The part number " MCP7940N-I/SN " belongs to Microchip Technology, a leading manufacturer of microcontrollers, memory, and analog semiconductors.
MCP7940N-I/SN Overview:
The MCP7940N is a real-time Clock (RTC) with an integrated EEPROM and battery backup. It is designed to operate in low- Power applications where accurate timekeeping is essential, and is typically used in systems such as embedded applications, industrial control, and battery-powered devices.
Package Information and Pin Function:
The MCP7940N-I/SN is available in the following package:
SOIC-8 package (8-pin Small Outline Integrated Circuit).Pin Function Details:
Below is a detailed explanation of the MCP7940N-I/SN's 8-pin SOIC-8 package, including the function of each pin.
Pin Number Pin Name Pin Function 1 VSS Ground Pin. Connect to the ground of the system. 2 SCL I2C Serial Clock Input Pin. Used for the I2C clock signal. 3 SDA I2C Serial Data Input/Output Pin. Used for bidirectional data transfer. 4 INT Interrupt Output Pin. This pin generates an interrupt when specific events occur (e.g., alarm). 5 VDD Power Supply Pin. Connect to the power source, typically 2.5V to 5.5V. 6 NC No Connection. This pin is unused and not connected internally. 7 A2 Address Pin. Used to set the I2C address for the device. 8 A1 Address Pin. Used to set the I2C address for the device. Pin Descriptions: VSS (Pin 1): This pin is connected to the system ground. SCL (Pin 2): This is the serial clock pin for the I2C interface . It is used to clock the data in and out during I2C communication. SDA (Pin 3): The serial data pin is the data line for the I2C communication protocol. It is bidirectional, meaning data can flow both to and from the MCP7940N. INT (Pin 4): This pin outputs an interrupt signal when a set condition, such as an alarm or event, occurs. This pin can be used to notify the host system about specific time events. VDD (Pin 5): The VDD pin is the power supply pin. The MCP7940N works within a supply voltage range of 2.5V to 5.5V. NC (Pin 6): This is a No Connection pin, which means it is not internally connected to any circuitry within the device. It can be left unconnected in your design. A2 (Pin 7): This pin sets the I2C address bits for the MCP7940N. The address is selected by connecting this pin to either VSS or VDD. A1 (Pin 8): This pin also sets the I2C address bits, similarly to A2. The address is determined by the configuration of both A1 and A2.FAQ (Frequently Asked Questions) for MCP7940N-I/SN:
1. What is the MCP7940N-I/SN?The MCP7940N-I/SN is a real-time clock (RTC) IC with an integrated EEPROM. It uses the I2C protocol for communication and includes features such as an interrupt output and a battery backup.
2. What is the main function of the MCP7940N-I/SN?The primary function of the MCP7940N-I/SN is to provide accurate timekeeping in systems that require time-based operations, with a built-in EEPROM for storing data.
3. How does the MCP7940N-I/SN communicate with other devices?The MCP7940N-I/SN communicates via the I2C interface, using the SDA (Serial Data) and SCL (Serial Clock) pins.
4. What is the range of operating voltage for the MCP7940N-I/SN?The operating voltage range for the MCP7940N-I/SN is between 2.5V and 5.5V.
5. What are the key features of the MCP7940N-I/SN? Real-time clock functionality Integrated EEPROM for storing data Low power consumption I2C communication interface Interrupt output Battery backup functionality 6. How does the interrupt pin (INT) work?The INT pin generates an interrupt signal when a pre-configured event occurs, such as the expiration of an alarm or time threshold.
7. How is the I2C address set in the MCP7940N-I/SN?The I2C address is set using the A1 and A2 pins. By connecting these pins to either VSS or VDD, you can configure the address for I2C communication.
8. Can the MCP7940N-I/SN operate without a backup battery?No, the MCP7940N-I/SN requires a backup battery to maintain accurate timekeeping when the main power supply is off.
9. What is the maximum current consumption of the MCP7940N-I/SN?The MCP7940N-I/SN typically consumes a very low current of around 1µA during battery backup mode, making it suitable for battery-powered applications.
10. What happens if the I2C communication is interrupted?If the I2C communication is interrupted, the MCP7940N-I/SN will resume communication when the bus becomes available again, and any pending operations will continue as normal.
11. Can the MCP7940N-I/SN store data in its EEPROM?Yes, the MCP7940N-I/SN has an integrated EEPROM that can store data such as time configuration or user-specific information.
12. What is the purpose of the SDA and SCL pins?The SDA (Serial Data) and SCL (Serial Clock) pins are used for I2C communication. The SDA pin transmits data, while the SCL pin provides the clock signal for synchronizing communication.
13. What is the significance of the A1 and A2 pins?The A1 and A2 pins are used to set the I2C address for the MCP7940N-I/SN. By configuring these pins, you can select the unique address for the device on the I2C bus.
14. Can I use the MCP7940N-I/SN with other communication protocols?No, the MCP7940N-I/SN only supports I2C communication and cannot be used with other protocols such as SPI or UART.
15. What is the typical clock frequency for I2C communication?The typical I2C clock frequency for the MCP7940N-I/SN is 100 kHz (Standard Mode) or 400 kHz (Fast Mode).
16. Can the MCP7940N-I/SN be used in 5V systems?Yes, the MCP7940N-I/SN can operate in systems with a 5V power supply, as its operating voltage range includes 5V.
17. What is the package type of the MCP7940N-I/SN?The MCP7940N-I/SN comes in a SOIC-8 package, which has 8 pins in a small outline.
18. What is the purpose of the battery backup in the MCP7940N-I/SN?The battery backup allows the MCP7940N-I/SN to maintain accurate time even when the main power supply is disconnected or turned off.
19. How do I configure the alarm feature in the MCP7940N-I/SN?The alarm feature can be configured through the I2C interface. By setting specific values in the device's registers, you can define the time at which the alarm should trigger.
20. What is the accuracy of the MCP7940N-I/SN's real-time clock?The accuracy of the MCP7940N-I/SN’s RTC is typically within ±20ppm, depending on the operating conditions and temperature.
This information should provide a complete overview of the MCP7940N-I/SN, including its pin functions, packaging details, and answers to common user questions.