DS12885Q+ datasheet by Maxim Integrated Products

DS12885Q+ Frequently Asked Questions (FAQs)

• What is the recommended power-up sequence for the DS12885Q+?
  The recommended power-up sequence is to apply VCC first, followed by VBAT. This ensures that the internal voltage regulators are properly initialized.
• How do I ensure that the DS12885Q+ oscillator starts reliably?
  To ensure reliable oscillator startup, make sure that the crystal oscillator circuit is properly designed and laid out, and that the crystal is of high quality. Also, ensure that the VCC supply is stable and within the recommended range.
• What is the maximum allowed capacitance on the VBAT pin?
  The maximum allowed capacitance on the VBAT pin is 10uF. Exceeding this value may affect the device's ability to properly switch between battery and VCC power sources.
• How do I handle the case where the battery is completely drained?
  In the event that the battery is completely drained, the DS12885Q+ will automatically switch to VCC power when it is available. However, it is recommended to implement a power-fail detect circuit to alert the system of a low-battery condition and take appropriate action.
• What is the purpose of the RST pin, and how should it be used?
  The RST pin is an active-low reset input that can be used to reset the device. It should be connected to a pull-up resistor and a capacitor to ensure proper reset operation. The RST pin can also be used to reset the device in response to a power-fail condition.