IR3531A datasheet(36/39 Pages) IRF

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4+1 Phase Dual Output Control IC

IR3531A

March 22, 2012 | FINAL | V1.11

SOLDER RESIST

 The solder resist should be pulled away from

the metal lead lands by a minimum of 0.06mm.

The solder resist misalignment is a maximum

of 0.05mm and it is recommended that the 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.

 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 land pad should be Solder Mask Defined (SMD),

with a minimum overlap of the solder resist onto the

copper of 0.06mm to accommodate solder resist

miss-alignment. In 0.5mm pitch cases it is allowable

to have the solder resist opening for the land pad to

be smaller than the part pad.

 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.

 The vias in the large center pad should be tented or

plugged from bottom board side with solder resist.

Figure 20: Solder Resist

* Contact International Rectifier to receive an electronic PCB Library file in your preferred format.

IR3531A Datasheet(PDF) 36 Page - International Rectifier