R1161N081A Datasheet, PDF (33/44 Pages) RICOH electronics devices division – 3-MODE 300mA LDO REGULATOR

TECHNICAL NOTES
VDD
OUT
C1
R1161xxxxx
GND SERIES
C2
CE
ECO
R1161x
When using these ICs, consider the following points:
1.Mounting on PCB
Make VDD and GND lines sufficient. If their impedance is high, noise pickup or unstable operation may result.
Connect a capacitor C1 with as much as 1.0µF capacitor between VDD and GND pin as close as possible.
Set external components, especially the output capacitor as close as possible to the ICs and make wiring as
short as possible.
2.Phase Compensation
In these ICs, phase compensation is made for securing stable operation even if the load current is varied. For
this purpose, be sure to use a 1.0PF more capacitor C2 with good frequency characteristics and ESR
(Equivalent Series Resistance).
Output Voltage
VOUT<1.0V
1.0V ^VOUT
Recommended Value of C2
1.0PF or more Tantalum Capacitor
1.0PF or more Ceramic Capacitor
(Note: When the additional ceramic capacitors are connected to the Output Pin with Output capacitor for phase
compensation, the operation might be unstable. Because of this, test these ICs with as same external
components as ones to be used on the PCB.)
If you use a tantalum type capacitor and ESR value of the capacitor is large, output might be unstable.
Evaluate your circuit with considering frequency characteristics.
Depending on the capacitor size, manufacturer, and part number, the bias characteristics and temperature
characteristics are different. Evaluate the circuit with actual using capacitors.
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