General Description
The HT1330 is a CMOS fabricated LSI chip designed to drive a standard three and 1/2 digit biplexed LCD for a count-up/down timer in watch applications. The watch and timer are based on a 32768Hz quartz crystal oscillator. The maximum count-down time is 20 hours with an accuracy of 1 second. The maximum count-up period is 20 hours, but the LCD will normally display a maximum period of 19 minutes and 59 seconds. If the user presses switch "S2", the total count-up time in hours and minutes will be displayed. In the count-up/down mode, the real time can be seen by pressing switch "S1" and return to the count-up/down mode by releasing "S1".

Features
• A real time watch
• A 20-hour adjustable range setting count-down timer
• 20-minute count-up display cycle time
• 20 hours of count-up time maximum
• Auto recycle or manual reset the count-down timer by bonding option
• Hours and minutes are set independently
• Real time display in timer mode
• 5-minute/10-minute pre-alarm
• DC output and piezo output
• An internal voltage doubler
• Busy flag output high in timer counting
• 3 1/2 digit LCD display
• 32768Hz crystal oscillator
• Single 1.5V battery operation
• 48L-pin QFP package