DP83869EVM: LED Jumper Settings on DP83869EVM

Hello, one more question. What voltage is AUX_IOVDD I don't see it in the schematics, but my eyes are old.

Thank you

Hello, thank you for responding to my message. What voltage is AUX_IOVDD I don't see it in the schematics.

Joe

The datasheet on page 47 shows LED with MODE 1 tied to VDD but there are different type of VDD pins on the device. Which VDD pin is the datasheet referring to?

Thank you

Hello, I have followed the Power Configuration as show on Figure 116 page 111 Three Supply Config.

I will configure the device to interface with an SFP+ module.

I have set LED_0 for Mode 0: Fiber auto-negotiation ON

I have set LED_1 for Mode 1: Config Pin 24 as Signal Detect Pin

I have connected LED_0 has shown on Figure 31 and connected LED_1 as shown in Figure 31.

How should I connected LED_2?

Can you explain why Figure 31 does not match how the jumpers are set on the EVM?

I believe there is a typo, I believe Mode 1 in the diagram is really Mode 0 and Mode 4 is really Mode 1 because the LED are 2 level only.

On the EVM they have a short to ground on Mode 0.

I must be missing something here.

Can you please help me.

Thank you

Joe

Hello, I wanted to attach my schematics for your review. I am strapping the pins for SFP mode:

MIB 38.pdf

Would you be so kind to look over this page for me please.

Thank you

Hi Joe,

IOVDD is 3.3V and is found in the power section of the schematic

That is correct Mode 1 and Mode 4 correspond to Mode 0 and Mode 1 since they are only two level straps. These straps should be the same pull up and pull down levels on the EVM. 

As for schematic review, please allow us 3-5 days to review schematics. 

Let me know if you have further questions.

Thanks,

Cecilia

Thank you very much for helping me find the voltage of IOVDD. I'll look again. Last, thank you for taking time to review my schematics.

Respectfully

Joe

Thanks Joe,

Will have my feedback in the next couple of days.

Cecilia

Hello, need your help again. My VDDIO is set for 1.8V so I can interface with an FPGA that has 1.8V I/O. If I change the LEDs to VDDIO the LEDs won't work because the Forward voltage is 2.1V. I cannot find a LED with a forward voltage that is lower that 1.8V.

If I change the VDDIO to 2.5V what signals do I need to go through a voltage translator? RMGII MDIO?

Thank you very much for your help.

Joe

Hello, I found an LED that has a Forward Voltage of 1.7V and a Current Test of 2mA. So it looks like I can change the LED strapping to VDDIO 1.8V and use a 50ohm resistor with the LEDS.

How does this look?

Thank you