ICM7243 is an 8-character, alphanumeric display driver and controller that provides all the circuits needed to connect a microprocessor or digital system to a 14 - or 16-segment display. It is primarily used in microprocessor systems to minimize hardware and software overhead. On the chip, a 64-character ASClI decoder, 8x6 memory, high-power character and segment drivers, and multiplex scanning circuits are integrated.
Functional Block Diagram
The 6-bit ASCll data to be displayed is written directly to memory from the microprocessor data bus. Data location depends on the choice of sequence (MODE = 1) or random access MODE (mode = 0). In sequential access mode, the first entry is stored in the lowest position and displayed in the "leftmost" character position. Each subsequent entry is automatically stored in the next higher position and displayed "to the right" of the previous entry. Provide a DISPlay FULL signal after 8 inputs; The signal can be used for device cascades. A CLeaR pin is provided to clear memory and reset the location counter.
Test Circuit
Random access mode allows the processor to select a memory address and display number for each input word. Character multiplexing runs as long as no data is entered. It scans the memory and CHARacter drivers and ensures that the decoding from memory to display is done in the correct order. Provides intercharacter hiding to avoid showing ghosting
Performance curve
