The DS17287-5+ is a real time clock in 24 pin EDIP package. It provides a real time clock/calendar, one time of day alarm, three maskable interrupts with a common interrupt output, a programmable square wave and 114bytes of battery-backed NV SRAM. It integrates a quartz crystal and lithium energy source. The power control circuitry allows the system to be powered on by an external stimulus such as a keyboard or by a time and date (wake-up) alarm. The active-low power-on reset output pin is triggered by one or either of these events and is used to turn on an external power supply. This pin is under software control so that when a task is complete, the system power can shut down. The date at the end of the month is automatically adjusted for months with fewer than 31 days including correction for leap years. A precision temperature-compensated circuit monitors the status of VCC. If a primary power failure is detected, the device automatically switches to a backup supply.
- Supply voltage range is 4.5V to 5.5V
- Operating temperature range from 0°C to 70°C
- RTC counts seconds, minutes, hours, day, date, month & year with leap year compensation through 2099
- SMI recovery stack
- Crystal select bit allows operation with 6pF or 12.5pF crystal
- 12hour or 24hour clock with AM and PM in 12hour mode
- UL recognized
- RAM clear function
- Interrupt output with six independently maskable interrupt flags
- Programmable square wave output
时钟与计时
(EN)
