The PCF8581P can handle clock frequencies up to 2 MHz, but it's recommended to use a clock frequency of 1 MHz or less for reliable operation.
The PCF8581P can be reset by applying a low pulse to the RST pin. The pulse width should be at least 100 ns, and the RST pin should be pulled high after the pulse to allow the device to start operating normally.
The CE (Chip Enable) pin is used to enable or disable the PCF8581P. When CE is low, the device is enabled and can communicate with the microcontroller. When CE is high, the device is disabled and ignores any incoming data.
The PCF8581P can be configured for I2C or SMBus operation by setting the appropriate bits in the control register. For I2C operation, set bit 7 of the control register to 0. For SMBus operation, set bit 7 to 1.
The maximum capacitance that can be connected to the X1 and X2 pins is 22 pF. Exceeding this value may affect the oscillator's stability and frequency.