use the recommended C
O
value (refer to conditions of ELECTRIC CHARACTERISTIC) or larger
and should connect between GND and V
OUT
as shortest path as possible for stable operation
The recommended capacitance depends on the output voltage rank. Especially, low voltage regulator requires larger
C
O
value.
In addition, you should consider varied characteristics of capacitor (a frequency characteristic, a temperature
characteristic, a DC bias characteristic and so on) and unevenness peculiar to a capacitor supplier enough.
When selecting C
O,
recommend that have withstand voltage margin against output voltage and superior temperature
characteristic though this product is designed stability works with wide range ESR of capacitor including low ESR
products.
