Core Dialogue | Embedded Timing Revolution! Why CBM13S38 Industrial RTC is the Preferred Choice

As the "time hub" of embedded devices, Real-Time Clock (RTC) chips are essential components ensuring data timing accuracy and device controllability. In today's rapidly evolving landscape of industrial IoT, medical electronics, and smart consumer terminals, their reliability, low power consumption, and integration level have become critical factors determining product competitiveness. However, traditional RTC chips face three core challenges: timing inaccuracies in extreme environments, insufficient battery endurance for powered devices, and risk of critical data loss during power outages, making them inadequate for the stringent requirements of high-end embedded systems.

Corebai's CBM13S38 series serial RTC chips, featuring industrial-grade reliability, ultra-low power consumption, and full-function integration, precisely address these pain points, making them the go-to solution for time management in industrial IoT, medical devices, and high-end consumer electronics.

Nanoscale Low Power Design: After testing the current characteristics in a constant temperature and humidity environment, when the CBM13S38 oscillates on and the square wave output is off, the standby current is as low as 800-1200nA; in standby power mode (data retention), the current is only 10-100nA; in active operation, the typical current of the 1.8V version is only 75μA,3.3V of the typical current of the 120μA version, and even under high voltage conditions of 5.5V, the maximum current is still controlled within 325μA.

Industrial-grade wide temperature and intelligent power protection: The chip operates stably within a temperature range of-40°C to +85°C, with storage temperatures reaching-55°C to +125°C, meeting the requirements for extreme temperature variations. The built-in power failure detection circuit responds quickly, automatically switching to the backup power supply (VBAT compatible with 1.3～3.7V) when the main power supply (VCC) drops below the fault voltage (VPF) (1.8V version tested at 1.51～1.71V,3.3V version 2.70～2.97V). Additionally, the oscillator stop flag (OSF) accurately monitors the clock operation status, providing timely feedback on data validity in case of power anomalies.

Power failure data integrity: Field tests demonstrate that the chip's 56-byte NVSRAM (address range 08H~3FH) maintains I²C bus-level read/write speeds. When the main power fails, VBAT ensures uninterrupted operation, preserving critical data including transaction records and measurement parameters without corruption or loss.

Multiple voltage and multiple package adaptation, reducing design costs: The CBM13S38 power supply voltage covers 1.71V～5.5V,1.8V,3.0V,3.3V versions and can accurately match different power systems such as low power, normal, and high voltage; the package provides three specifications: SOP-8, SOP-16, and MSOP-8; the I²C interface supports a maximum clock frequency of 400KHz in fast mode, and there is no compatibility issue with mainstream chips such as STM32 and MCU, without additional level conversion.

Programmable square wave output: The CBM13S38 can output 1Hz, 4.096kHz, 8.192kHz, 32.768kHz of these four square wave frequencies stably, and the switch can be achieved by controlling the SQWE bit (square wave enable) and RS1/RS0 bit (rate selection) in the control register (07H). Its open drain output is compatible with 3.3V/5V system, and the duty cycle error of the output waveform is less than 5%.

2. Typical application scenarios: Meeting core requirements across multiple industries

Industrial IoT and metering solutions: Devices including electricity meters, water meters, temperature monitors, and vending machines. Featuring industrial-grade temperature tolerance, ultra-low power consumption, and NVSRAM technology, these systems ensure long-term stable timing performance while protecting metering data, and are designed to operate effectively in harsh environments such as outdoor and workshop settings.

In the portable device sector, products like GPS terminals, POS terminals, and portable blood glucose meters feature low power consumption to extend battery life, compact designs for slim profiles, and NV SRAM to ensure secure transaction and measurement data.

Medical electronics: Blood glucose meters and dosing dispensers — compatible with wide-voltage medical power systems, featuring data retention to ensure uninterrupted treatment processes and high reliability to meet the stringent requirements of medical equipment.

In the consumer and office equipment sector, devices such as set-top boxes, routers, and printers benefit from flexible packaging designs and square-wave output capabilities. These features support scheduled recording and task queuing, effectively reducing design costs.

In the telecommunications equipment sector, devices such as routers, switches, and servers feature automatic power switching functionality. The OSF flag ensures accurate network log timing, while high-speed I²C supports high-performance systems.