Clock/Timing - Real Time Clocks are a family of integrated circuits that can keep track of the current time and date. MCP7940NT-I/SN is a Real Time Clock (RTC) IC designed specifically to track time accurately and provide precise timing. This device is used in a wide range of applications that demand precise time keeping including calendar clock controllers, consumer applications and time-stamping systems.

MCP7940NT-I/SN Application Field

MCP7940NT-I/SN is a single-chip, low-power, real-time clock (RTC) IC designed to provide accurate time/date keeping and interpolation capabilities as well as precision time-stamping for consumer applications and a wide variety of other applications.

MCP7940NT-I/SN provides high-precision, low-power timekeeping with a single-chip solution. This device includes an integrated oscillator, crystal control and resistors, so no additional external components are required. It provides an ultra-low power timekeeping solution while delivering precision time and date generation. MCP7940NT-I/SN is designed specifically to support the development of systems, including hand-held devices, appliances and personal computers, that require minute-by-minute time keeping accuracy, even during sleep or power down mode.

MCP7940NT-I/SN is used in a variety of applications such as industrial and domestic timer, calendar clock controllers, time-stamping systems, faxback, data logging and battery-backed/EPROM storage.

MCP7940NT-I/SN Working Principle

MCP7940NT-I/SN is based on a crystal oscillator circuit, with a quartz crystal, two free running oscillators and a peripheral counter chain to keep track of the time and date. It also incorporates an intelligent oscillator control circuit, enabling accurate timekeeping and improved power efficiency.

The MCP7940NT-I/SN oscillator circuit is designed to operate at a range of oscillator frequencies, with a accuracy of ±2%. The oscillator terminal is connected with a high-accuracy external crystal, and the oscillator frequency is selectable using the XTAL bits in the device’s registers.

The crystal oscillator is connected with the real time counters in the device, which is used to count the days, hours, minutes and seconds. It also includes two 32-bit registers that are used to store the current time/date and an alarm time/date. The device is programmed to trigger an interrupt when an alarm time/date is matched. This alarm feature can be used to generate periodic events.

MCP7940NT-I/SN also includes a power-on-reset circuit, which is used to reset the device\'s internal counters when the power level drops below a certain predefined threshold. This ensures that the device is synchronized with the real time even if it was powered down for a certain period.

MCP7940NT-I/SN also includes an integrated non-volatile memory that is used to store the current time/date information and other configuration bits when the power is switched off. This enables the device to keep track of the time even when powered off.

In addition, MCP7940NT-I/SN also provides an integrated temperature detector, which can be used to measure the temperature of the surrounding environment. This enables the device to provide a more accurate timekeeping by compensating any variations in the oscillator frequency due to temperature changes.

Conclusion

MCP7940NT-I/SN is an ultra low power, single chip RTC IC designed for precision time keeping applications. It features an integrated oscillator, crystal control, a 32-bit register for time/date storage, an alarm function, power-on-reset and an integrated temperature sensor. This device is used in a wide range of applications that demand precise time keeping, including calendar clock controllers, consumer applications and time-stamping systems.