SPRABN2A March   2019  – December 2019 AM3352 , AM3354 , AM3356 , AM3357 , AM3358 , AM3358-EP , AM3359

 

  1.   AM335x Schematic Checklist
    1.     Trademarks
    2. 1 Introduction
    3. 2 Recommendations Specific to AM335x
      1. 2.1  Unused Signals
      2. 2.2  SYSBOOT Configuration and Required Termination
      3. 2.3  System Issues
        1. 2.3.1 Pinmux
        2. 2.3.2 Pullups
        3. 2.3.3 General Debug
        4. 2.3.4 Warm Reset
        5. 2.3.5 Peripheral Clocking
      4. 2.4  Low-Power Considerations
      5. 2.5  Clocking
      6. 2.6  General DDR Guidelines
        1. 2.6.1 DDR2
        2. 2.6.2 DDR3
      7. 2.7  MultiMedia Card/ (MMC)
      8. 2.8  Inter-Integrated Circuit (I2C)
      9. 2.9  LCD
      10. 2.10 Power
      11. 2.11 Touchscreen
        1. 2.11.1 If ADC/Touchscreen is not Used
      12. 2.12 USB
        1. 2.12.1 If USB0 or USB1 is not Used
      13. 2.13 External Interrupt (EXTINTn)
      14. 2.14 Ethernet
    4. 3 References
  2.   Revision History

2.11 Touchscreen

  • Recommend adding 0ohm resistor to VDDA_ADC in case you need to add a filter for noise on the ADC.
  • Check out the sampling voltage must not exceed the voltage of reference. Otherwise, it will affect the whole TSC_ADC system. For example, if you add pull up to 3.0 V at the last four channel, this will lead to the abnormal work of the whole system, including the first four.
  • If the AM335x ADC/Touchscreen is not used, connect all TSC_ADC terminals (VREFP, VREFN, AIN[7:0], VDDA_ADC, and VSSA_ADC) to same ground as all VSS terminals.