HT 1380

The HT1380 is a serial timekeeper IC which provides seconds, minutes, hours, day, date, month and year information. The number of days in each month and leap years are automatically adjusted. The HT1380/HT1381 is designed for low power consumption and can operate in two modes: one is the 12-hour mode with an AM/PM indicator, the other is the 24-hour mode.The HT1380/HT1381 has several registers to store the corresponding information with 8-bit data format. A 32768Hz crystal is required to provide the correct timing. In order to minimize the pin number, the HT1380/HT1381 use a serial I/O transmission method to interface with a microprocessor. Only three wires are required: (1) REST, (2) SCLK and (3) I/O. Data can be delivered 1 byte at a time or in a burst of up to 8 bytes.

HT 1380 Features 

• Operating voltage: 2.0V~5.5V 
• Maximum input serial clock: 500kHz at VDD=2V, 2MHz at VDD=5V
• Operating current: less than 400nA at 2V, less than 1.2A at 5V 
• TTL compatible VIH: 2.0V~VDD+0.3V at VDD=5V VIL: 0.3V~+0.8V at VDD=5V
• Two data transmission modes: single-byte, or burst mode 
• Serial I/O transmission 
• All registers store BCD format 
• HT1380: 8-pin DIP package HT1381: 8-pin SOP package

Developer: HT1380_Datasheet