IR3500VMPBF International Rectifier, IR3500VMPBF Datasheet - Page 33

• Manufacturer Part Number: IR3500VMPBF
• Description: The IR3500V Control IC combined with one or more xPhase3 Phase IC implement the control and MOSFET driver functions for a VR11.1 CPU VTT power supply.
• Manufacturer: International Rectifier

Specifications of IR3500VMPBF

• Package: 32-Lead MLPQ
• Circuit: X-Phase Control IC
• Switch Freq (khz): 250kHz to 1.5MHz
• Pbf: PbF Option Available

STENCIL DESIGN
• The stencil apertures for the lead lands should be approximately 80% of the area of the lead lands. Reducing the
• The stencil lead land apertures should therefore be shortened in length by 80% and centered on the lead land.
• The land pad aperture should be striped with 0.25mm wide openings and spaces to deposit approximately 50% area
• The maximum length and width of the land pad stencil aperture should be equal to the solder resist opening minus
amount of solder deposited will minimize the occurrence of lead shorts. Since for 0.5mm pitch devices the leads
are only 0.25mm wide, the stencil apertures should not be made narrower; openings in stencils < 0.25mm wide are
difficult to maintain repeatable solder release.
of solder on the center pad. If too much solder is deposited on the center pad the part will float and the lead lands
will be open.
an annular 0.2mm pull back to decrease the incidence of shorting the center land to the lead lands when the part is
pushed into the solder paste.
Page 33 of 34
July 28, 2008
IR3500V