LFXP20C-3FN256C Lattice, LFXP20C-3FN256C Datasheet - Page 392

• Manufacturer Part Number: LFXP20C-3FN256C
• Description: FPGA - Field Programmable Gate Array 19.7K LUTS 188 I/O
• Manufacturer: Lattice

Specifications of LFXP20C-3FN256C

• Number Of Programmable I/os: 188
• Data Ram Size: 405504
• Supply Voltage (max): 3.465 V
• Maximum Operating Temperature: + 90 C
• Minimum Operating Temperature: 0 C
• Mounting Style: SMD/SMT
• Supply Voltage (min): 1.71 V
• Package / Case: FPBGA-256
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

PCB Layout Recommendations
Lattice Semiconductor
for BGA Packages
PCB cross-sectioning is another method used to verify BGA and PCB quality and reliability. After a new process
has been developed or changed or when qualifying a new vendor, it is a good practice to get physical information
from the vendor on their BGA reflow. When trace/space and drill or laser tolerances are nearing their limits, board
yield can be as be as low as 50% for the bare board fab. Cross-sections give you a good idea if the process is cor-
rect but do not guarantee each batch or each board design will behave the same way due to layout dimensions,
thermal issues, flux/paste and alignment, etc.
Figure 14-17 shows a BGA cross-section that uses a non-soldermask over bare copper-defined pad. (NSMD) pad.
Figure 14-17. BGA Cross-Section
Figure 14-18 shows “offset” micro via stack routing between layers.
Figure 14-18. Cross-Section of Micro Vias
High-resolution video cameras are used for edge inspection to verify ball seating, distortion, solder wetting, flow,
contaminates, etc. Figure 14-19 is a video view of a side/edge shot looking at BGA balls soldered down to the isp-
MACH 4000ZE Pico Evaluation Board (www.latticesemi.com/4000ze-pico-kit), an FR4 4-layer PCB.
14-17