PCMB065T-2R2MS datasheet(45/47 Pages) IRF

45 / 47 page

Dual output, 4A/Phase, Highly Integrated SupIRBuck

Single-Input Voltage, Synchronous Buck Regulator

IR3891

www.irf.com

May 08, 2013

STENCIL DESIGN



IR recommends that the larger Power or Land

Area pads are Solder Mask Defined (SMD).

This allows the underlying Copper traces to be

as large as possible, which helps in terms of

current carrying capability and device cooling

capability.



When using SMD pads, the underlying copper

traces should be at least 0.05mm larger (on

each edge) than the Solder Mask window, in

order to accommodate any layer to layer

misalignment. (i.e. 0.1mm in X & Y).



However, for the smaller Signal type leads

around the edge of the device, IR recommends

that these are Non Solder Mask Defined or

Copper Defined.



When using NSMD pads, the Solder Resist

Window should be larger than the Copper Pad

by at least 0.025mm on each edge, (i.e.

0.05mm in X & Y), in order to accommodate any

layer to layer misalignment.



Ensure that the solder resist in-between the

smaller signal lead areas are at least 0.15mm

wide, due to the high x/y aspect ratio of the

solder mask strip.

Figure 44: Stencil Pad Spacing (all dimensions in mm)

PCMB065T-2R2MS Datasheet(PDF) 45 Page - International Rectifier