AR1100 - Can I use an oscillator in place of the crystal?

You can use a clock oscillator module in place of the crystal. The input connection is to OSC1. The input should meet the VIL and VIH levels. OSC2 is not used: do not connect it and do not ground it.

VIH and VIL levels for the TX and RX inputs at both 3.3 V and 5 V supply are:

  • VIL = 0.2 x VDD
  • VIH = 0.8 x VDD

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