ADA4356ABCZ datasheet(59/61 Pages) AD

59 / 61 page

Data Sheet

ADA4356

analog.com

Rev. 0

59 of 61

PCB Design Tips

Signal Integrity Recommendations

Place the photodiode signal source as close as possible to the ADA4356 input to minimize trace length and associated

parasitic capacitance. Clear away all ground layers directly underneath the input trace to reduce parasitics even

further. Additionally, match the lengths of all LVDS lines (DCON, DCOP, FCON, FCOP, D0AN, D0AP, D1AN, and D1AP)

to eliminate potential timing issues.

Thermal Design Recommendations

The ADA4356 uses multiple VCC and GND balls to facilitate the internal power and grounding requirements. All of

these balls must be connected for proper electrical connectivity within the module. Additionally, the PCB connection

of the multiple VCC and GND balls is an integral part of the thermal design. All the ADA4356 VCC and GND balls must

be connected to a PCB copper plane with the lowest thermal resistance possible. To achieve the best thermal

performance, these planes must have as many thermal vias as practical to provide the lowest possible thermally

resistive path for heat dissipation to flow through the bottom of the PCB. Solder fill or plug these vias.

Surface-Mount Design

Table 23 is provided as an aid to PCB design to accommodate CSP_BGA style surface-mount packages. For industry-

standard design recommendations, refer to IPC-7351, Generic Requirements for Surface Mount Design and Land

Pattern Standard.

Table 23. CSP_BGA Data for Use with Surface-Mount Design

PACKAGE

BALL ATTACH TYPE

SOLDER MASK OPENING

BALL PAD SIZE

84-Ball CSP_BGA (BC-84-4)

Solder mask defined

0.35mm diameter

0.40mm diameter

ADA4356ABCZ Datasheet(PDF) 59 Page - Analog Devices