R1215D Datasheet, PDF (8/22 Pages) RICOH electronics devices division – STEP-UP DC/DC CONTOLLER

R1215D
TYPICAL APPLICATIONS AND TECHNICAL NOTES
Inductor
Diode
VOUT
C1
C2
C6
R5
VIN
EXT
DELAY
VFB
R3
NMOS
C4
GND AMPOUT
VREFOUT DTC
C5 R4
R6
C7
R1
C3
R2
Inductor
NMOS
Diode
C1
C2
C3
C4
C5
C6
C7
LDR655312T-100 (TDK)
CPH6415 (Sanyo)
CRS02 (Toshiba)
1.0µF
R1
1.0µF
R2
15µF
R3
1000pF
R4
2200pF
R5
1.0µF
R6
1.0µF
160kΩ
20k Ω
1k Ω
4.7k Ω
68k Ω
240k Ω
Use a 1µF or more capacitance value of bypass capacitor between VIN pin and GND, C1 as shown in the
typical application above. Connect the capacitor as short as possible to the IC.
• In terms of the capacitor for setting delay time of the latch protection, C2 is shown in typical application above.
Latch delay time depends on this C2 value. Refer to the Latch Protection Operation Timing Chart.
Set the C2 GND as close as possible to the IC GND.
• Connect a 1µF or more value of capacitor between VOUT and GND, C3 as shown in typical application above.
(10µF to 22µF is the capacitance recommendation range.) If the operation of the composed DC/DC converter
may be unstable, use a tantalum type capacitor instead of ceramic type
• Connect a capacitor between VREFOUT and GND, C6 as shown in typical application of the previous page.
The capacitance value of C6 is between 0.1µF and 1.0µF.
8