Other Parts Discussed in Thread: ADS1298
I had asked this question on the forum previously and I had concluded from the discussion there that the problem is with my PCB design and I changed it to look exactly like the ADS1298 ECGFE_PDK board.
I am still facing these issues:
1. DRDY Pin stops toggling after 10 or 20 times (the number of times it toggles before stopping is not constant but it is under 50).
2. If it doesn't stop toggling, then Data should come right?!.. well I keep receiving 0 (Which I conclude, as the ADS stops sending any data at all, that my controller interprets it as 0).
3. I read about internally generated test signals in ADS, and that receiving them validates that the signal path is clear. So I tried to test it (I think checking internal test signals is irrelevant to how or whether ECG leads are connected). IF that is correct, I should get 1Hz square waves. I don't get them. Problems 1 & 2 prevail.
SPI communication works, Register Reads and Writes work, Tried and Tested.
I am using STM32L04 as my MCU and DRDY pin is configured as Input with pull up resistors enabled.
Voltage at VCAP1 pin is 1.1V. So that is checked and out of the way.
I have spent a lot of time and resources trying to recreate the board but it still isn't working so I am out of wits.
I have concluded that the Digital part of the ADS works fine, but the ADC part doesnt work at all. Is this conclusion correct given the symptoms?
I have inserted the images of the front:
And the back of the board:
This is the schematic and layout files:
Thanks for Help,
Ninad Gandhi.
