PCF8563P/F4 datasheet by NXP Semiconductors

PCF8563P/F4 Frequently Asked Questions (FAQs)

• What is the recommended power-on reset (POR) circuit for PCF8563P/F4?
  A simple RC circuit with a 1 kΩ resistor and a 10 μF capacitor is recommended to ensure a clean power-on reset. This circuit should be connected between VCC and GND.
• How do I ensure that the PCF8563P/F4 oscillator starts up reliably?
  To ensure reliable oscillator startup, a 1 kΩ to 10 kΩ pull-up resistor should be connected between the XIN pin and VCC. Additionally, the XIN pin should be decoupled with a 10 nF to 100 nF capacitor to GND.
• What is the maximum clock frequency that can be used with the PCF8563P/F4?
  The maximum clock frequency that can be used with the PCF8563P/F4 is 32.768 kHz. This is the typical frequency used for real-time clock applications.
• How do I handle the battery switchover function in the PCF8563P/F4?
  The battery switchover function can be handled by connecting the VBAT pin to a battery or a supercapacitor. When the main power supply (VCC) fails, the device will automatically switch to the battery or supercapacitor. The switchover threshold is typically set to around 1.5 V.
• What is the purpose of the CLKOUT pin in the PCF8563P/F4?
  The CLKOUT pin provides a 32.768 kHz clock output that can be used as a clock source for other devices in the system. This pin can be used to synchronize other devices or to drive a microcontroller's clock input.