UPD4991AGS-A

Real Time Clock Overview

The µPD4991AGS-A is a CMOS integrated circuit functioning as a Real Time Clock (RTC) with volatile memory and one timer. It facilitates the input and output of 4-bit parallel time data and calendar data to and from a microcomputer. The device is housed in a PDSO package, designed for integration into digital systems requiring precise timekeeping capabilities.

Real Time Clock Feature Summary

• Provides 4-bit parallel interface for time and calendar data exchange with microcomputers
• Integrates a single timer function within the RTC architecture
• Utilizes CMOS technology for efficient power consumption

Real Time Clock Applications

• Industrial control systems requiring time-stamping
• Consumer electronics with clock functionality
• Digital systems needing calendar data synchronization

Real Time Clock Procurement Notes

Verify the specific ordering suffix and package variant against official Renesas documentation to ensure compatibility. Confirm that the volatile nature of the RTC memory aligns with system power management strategies, as external backup may be required for continuous operation during power loss.

Real Time Clock Selection Notes

Select this component when a dedicated RTC with parallel 4-bit interface is required for microcomputer integration. Consider the volatile memory characteristic and ensure the application supports appropriate power backup mechanisms to maintain time data integrity across power cycles.

Real Time Clock Part Context

This part belongs to the µPD4991A series of real-time clock ICs manufactured by Renesas Electronics Corporation. It represents a specialized solution for embedded applications where direct parallel communication with a host microprocessor is preferred over serial protocols for time data retrieval.

Real Time Clock FAQ

Is the memory in the UPD4991AGS-A non-volatile?

No, the RTC memory is volatile. Data retention depends on continuous power supply or an external backup source.

What type of interface does the UPD4991AGS-A use for data transfer?

It uses a 4-bit parallel interface for inputting and outputting time and calendar data to/from a microcomputer.