ADS42LB69EVM: TIMED_OUT_ERROR

Spilios,

What is the status of the LED's on the TSW1400EVM after you have loaded the firmware and applied a clock to J3 of the ADS42LB69EVM? All status LED's from D2-D9 should be on except for D6. If there is an issue with your input clock, D5 will be off as well.

What config file did you load for the ADC?

1V pp should be fine for the clock. Make sure the 5V supply for the TSW1400 can provide at least 3A. 

Regards,

Jim

Hello Jim,

Indeed the D5 is off as you mentioned. I am using an RF signal generator as clock. The signal has 1Vpp (checked also through an oscilloscope) and a frequency of 245.76MHz.

I have tried both configurations.

Thanks,

Spilios

Spillios,

Can you verify the FPGA on the TSW1400 is getting the clock from the ADC by probing R54 on the back side of the TSW1400 under the FPGA, as shown in the attached drawing? This is a 100 Ohm termination resistor that is connected across the P and N clock inputs.

Regards,

Jim

The ADC is an evaluation board and I just plugged it into the TSW1400. The clock signal is connected to the CLK_INM of the ADC. 

I don't know what to check to verify that and also the image has very low resolution I cannot really distinguish anything.

With both boards plugged in and a clock provided to the ADC EVM and the ADS42LB69EVM programmed, you will need to flip the setup upside down and try to verify if a clock is present across R54 on the TSW1400EVM. This is the data output clock the ADC sends to the FPGA to be used to capture the data. If this clock is present, LED D5 would be ON.

Regards,

Jim

Hello Jim,

I test the R54 resistor and no signal was detected. Can toy propose any further tests I can perform?

Thanks,

Spilios

Hello Jim,

following my previous comment could it be possible to measure the clock output from the 56 and 58 pin of the LVDS connector of the ADC without having it plugged in the TSW1400 board?

Thanks,

Spilios

Spilios.

Yes, you can try these two pins. You could also try pins 56 and 57 on the ADC. Another interesting test would be to monitor the current of the 5V supply connected to the ADC EVM and see if it goes down when you turn off or disconnect the clock source going to the board.

Regards,

Jim

According to the user guide of the ADS42LB49EVM the ADC should be connected to a power source of 3.3 V (page 8 of the user guide). Using this voltage, the current is close to 0.007 A and does not change. The current of the TSW1400EVM increases when the configuration is loaded on the ADC. So the pins in the ADC that carries the clock signal are the 56 and 57?

Thanks,

Spilios

You are correct, 3.3V. 

See attached schematic for pinout info.

8270.ADS42LB69EVM-SCH_A.pdf

Hi Jim, 

I measured the pins' signal and recorded it for two different clock signals. Both signals were sinusoidal with 1 Vpp and 150 MHz, and 200 MHz frequencies. The recorded signals are presented in the following diagrams.

Thanks,

Spilios

 Where was this measured at? Can you try a different signal generator? 

At the 56 and 58 pins. The signal of the RF generator has been tested with an oscilloscope. No I don't have a different generator. Although, in a previous communication with TI technical support assured me that the RF generator that I am using will be.

Is there anything else I should test?

Thanks,

Spilios

Please send back the register settings that are loaded into the ADC. Are you pressing the ADC board reset after power and clock is applied?

Is you scope shot with the TSW1400 connected or not? If it is connected, you may be seeing reflections. This is why I would like you to probe R54 on the TSW1400. If the TSW1400 was not connected, these traces are unterminated and the output will also appear incorrect.