The PCF8593T/1118: NXP's Low-Power I2C Real-Time Clock/Calendar with On-Chip SRAM

In the realm of embedded systems and electronic design, reliable timekeeping is a fundamental requirement for a multitude of applications, from data logging and event timestamping to power management and automation. Addressing this need with a blend of precision, low power consumption, and integration, NXP Semiconductors' PCF8593T/1118 stands out as a robust and versatile solution. This integrated circuit is a low-power real-time clock/calendar (RTCC) that communicates via the ubiquitous I²C-bus serial interface, making it an ideal choice for space-constrained and power-sensitive designs.

At its core, the PCF8593T/1118 is engineered for accuracy and efficiency. It maintains a complete time representation, tracking seconds, minutes, hours, day, date, month, and year, with automatic leap year correction up to the year 2100. This ensures long-term reliability without requiring firmware intervention. A key feature of this device is its exceptionally low operating current, typically drawing just 15 µA at 3.0V. This makes it perfectly suited for battery-backed or portable applications where minimizing power drain is paramount for extending operational life.

Beyond its timekeeping capabilities, the PCF8593T/1118 integrates 256 x 8 bits of on-chip static RAM (SRAM). This integrated memory is a significant advantage, providing a dedicated space for storing critical system data, configuration settings, or event logs directly alongside the RTC. This eliminates the need for an external memory component, thereby reducing both the bill of materials (BOM) cost and the physical footprint on the printed circuit board (PCB).

The device's communication is handled through a serial I²C-bus interface, supporting a maximum frequency of 400 kHz. This standard two-wire interface simplifies connections to a host microcontroller, reducing the number of required GPIO pins and streamlining the overall system architecture. The PCF8593T/1118 also includes a programmable alarm function and a timer, which can be configured to generate interrupts for the microcontroller, enabling efficient event-driven system design.

For added reliability in mission-critical applications, the IC features a built-in power-on reset function and a watchdog timer. These safeguards help ensure the system starts in a known state and can recover from potential software failures. Furthermore, the device includes an oscillator stop detection function, which allows the microcontroller to verify the integrity of the clock data upon power-up.

In summary, the PCF8593T/1118 from NXP provides a comprehensive and highly integrated timing solution. Its combination of precise real-time clock functionality, ultra-low power consumption, and valuable on-chip SRAM offers designers a compact and reliable component that enhances system capabilities while optimizing power and space.

ICGOOODFIND: The PCF8593T/1118 is a highly integrated, low-power champion, perfectly merging a precise real-time clock with essential on-chip SRAM, making it a superior choice for battery-powered and space-constrained embedded systems.

Keywords:

1. Low-Power

2. Real-Time Clock/Calendar (RTCC)

3. I²C-bus Interface

4. On-Chip SRAM

5. Battery-Backed