Hi,
We are designing an Ethernet switch module using Microsemi chip VSC7422. With the same design circuits 5 modules has been assembled out of which first 4 modules are working fine with all ports 1Gbps links are up continuously. We are facing link issue in the 5th module alone. We have checked power rails and clock input to switch IC. Tried replacing the chip VSC7422. Everything is similar to first 4 modules. But the link is going up and down continuously for both 1Gbps and 100Mbps speed. Link is establishing in 10Mbps speed (Link LED is stable), but when tried to ping the switch most of the time request time out error is coming and randomly pinging is happening. We cannot suspect magnetics/transformer since all the ports of the switch are behaving same. When the 1Gbps Ethernet DATA-A-P & DATA-A-N is probed we are getting some pulses when the link is trying to establish, but again going to zero since the link is going down. Attached the signal waveform. We are unable to find out any issue and we are stuck where to debug.
Regards,
Hafiz
We are designing an Ethernet switch module using Microsemi chip VSC7422. With the same design circuits 5 modules has been assembled out of which first 4 modules are working fine with all ports 1Gbps links are up continuously. We are facing link issue in the 5th module alone. We have checked power rails and clock input to switch IC. Tried replacing the chip VSC7422. Everything is similar to first 4 modules. But the link is going up and down continuously for both 1Gbps and 100Mbps speed. Link is establishing in 10Mbps speed (Link LED is stable), but when tried to ping the switch most of the time request time out error is coming and randomly pinging is happening. We cannot suspect magnetics/transformer since all the ports of the switch are behaving same. When the 1Gbps Ethernet DATA-A-P & DATA-A-N is probed we are getting some pulses when the link is trying to establish, but again going to zero since the link is going down. Attached the signal waveform. We are unable to find out any issue and we are stuck where to debug.
Regards,
Hafiz
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