MAX15108 Datasheet, PDF (17/19 Pages) Maxim Integrated Products – High-Efficiency, 8A, Current-Mode Synchronous Step-Down Switching Regulator

High-Efficiency, 8A, Current-Mode
Synchronous Step-Down Switching Regulator
Layout Procedure
Careful PCB layout is critical to achieve clean and
stable operation. It is highly recommended to duplicate
the MAX15108 evaluation kit layout for optimum perfor-
mance. If deviation is necessary, follow these guidelines
for good PCB layout:
1) Connect input and output capacitors to the power
ground plane.
2) Place bypass capacitors as close to IN and the soft-
start capacitor as close to SS as possible.
3) Keep the high-current paths as short and wide as
possible. Keep the path of switching current short
and minimize the loop area formed by LX, the output
capacitors, and the input capacitors.
4) Connect IN, LX, and PGND separately to a large
copper area to help cool the IC to further improve
efficiency.
5) Ensure all feedback connections are short and
direct. Place the feedback resistors and compensa-
tion components as close as possible to the IC.
6) Route high-speed switching nodes (such as LX)
away from sensitive analog areas (such as FB,
COMP, SGND, and SS). See the MAX15108 EV Kit
layout for a tested layout example.
Typical Application Circuit
2.7V TO
5.5V
C_IN2
CIN2
22µF
22µF
SKIP
R_PULL
100kI
REXT_REF
1kI
C_SS
33nF
SKIP
LX
EN
PGND
IN
MAX15018
FB
INX
PGOOD
COMP
SS
L_OUT
33µH
C_EA2
100pF
OUTPUT
COUT1
47µF
COUT2
47µF
COUT1
0.1µF
R_EA
2.43kI
CEA
4700pF
R₁
8.06kI
R2
5.36kI
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