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TCA6416A: The output can't down to low level.

Part Number: TCA6416A


I have issue with P00 - P17 outputs.


  • The P00 used as output with 2.2KOhm Pull Up resistor.
  • Connected to 3.3v power supply 
  • The other circuit on this output disconnected for this test.  
  • In this setup the output can't down to low. After the command the output go down to 3.20v (from 3.27v)


  • If I removed Pull up resistor, the output go down correctly


  • The datasheet Iol / Ioh is 50 mA max. In my case it's 1.65 mA
  • I try change the pull up resistor to 10Kohm (0.33mA) - same results - can't down to low (3.20v).
  • I try same test on other output - same result.