The MC14489 is a flexible lightemittingdiode driver which directly interfaces to individual lamps, 7segment displays, or various combinations of both. LEDs wired with common cathodes are driven in a multiplexedby5 fashion. Communication with an MCU/MPU is established through a synchronous serial port. The MC14489 features data retention plus decode and scan circuitry, thus relieving processor overhead. A single, currentsetting resistor is the only ancillary component required. A single device can drive any one of the following: a 5digit display plus decimals, a 41/2digit display plus decimals and sign, or 25 lamps. A special technique allows driving 5 1/2 digits; see Figure 16. A configuration register allows the drive capability to be partitioned off to suit many additional applications. The onchip decoder outputs 7segmentformat numerals 0 to 9, hexadecimal characters A to F, plus 15 letters and symbols. The MC14489 is compatible with the Motorola SPI and National MICROWIRETM serial data ports. The chip's patented BitGrabberTM registers augment the serial interface by allowing random access without steering or address bits. A 24bit transfer updates the display register. Changing the configuration register requires an 8bit transfer.