July 16, 2014 | DATASHEET V3.3

19

IR3553

40A Integrated PowIRstage®

SOLDER RESIST

 The solder resist should be pulled away from

the metal lead lands by a minimum of 0.06mm.

The solder resist miss-alignment is a maximum

of 0.05mm and it is recommended that the low

power signal lead lands are all Non Solder Mask

Defined (NSMD). Therefore pulling the S/R

0.06mm will always ensure NSMD pads.

 The minimum solder resist width is 0.13mm

typical.

 At the inside corner of the solder resist where

the lead land groups meet, it is recommended

to provide a fillet so a solder resist width of ≥

0.17mm remains.

 The dimensions of power land pads, VIN, PGND,

TGND and SW, are Non Solder Mask Defined

(NSMD). The equivalent PCB layout becomes

Solder Mask Defined (SMD) after power shape

routing.

 Ensure that the solder resist in-between the lead

lands and the pad land is ≥ 0.15mm due to the

high aspect ratio of the solder resist strip

separating the lead lands from the pad land.

Figure 34: Solder resist

* Contact International Rectifier to receive an electronic PCB Library file in Cadence Allegro or CAD DXF/DWG format.