A Product Line of

Diodes Incorporated

PI2DPX2020

18

www.diodes.com

July 2022

Diodes Incorporated

PI2DPX2020

Document Number DS43506 Rev 5-2

RX2-

RX2+

RX1-

RX1+

TX2-

TX2+

TX1-

TX1+

4-PORT VECTOR

NETWORK ANALYZER

N52454

VICTIM INPUT

50Ω

50Ω

50Ω

50Ω

AGGRESSOR

SIGNAL

(0dBm)

VICTIM OUTPUT

Figure 7. NEXT Channel-isolation Test Configuration

JBERT (No Pre-emphasis)

Oscilloscope

Trace Card

Trace Card

Char Board(DUT)

Ch1

Ch2

Ch1

Ch2

SMA

cable

SMA

cable

SMA

cable

DUT

1) Trace card between TP1 and TP2 is designed to emulate 6-48” of FR4. Trace width -4 mils,100 differnetial impedance

2) All jitter is measured at a BER of 10-9

3) Residual jitter reects the total jitter measured at TP4 jitter minus TP1 jitter

4) VDD = 1.8V, RT = 50

5) The input signal from JBERT does not have any pre-emphasis.

TP1

TP2

TP3

TP4

Figure 8 Channel Measurement Setup

ML_TX_x_n

ML_TX_x_p

Source

Connector

Sink

Connector

Sink

Connector

Tx

Rx

50

50

Vbias_Tx

50

50

Vbias_Rx

Upstream device

Downstream device

ML_TX_x_n

ML_TX_x_p

ML_RX_x_n

ML_RX_x_p

ML_RX_x_n

ML_RX_x_p

Source

Connector

Tx

Rx

50

50

Vbias_Tx

50

50

Vbias_Rx

100k-1M

100k-1M

Figure 9. High-speed Channel Test Circuit