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I am using ADS1278 chip. Analog inputs to this chip have been routed in differential pair manner. The differential pair inputs trace length is maximum 9 inch within the board from the ribbon connector to ADC chip. So .. Does this cause a voltage drop... My input voltage level is plus and minus 2.5V differential going to ADC.

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The minimum input impedance offered by the ADS1278 is 14kohm and if your traces were so long that they were ten ohms, the attenuation at DC would be 14,000/14,010 = 0.9993 or 6.2 milli decibels.

10 ohms of copper trace is many metres long BTW.

A 0.5mm wide trace on 1 oz copper is 9.71 ohms at 10m length. See this calculator

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  • \$\begingroup\$ Can you please help me suggesting that to achieve the max data rate of 52,734 SPS of the chip performance... what is the max trace length suggested to route the differential pairs of analog inputs from ribbon connector to ADS1278 analog input pins? \$\endgroup\$
    – Priya
    Jul 8 '15 at 8:49
  • \$\begingroup\$ Maximum data rate is irrelevant - what is the highest frequency within your signal that you wish to accurately measure? \$\endgroup\$
    – Andy aka
    Jul 8 '15 at 8:59
  • \$\begingroup\$ Highest Frequency is SCLK Signal-37MHz \$\endgroup\$
    – Priya
    Jul 8 '15 at 9:51
  • \$\begingroup\$ @Priya No, what is the highest frequency of the analogue signal that you wish to sample? \$\endgroup\$
    – Andy aka
    Jul 8 '15 at 9:53
  • \$\begingroup\$ Oh ok.. Highest frequency of the analogue signal is just Max 2kHz \$\endgroup\$
    – Priya
    Jul 8 '15 at 9:59

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