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enter image description hereI have doubt regarding BGA pad creation for SN74CBTLV3245A LOW-VOLTAGE OCTAL FET BUS SWITCH. From attached picture, which should I have to take to create BGA pad type of both NSMD and SMD?

How to give values for SMD pad creation, NSMD pad creation? I know for NSMD pad creation we might take land pattern less than ball diameter, also we want to give soldermask opening for NSMD pad.

For example, I have a ball diameter of 0.5 mm, then I should take 0.4 nominal land pattern and soldermask opening is 0.627 — is this right? If it is wrong, then please guide me, and also explain SMD pad creation.

Here I attached one image, in this they given ball diameter (or land pattern?) for BGA. Kindly clear my doubt. If it is ball diameter then I have to take land pattern less than from given value. I am confused in this — is that ball diameter or ball land pattern? Kindly excuse me on my mistakes of language. i added one more picture here is this is lanpattern or not

enter image description here

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    \$\begingroup\$ Where is the image from? The figure caption/title usually states if it is a package drawing or a land pattern. I'm pretty sure it's the former though. \$\endgroup\$ – Justin Dec 7 '18 at 13:21
  • \$\begingroup\$ they didn't mention \$\endgroup\$ – Hari Babu Dec 7 '18 at 13:25
  • \$\begingroup\$ they just gave titile like plastic ball grid array .that's all \$\endgroup\$ – Hari Babu Dec 7 '18 at 13:26
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check this out for help BGA ball vs land patterns size. Seems like your ball size is 0.45 here and land patterns should be 0.35 +- 0.05.

http://processors.wiki.ti.com/index.php/General_hardware_design/BGA_PCB_design

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That part comes in so many package types - why not select one that has accessible pins, just for the ability to identify correct soldering? Personally I'd go with the 20-VQFN for a leadless package instead of the BGA.

QFN – RGY Tape and reel SN74CBTLV3245ARGYR CL245A Tube SN74CBTLV3245ADW

SOIC – DW CBTLV3245A Tape and reel SN74CBTLV3245ADWR

SSOP (QSOP) – DBQ Tape and reel SN74CBTLV3245ADBQR CBTLV3245A –40°C to 85°C

TSSOP – PW Tape and reel SN74CBTLV3245APWR CL245A

TVSOP – DGV Tape and reel SN74CBTLV3245ADGVR CL245A

VFBGA – GQN Tape and reel SN74CBTLV3245AGQNR CL245A

VFBGA – ZQN Tape and reel SN74CBTLV3245AZQNR CL245A

Also see Note 4 on Page 13, which refers to another drawing for tin-lead vs lead-free. http://www.ti.com/lit/ds/symlink/sn74cbtlv3245a.pdf

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  • \$\begingroup\$ This is the right answer. If you (OP) really need the space savings of the 4x4 mm sized BGA relative to the 4.5x5.5 mm QFN, you should be working closely with your assembly shop and getting their recommendation on the appropriate footprint for the BGA. \$\endgroup\$ – The Photon Dec 7 '18 at 18:08

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