[SOLVED] paralle vs series at high speed

Status
Not open for further replies.
1

1a2s3d4f

Member level 3
Joined
Oct 28, 2006
Messages
59
Helped
2
Reputation
4
Reaction score
2
Trophy points
1,288
Visit site
Activity points
1,785
Hi everyone,

Can someone explain to me the concept of serial and parallel.

For parallel
256 pcb traces needed to implement a full duplex, 10Gbps interface using two 128bit wide synchronous LVTTL buses running at 78MHz.

For Serial
The same data bandwidth can be implement using only 16 PCB trace by using 4 serial I/O, each operated at 2.5 Gbps.

Can some one please explain to me the math behind the two idea.

Thanks
 

It is not correct because f you want full duplex in serial data transfer you need to SPI protocol.
In this if you are running at 2.5gbps to transfer 128 bits you have to write a data of 16bytes for each byte it will take
1/clkspeed * 128.
So, pls check once again.
 

For the parallel:
256 PCB traces full duplex so you have 128 Trace in each direction.
128*78=10Gbps

For the serial:
16 PCB trace in total=> 8 wire in each direction => 4 serial lines, each line consist of 2 wires for differential signaling.
4*2.5=10 Gbps
 


Hi AdvaRes,

Thank you so much for clarify the concept. I would like to make sure that I understand the concept correctly, so the 4 serial line (2 pair of differential signal) are parallel with the other 4 serial IO devices. Regarding the 2.5Gbps on each IO, and each carried 4bit. This mean each IO operated at 625MHz (clk period of 1.6ns).
Please verify with me if I understand the concept correctly.

Thanks
 

Status
Not open for further replies.

Similar threads

Menu
Log in
Register
Cookies are required to use this site. You must accept them to continue using the site. Learn more…