DS1337C#T&R datasheet by Maxim Integrated Products

DS1337C#T&R Frequently Asked Questions (FAQs)

• What is the recommended power-up sequence for the DS1337?
  The recommended power-up sequence is to apply VCC first, followed by a valid clock signal, and then the RST pin can be released.
• How do I ensure that the DS1337 oscillator starts reliably?
  To ensure reliable oscillator start-up, a 1-10 kΩ resistor can be connected between the X1 pin and VCC, and a 10-22 pF capacitor can be connected between the X2 pin and GND.
• What is the purpose of the RST pin, and how do I use it?
  The RST pin is an active-low reset input that resets the DS1337 when pulled low. It can be used to reset the device during power-up or to recover from a fault condition.
• How do I configure the DS1337 for a 12-hour clock versus a 24-hour clock?
  The DS1337 can be configured for a 12-hour clock by setting the 12/24 hour bit (bit 6) in the hours register to 0, or for a 24-hour clock by setting it to 1.
• What is the purpose of the SQW/OUT pin, and how do I use it?
  The SQW/OUT pin can be configured to output a square wave at a frequency of 1 Hz to 4096 Hz, or as a general-purpose output pin. The frequency and mode are set by the SQWE and OUT bits in the control register.