Crosstalk and EMI Reduction using enhanced Guard Trace Technique

Client system design space is becoming aggressive every year and all these aggressive designs have more signal traces routed in any given area; whether in microstrip or in strip line. This is true for system mother board level as well as package substrate level. Guarding high speed signals by a co-planar grounded trace is the traditional way of reducing the crosstalk and EMI. This grounded trace will usually run along with the high-speed signal throughout the channel. But as the speeds are going higher, most of the interface margins are still limited by crosstalk and the proposed “Elevated guard trace technique” can further reduce crosstalk and EMI in order to increase overall system performance. This innovative technique of Guard trace can be utilized in microstrip layers routed with high speed signals to minimize EMI emissions significantly.