
MC14489
MOTOROLA
1
CMOS
The MC14489 is a flexible light–emitting–diode driver which directly
interfaces to individual lamps, 7–segment displays, or various combinations of
both. LEDs wired with common cathodes are driven in a multiplexed–by–5
fashion. Communication with an MCU/MPU is established through a synchro-
nous serial port. The MC14489 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 any one of the following: a 5–digit display plus
decimals, a 4–1/2–digit 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 on–chip decoder outputs 7–segment–format numerals 0 to 9,
hexadecimal characters A to F, plus 15 letters and symbols.
The MC14489 is compatible with the Motorola SPI and National MICRO-
WIRE
serial data ports. The chip’s patented BitGrabber
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 6 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 via
Serial Port
Special Circuitry Minimizes EMI when Display is Driven and Eliminates
EMI in Low–Power Mode
Power–On Reset (POR) Blanks the Display on Power–Up, Independent of
Supply Ramp Up Time
May Be Used with Double–Heterojunction LEDs for Optimum Efficiency
Chip Complexity: 4300 Elements (FETs, Resistors, Capacitors, etc.)
See Application Note AN431,
Temperature Measurement and Display
Using the MC68HC05B4 and the MC14489
and Engineering Bulletin
EB153,
Driving a Seven–Segment Display with the N
EURON
C
HIP
BitGrabber is a trademark of Motorola Inc.
MICROWIRE is a trademark of National Semiconductor Corp.
Order this document
by MC14489/D
SEMICONDUCTOR TECHNICAL DATA
PIN ASSIGNMENT
P SUFFIX
PLASTIC DIP
CASE 738
DW SUFFIX
SOG PACKAGE
CASE 751D
ORDERING INFORMATION
MC14489P
MC14489DW
Plastic DIP
SOG Package
b
d
VDD
e
f
ENABLE
BANK 1
Rx
a
c
5
4
3
2
1
10
9
8
7
6
14
15
16
17
18
19
20
11
12
13
BANK 4
BANK 5
DATA OUT
h
g
CLOCK
DATA IN
BANK 2
VSS
BANK 3
20
1
20
1
REV 3
10/95