DS8817A Datasheet, PDF (20/21 Pages) Richtek Technology Corporation – Dual-Phase PWM Controller with PWM-VID Reference

RT8817A
Layout Considerations
Layout is very important in high frequency switching converter design. If designed improperly, the PCB could radiate
excessive noise and contribute to the converter instability. Following layout guidelines must be considered before
starting a layout for RT8817A.
 Place the RC filter as close as possible to the PVCC pin.
 Keep current limit setting network as close as possible to the IC. Routing of the network should avoid coupling to high
voltage switching node.
 Connections from the drivers to the respective gate of the high-side or the low-side MOSFET should be as short as
possible to reduce stray inductance.
 All sensitive analog traces and components such as VSNS, RGND, EN, PSI, VID, PGOOD, VREF, TON, REFADJ,
REFIN and OCSET/SS should be placed away from high voltage switching nodes such as PHASE, LGATE, UGATE,
or BOOT nodes to avoid coupling. Use internal layer(s) as ground plane(s) and shield the feedback trace from power
traces and components.
 Power sections should connect directly to ground plane(s) using multiple vias as required for current handling (including
the chip power ground connections). Power components should be placed to minimize loops and reduce losses.
Copyright ©2016 Richtek Technology Corporation. All rights reserved.
www.richtek.com
20
is a registered trademark of Richtek Technology Corporation.
DS8817A-00 September 2016