MAX15021ATI Datasheet, PDF (20/24 Pages) Maxim Integrated Products – Dual, 4A/2A, 4MHz, Step-Down DC-DC Regulator

MAX15021
Dual, 4A/2A, 4MHz, Step-Down DC-DC
Regulator with Tracking/Sequencing Capability
Applications Information
PCB Layout Guidelines
Careful PCB layout is critical to achieve clean and sta-
ble operation. Follow these guidelines for good PCB
layout:
1) Place decoupling capacitors as close as possible to
the IC pins.
2) Keep SGND and PGND isolated and connect them
at one single point close to the negative terminal of
the input filter capacitor.
3) Route high-speed switching nodes away from sensi-
tive analog areas (FB_, COMP_, and EN_).
4) Distribute the power components evenly across the
board for proper heat dissipation.
5) Ensure timing resistor and all feedback connections
are short and direct. Place feedback resistors as
close as possible to the IC.
6) Place the bank of the output capacitors close to the
load.
7) Connect the MAX15021 exposed pad to a large
copper plane to maximize its power dissipation
capability. Connect the exposed pad to SGND
plane. Do not connect the exposed pad to the
SGND pin directly underneath the IC.
8) Use 2oz. copper to keep trace inductance and
resistance to a minimum. Thin copper PCBs can
compromise efficiency since high currents are
involved in the application. Also thicker copper con-
ducts heat more effectively, thereby reducing ther-
mal impedance.
9) A reference PCB layout included in the MAX15021
Evaluation Kit is also provided to further aid layout.
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Maxim Integrated