The CDP68HC68T1EZ is a CMOS Serial Real-Time Clock IC with RAM and power sense/control. It provides a time/calendar function, a 32 byte static RAM and a 3 wire Serial Peripheral Interface (SPI Bus). The primary function of the clock is to divide down a frequency input that can be supplied by the on-board oscillator in conjunction with an external crystal or by an external clock source. The internal oscillator can operate with a 32kHz, 1MHz, 2MHz or 4MHz crystal. An external clock source with a 32kHz, 1MHz, 2MHz, 4MHz, 50Hz or 60Hz frequency can be used to drive the CDP68HC68T1. The time registers hold seconds, minutes and hours, while the calendar registers hold day-of-week, date, month and year information. The data is stored in BCD format. In addition, 12 or 24 hour operation can be selected. In 12 hour mode, an AM/PM indicator is provided. The T1 has a programmable output which can provide one of seven outputs for use elsewhere in the system.
● SPI (Serial Peripheral Interface)
● Seconds, minutes, hour (12/24, AM/PM), day of week, date, month, year (0 to 99), automatic leap year
● 32 words x 8-bit RAM
● Seconds, minutes, hours alarm
● Automatic power loss detection
● 2.2V Low minimum standby (timekeeping) voltage
● Selectable crystal or 50/60Hz line input
● Buffered clock output
● Battery input pin that powers oscillator and also connects to VDD pin when power fails
● Three independent interrupt modes - Alarm, periodic, power-down sense
●ESD sensitive device, take proper precaution while handling the device.