ACT4529M datasheet(10/15 Pages) ACTIVE-SEMI

10 / 15 page

ACT4529M

Rev 1, 23-Feb-17

Innovative PowerTM

- 10 -

www.active-semi.com

APPLICATIONS INFORMATION

PCB Layout Guidance

When laying out the printed circuit board, the

following checklist should be used to ensure proper

operation of the IC.

1) Arrange the power components to reduce the

AC loop size consisting of CIN, IN pin, SW pin,

the Schottky diode, and GND

2) Place input decoupling ceramic capacitor CIN as

close to VIN pin as possible. The GND side of

CIN must be placed as close as possible to to

power GND on the top layer. The traces should

be short and wide.

3) The high power loss components, e.g. the

controller, Schottky diode, and the inductor

should be placed carefully to make the thermal

spread evenly on the board.

4) Schottky anode pad and IC exposed pad

should be placed close to ground clips in CLA

applications

5) Use “Kelvin” or “4-wire” connection techniques

from the sense resistor pads directly to the CSP

and CSN pins. The CSP and CSN traces

should be in parallel to avoid interference.

6) Place multiple vias between top and bottom

GND planes for best heat dissipation and noise

immunity.

7) Use short traces connecting HSB-CHSB-SW

loop.

8) SW node is noisy, switching from VIN to GND.

Its size should be minimized and it should be

isolated away from the rest of circuit for good

EMI and low noise operation.

Example PCB Layout

ACT4529M Datasheet(PDF) 10 Page - Active-Semi, Inc