NJM2855
*Input Capacitor CIN
Input Capacitor CIN 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 CIN value (refer to conditions of ELECTRIC CHARACTERISTIC) or
larger and should connect between GND and VIN as shortest path as possible to avoid the problem.
*Output Capacitor CO
Output capacitor (CO) 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 CO 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 CO reduces output noise and ripple output, and also improves output
transient response when rapid load change.
Therefore, use the recommended CO value (refer to conditions of ELECTRIC CHARACTERISTIC) or
larger and should connect between GND and VOUT as shortest path as possible for stable operation
The recommended capacitance depends on the output voltage rank. Especially, low voltage regulator
requires larger CO 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 CO, 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.
Ver.2012-10-24
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