DS1644-120 – DALLAS

The DS1644-120 is a real-time clock (RTC) module integrating a time-of-day clock/calendar with a 32KB static random-access memory (SRAM) array, accessed via a parallel interface. The device operates as a peripheral to a microprocessor, providing non-volatile timekeeping and data storage. It is housed in a 28-pin dual in-line package (DIP) module, facilitating through-hole mounting. The RTC function tracks seconds, minutes, hours, day, date, month, and year, with automatic leap year compensation. Data retention is maintained by an embedded lithium battery, ensuring continuous operation and data preservation in the absence of external power. The -120 suffix denotes a maximum access time of 120ns for the SRAM component, influencing the overall system performance when accessing the memory. The parallel interface simplifies integration with a wide range of microcontrollers and embedded systems.