LED DRVR 40Segment 5V 20-Pin SOIC W T/R

The MC14489B is a flexible light-emitting-diode driver which directly interfaces to individual lamps, 7-segment displays, or various combinations of both. LEOs wired with common cathodes are driven in a multiplexed-by-5 fashion. Communication with an MCUIMPU is established through a synchronous serial port. The MC 14489B features data retention plus decode and scan circuitry, thus relieving processor overhead. A single, current -setting resistor is the only ancillary component required. A single device can drive anyone of the following: a 5-digit display plus decimals, a 4-112-digit display plus decimals and sign, or 25 lamps. A special technique allows driving 5 112 digits. A configuration register allows the drive capability to be partitioned off to suit many additional applications. The on-chip decoder outputs 7-segment-format numerals O to 9, hexadecimal characters A to F, plus 15 1etters and symbols. The MC14489B is compatible with the Freescale SPI and National MI-CRO-WIRETM serial data ports. The chip"s patented BitGrabberTM registers augment the serial interface by allowing random access without steering or address bits. A 24-bit transfer updates the display register. Changing the configuration register requires an 8-bit transfer.

Operating Voltage Range of Drive Circuitry: 4.5 to 5.5 V

Operating Junction Temperature Range: -40° to 130°C

Current Sources Controlled by Single Resistor Provide Anode Drive

Low-Resistance FET Switches Provide Direct Common Cathode Interface

Low-Power Mode (Extinguishes the LEDs) and Brightness Controlled viaSerial Port

Special Circuitry Minimizes EMI when Display is Driven and Eliminates EMIin Low-Power Mode

Power-On Reset (POR) Blanks the Display on Power-Up, Independent ofSupply Ramp Up Time

May Be Used with Double-Heterojunction LEDs for Optimum Efficiency

Chip Complexity: 4300 Elements (FETs, Resistors, Capacitors, etc.)