Ethernet compliance test

Ethernet Physical Layer compliance test is test if the physical layer meets the IEEE 802.3 standard.

Below are the items to be tested.

1. 100 Base-TX, UTP +Vout Differential Output Voltage

2. 100 Base-TX, UTP -Vout Differential Output Voltage

3. 100 Base-TX, UTP Signal Amplitude Symmetry

4. 100 Base-TX, +Vout Overshoot

5. 100 Base-TX, -Vout Overshoot

6. 100 Base-TX, UTP AOI Template

7. 100 Base-TX, AOI +Vout Rise Time

8. 100 Base-TX, AOI +Vout Fall Time

9. 100 Base-TX, AOI +Vout Rise/Fall Symmetry

10. 100 Base-TX, AOI -Vout Rise Time

11. 100 Base-TX, AOI -Vout Fall Time

12. 100 Base-TX, AOI -Vout Rise/Fall Symmetry

13. 100 Base-TX, AOI Overall Rise/Fall Symmetry

14. 100 Base-TX, Transmit Jitter

15. 100 Base-TX, Duty Cycle Distortion

16. Transmitter Return Loss

17. Receiver Return Loss

these test items for 100Base-T.

I will explain each test item by referring to the test example.

I used MSOS104A keysight.

Items 1 and 2 (+/-V output differential output voltage) measure the TX+/- voltage and make sure it is within 950 mV to 1.05 V

IEEE 802.3 (ANSI X3.263-1995, Section 9.1.2.2) define +/-V output differential output voltage 950mV <= Vout <= 1050mV

Item 3 Signal Amplitude Symmetry Check how symmetrical the amplitude of the TX+ signal and the TX-signal are.

Pass criteria are defined in IEEE Std. 802.3 (ANSI X3.263-1995, Section 9.1.4)

Item 4, 5 are test how much overshoot of TX+ and TX- occurs.

The calculated value of (Vpeak - Vout)/Vout*100 must not exceed 5.0%.

Vpeak represents the highest Vout measured at 8.0 ns from the 50% point of Vout.

Item 6 AOI Template is a test that verifies the overall signal stability of TX+ and TX- using eye diagrams defined in IEEE Std. 802.3 (ANSIX3.263-1995, Annex J).

Item 7, 8 +Vout Rise/Fall Time

Assuming that the change from the reference voltage (usually 0V) to +Vout is 100%, the test is to determine how long it took for the TX+ waveform to change from 10% to 90%.

The pass criterion is defined as 3.0ns<=t<=5.0ns in IEEE Std. 802.3 (ANSI X3.263-1995, Section 9.1.6).

Item 9

This is a test to check whether the difference between Min Max is less then 0.5ns the results obtained by measuring items 7 and 8 more than 100 times.

Item 10, 11 -Vout Rise/Fall Time

It's same with item 7, 8

Item 12

It's same with item 9

Item 13 This is a test to check whether the difference between Min Max is less then 0.5ns the results obtained by measuring items 7, 8, 10, and 11 more than 100 times.

Item 14 is to measure the total jitter to ensure that it is less than 1.4ns, which is the Pass criterion.

Item 15

Measure the Duty Cycle Distortion (DCD) Jitter to determine if it is measured below 0.5ns.

Item 16, 17 Measure the transmitter and receiver return loss to determine if it is in the Pass range.

The Ethernet compliance test is measured using a high-performance oscilloscope and measurement software, with measurement methods and pass criteria.

If you want to make a reliable product, I recommend that you conduct an Ethernet compliance test to ensure that your product meets the IEEE 802.3 standard.