Abstract:3D simulations of a SATA connector is done using FDTD in EMPro, and then utilized in a signal integrity simulation in ADS.Due to faster data transfer rates required in today’s consumer electronics market, interconnect design, such as Serial Advanced Technology Attachment (SATA) to PCB interfaces, can no longer be ignored. Designers must include electromagnetic effects (coupling, crosstalk, etc.) of SATA connectors with board traces for accurate signal integrity analysis. In this example, a SATA connector is analyzed with EMPro. The EMPro simulation file is then exported as a design kit into ADS so that the connector data can be re-used for signal integrity analysis along with other circuit components in ADS.
Maintaining good signal quality throughout high-density and high-speed interconnects is the main objective of connector design. At multigigabit data rates, high speed interconnects must be accurately characterized.
Serial connectors have several advantages over parallel connectors such as faster switching and shorter signal rise time, which allow higher frequency bandwidth and high speed data transfer. Also, serial connectors use a fewer number of pins compared to parallel connectors; hence, the serial connectors are more compact in size.
Full-wave S-parameter analysis of SATA connectors is necessary to see the true performance of the connector at higher frequencies. RLC models are valid only when electrical length is less that λ/10 or the frequency is less than c0/(10*electrical length). At higher frequencies, transmission line and radiation effects become important. These details are not captured with an RLC model.
Figure 1: SATA connector basics
Figure 2: SATA pin configuration
FDTD simulations are run in EMPro, and the results are shown below. Figure 3 shows return loss and insertion loss for all the ports. Return loss is better than -10 dB up to 2 GHz. Ports 1,3,5 and 7 are input ports while ports 2,4,6 and 8 are outputs.
Figure 3: Simulation results for insertion loss and return loss
Figure 4 shows isolation between adjacent pots ( Port-1 & 3, Port 2 & 4 , Port-5 & 6 , Port-6 & 8). Port isolation is better than ~-12dB up to 2 GHz.
Figure 4: Simulation results for isolation of adjacent ports
In a complete SI design, one challenge is disparate and disconnected solvers that result in error prone data. Keysight’s integrated planar and full 3D EM tools provide a complete solution. Figure 5 shows how 3D and planar solver solutions are combined in a single SI analysis within ADS.
Figure 5: 3D and planer EM results are combined in an ADS signal integrity analysis
EMPro can give you early insight into possible connector / interconnect design problems enabling you to optimize signal transmission.