DS1746W-120

The DS1746W-120 is a non-volatile memory chip manufactured by Maxim Integrated Products for use in real time clocks or event and timer applications. The DS1746W-120 is a 2-Wire Serial (I2C) device which comes in a 14-pin DIP. It uses a battery to keep track of the time while the main power is off, and has a trickle charge feature to keep the battery charged while the device is powered on. The DS1746W-120 features a programmable clock/calendar chip with a 32kHz time source and a watchdog timer, which can be used to trigger an event if a certain condition is not met within a specified time period. Additionally, it features 8 user-programmable time-of-day alarm registers, 24 user-programmable single-byte registers, and 4 user-programmable “whole word” registers.

The DS1746W-120 can be used in a variety of applications, from real time clock, event, and timer applications to clock synchronization, automotive timing, remote monitoring, and access control. For example, it can be used for tracking the time of day, enable/disable functions and applications, alerting and security, timer/counter applications, and remote fault monitoring. It can also be used in embedded systems, to implement remote time synchronization and management, as well as providing a real-time clock/calendar information to the host processor.

In terms of its working principle, the DS1746W-120 functions by reading and writing data to and from its memory registers. The device can store up to 32 bytes of data in its non-volatile memory. When the main power is off, the RTC is powered by an on-chip battery for status retention, so that the clock and data registers continue to be updated. The device also includes an internal power-on reset circuit, which will automatically reset all registers and counters to their default state when power is applied.

The device also includes a watchdog timer, which must be periodically “kicked” in order to prevent the device from triggering a reset. The watchdog timer can be used to trigger an event if a certain condition is not met within a specified time period, such as if the main power fails or is disconnected. Additionally, the device features 8 user-programmable time-of-day alarm registers which can be used to set alarms to wake the system up at a specific time.

In conclusion, the DS1746W-120 is a highly versatile real time clock chip which can be used in a variety of applications. Its non-volatile 32kB memory stores data even when the main power is off, and its 8 user-programmable alarms make it ideal for task scheduling and remote timing applications. Furthermore, the included watchdog timer ensures that the system is running properly and that any unexpected events are handled appropriately.