Clocks

The NE555P are precision timing circuits capable of producing accurate time delays or oscillation. In the time-delay or monostable mode of operation, the timed interval is controlled by a single external resistor and capacitor network. In the a stable mode of operation, the frequency and duty cycle can be controlled independently with two external resistors and a single external capacitor. The threshold and trigger levels normally are two-thirds and one-third, respectively, of VCC. These levels can be altered by use of the control-voltage terminal.

Features
1. An RTC-DS1302 module that uses a DS1302 serial real-time clock (RTC) chip.
2. The RTC counts seconds, minutes, hours, date of the month, day of the week, month, and year leap-year compensation valid up to the year 2100.
3. It operates in either the 24-hour or 12-hour format (with an AM/PM indicator).
4. High performance, low power consumption; with 31 bytes of static RAM.
5. Working voltage: 2.5V ~ 5.5V; PCB size: 2.5 x 2.5 cm.