Part Number: TMS320F28377D
Other Parts Discussed in Thread: TIDA-01606, , AMC1306M05
Tool/software:
Hi,
We are working with a TMS320F28377D on a ControlCard that is populated on a TIDA-01606 Evaluation Board.
We now have issues with the SDFM module not giving us correct measurement values when having maximum clock rate of 20MHz.
With a clock rate of 10MHz the measurement values are ok.
The following pictures show the clock (CH1, yellow) and data (CH2, red) signals @10MHz and @20MHz (persistent mode) directly measured at the ControlCard connector.
Both timing look the same in respect of the signal quality while switching the clock from low to high (rising edge). To me both timing run at the limit when consulting timing constraints from the datasheet.
So to me there is no change in the important timing between 10MHz and 20MHz clock rate.
Is there any other criteria beside the timing that can lead to this behaviour?
PS: Input qualification is 3-sample for clock and data (as recommended). SDFM is running in mode 0
PS2: Strange to me is that SDFM module expects data to change on the falling edge of clock and strobes for data on the rising edge of the clock. But as far as I know the TI modulators (like AMC1306M05 for example) changes data on the rising edge of clock. Therefore one always need to invert clock signal with GPxINV feature (?)
Any input is highly appreciated.
Best regards,
Patrick
