The maximum clock frequency that can be used with PCF8583T is 400 kHz. However, it's recommended to use a clock frequency of 100 kHz or less to ensure reliable operation.
The PCF8583T has a built-in power-on reset (POR) circuit that resets the device when the supply voltage (VCC) is below 1.5 V. To handle POR, ensure that the VCC rises slowly and monotonically during power-up, and wait for at least 100 ms after power-up before accessing the device.
The internal oscillator capacitor (OSC) pin is used to connect an external capacitor that helps to stabilize the internal oscillator frequency. A 10 nF to 100 nF capacitor is recommended to be connected between the OSC pin and VCC.
Yes, PCF8583T can be used as an RTC without a battery backup, but the time and date information will be lost when the power is turned off. If battery backup is not used, the device will reset to its default values when power is restored.
To ensure data integrity when writing to the PCF8583T's registers, use a write cycle that includes a start condition, a control byte, a register address, data bytes, and a stop condition. Also, ensure that the write cycle is completed before the next access to the device.
PCF8583T datasheet
by NXP Semiconductors
