SNLS144J June 2005 – January 2016 DS40MB200
PRODUCTION DATA.
Use at least a four-layer board with a power and ground plane. Closely coupled differential lines of 100 Ω are typically recommended for differential interconnect. The closely coupled lines help to ensure that coupled noise will appear as common-mode and thus will be rejected by the receivers. Information on the WQFN style package is provided in AN-1187 Leadless Leadframe Package (LLP) (SNOA401).
Stencil parameters such as aperture area ratio and the fabrication process have a significant impact on paste deposition. Inspection of the stencil prior to placement of the WQFN package is highly recommended to improve board assembly yields. If the via and aperture openings are not carefully monitored, the solder may flow unevenly through the DAP. Stencil parameters for aperture opening and via locations are shown in Figure 18. A layout example for the DS40MB200 DAP is shown in Figure 19, where 16 stencil openings are used for the DAP alongside nine vias to GND.
DEVICE | PIN COUNT | MKT DWG | PCB I/O PAD SIZE (mm) | PCB PITCH (mm) | PCB DAP SIZE (mm) | STENCIL I/O APERTURE (mm) | STENCIL DAP APERTURE (mm) | NUMBER OF DAP APERTURE OPENINGS |
GAP BETWEEN DAP APERTURE (Dim A mm) |
---|---|---|---|---|---|---|---|---|---|
DS40MB200 | 48 | SQA48A | 0.25 × 0.6 | 0.5 | 5.1 × 5.1 | 0.25 × 0.7 | 1.1 × 1.1 | 16 | 0.2 |