Datasheet

ADP2121
Rev. B | Page 19 of 20
PCB LAYOUT GUIDELINES
07407-043
VINMODE
ADP2121
EN CIN
GND
COUT
L1
SW
VOUT
3.4mm
2.5mm
Figure 56. Solution Size with a 1008 Inductor
2.0mm
07407-044
VINMODE
ADP2121
EN CIN
GND
COUT
L1
SW
VOUT
2.65mm
Figure 57. Solution Size with a 0805 Inductor
07407-045
1.8mm
2.2mm
COUT
VIN
MODE
ADP2121
EN CIN
GND
L1
SW
VOUT
Figure 58. Solution Size with a 0603 Inductor
For high efficiency, good regulation, and stability with the
ADP2121, a well-designed PCB is required.
Use the following guidelines when designing PCBs:
• Keep the low ESR input capacitor, CIN, close to VIN
and GND.
• Keep high current traces as short and as wide as possible.
• Avoid routing high impedance traces near any node
connected to SW or near the inductor to prevent radiated
noise injection.
• Keep the low ESR output capacitor, COUT, close to FB and
GND of the ADP2121. Long trace lengths from the part to
the output capacitor add series inductance and may cause
instability or increased ripple.