R1172x

8

TYPICAL APPLICATION

(R1172xxx1B/D)

C1

R1172x

Series

CE

GND

C2

TECHNICAL NOTES

When using these ICs, consider the following points:

Phase Compensation

In these ICs, phase compensation is made for securing stable operation even if the load current is varied. For

this purpose, use a capacitor C2 with good frequency characteristics and ESR (Equivalent Series Resistance).

The recommendation value is as follows.

Output Voltage C2 recommendation value

Components Recommendation

Tantalum 4.7

µF or more

Ceramic 4.7

µF or more

Kyocera

Murata

Murata

4.7

µF (1608)

4.7

µF (1608)

10

µF (1608)

Part Number : CM105X5R475M06AB

Part Number : GRM188R60J475KE19B

Part Number : GRM188B30G106ME46B

Ceramic 4.7

µF or more

Kyocera

Murata

4.7

µF (thin 2012)

10

µF (2012)

Part Number : CT21X5R475M06AB

Part Number : GRM21BB30J106K

∗

∗

PCB Layout

Connect a capacitor C1 with a capacitance value as much as 4.7

close as possible to the pins.

Set external components, especially the output capacitor C2, as close as possible to the ICs, and make wiring

as short as possible.

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.