Choosing an external 32.768kHz crystal. | Cypress Semiconductor
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Choosing an external 32.768kHz crystal.
How do I choose an External Crystal Oscillator as ILO for my PSoC 1 device ?
The internal ILO is designed to save power and hence it is not accurate. If the internal low speed oscillator does not provide the accuracy that your project requires, you have the option of using an external 32.768kHz watch crystal as the low speed oscillator for the PSoC.The input for the external clock is through P1. When choosing a crystal, you must make sure that the crystal has a maximum drive level of 1uW. An appropriate 32.768kHz crystal can be found on the Digikey website. Digikey Part Number: SE3202-ND