UM3032A

The UM3032A has the following features including 8-Digit number capacity with floating decimal point;Memory (M), negative(-)and error (E) symbols;Memory calculations;Leading zero and trailing zero suppression;Multiplexed output for direct diving of LCD;On-Chip  clock  generator  that  requires  no  external circuits;On-Chip keyboard encoding and debouncing circuit;Power-On/clear and power-off keys;Automatic  power-off, typically  6 minutes after the last key entry.

The UM3032A is an 8-digit,one-memory IC. It provides an on-chip  clock  generator,input pins for keyboard matrix,and all necessary pins for direct driving of a liquid crystal display. The UM3032A is intended for battery-operated, hand-held calculators.Stresses above those  listed under "Absolute Maximum Ratings"  may  cause  permanent damage to the device.These are stress ratings only. Functional operation of this device at these or any other conditions above those indicated in the operational sections of this specification is not implied and exposure to absolute maximum rating conditions for extended periods may affect device reliability.

The purpose of the percent key is to allow for calculation of addon and discount. Determination of add-0n requires the principal amount to be the first entry followed by the"+"or "x" key, with the percentage being the second entry. Depression of the percent key yields the amount to add on, such as tax or interest. Depression of the,key adds this amount to be principal.The first number key in a sequence will clear the display and enter the digit in the display. Successive entries will shift the display left and enter data in the display register.The first decimal point entered is effective. An attempted entry of more than 8 digits or 7 decimal places will be ignored.The constant calculation is performed automatically by the=key,%key, or%=keys without a constant switch. The second operand is treated as the constant for addition, substraction, and division, while the first operand is the constant for multiplication.If any number except zero is in the memory, the symbol digit will display an "M".If no key is depressed for 6 minutes, an internal automatic power-off. circuit will turn off the power.