In the crystal oscillator industry, the 32.768kHz frequency is one of the most commonly used. It is a real-time clock (RTC) crystal oscillator that generates timing reference signals for precise one-second timekeeping, making it ubiquitous in the field of frequency components.
As we know, quartz crystal oscillators utilize the piezoelectric effect to produce stable oscillation signals, providing an accurate time reference for clock circuits. Like a tireless drummer, they consistently and steadily maintain a regular rhythm, where the frequency of this rhythm plays a decisive role in clock accuracy. In clock applications, this rhythm is set at 32.768kHz!
Why 32.768kHz?
Let's start with a simple calculation: 2^15 = 32768 = 32.768k
In the binary world of digital systems, there are only two possibilities: 0 and 1. Notably, 2 raised to the power of 15 equals 32,768.
When a 32.768kHz clock frequency undergoes 15 divisions, the resulting frequency is exactly 1Hz—equivalent to one second.
Thus, for every tick of the second hand, the quartz crystal vibrates 32,768 times, and the internal frequency divider in the clock performs 15 divisions to achieve precise timekeeping.