ꢀ TYPICAL APPLICATION AND TECHNICAL NOTES
1) Fixed Output Voltage Type
VOUT
VIN
Lx
AGND
MODE
VOUT
L
CIN
PGND
VDD
CE
LOAD
COUT
L
: 10µH LQH3C100K54(Murata)
COUT : 10µF ECSTOJX106R(Panasonic)
CIN : 10µF C3216JB0J106M(TDK)
2) Adjustable Output Voltage Type
L
VOUT
VIN
LX
AGND
MODE
VFB
CIN
PGND
R1
LOAD
Cb
VDD
CE
COUT
R
2
Rb
L:
10µH LQH3C100K54 (Murata)
COUT:
CIN:
10µF ECSTOJX106R (Panasonic)
10µF C3216JB0J106M (TDK)
Standard value of the sum of Divider Resistors, R1+R2 is as much as 100kΩ.
Cb value for phase compensation depends on values of L, C, and R1. Refer to the technical notes.
If a ceramic capacitor is used as an output capacitor, add 0.2Ω or more resistance to compensate the ESR of the
capacitor.
When you use these ICs, consider the following issues;
ꢀ Input same voltage into Power Supply pins, VIN and VDD. Set the same level as AGND and PGND.
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When you control the CE pin and MODE pin by another power supply, do not make its "H" level more than the
voltage level of VIN / VDD pin.
Set external components such as an inductor, CIN, COUT as close as possible to the IC, in particular, minimize the
wiring to VIN pin and PGND pin.
At stand by mode, (CE=”L”), the Lx output is Hi-Z, or both P-channel transistor and N-channel transistor of Lx pin
turn off.
Use an external capacitor COUT with a capacity of 10µF or more, and with good high frequency characteristics
such as tantalum capacitors.
At VFM mode, (MODE=”H”), Latch protection circuit does not operate.
Rev. 1.12
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RICOH [ RICOH ELECTRONICS DEVICES DIVISION ]
