MM54HC4543/MM74HC4543
BCD-to-7 Segment Latch/Decoder/Driver
for Liquid Crystal Displays
General Description
The MM54HC4543/MM74HC4543 BCD-to-7 segment
latch/decoder/driver utilize advanced silicon-gate CMOS
technology, and can be used either as a high speed decoder
or as a display driver. This circuit contains a 4-bit latch,
BCD-to-7 segment decoder, and 7 output drivers. Data on
the input pins flow through to the output when the LATCH
ENABLE (LE) is high and is latched on the high to low transition
of the LE input. The PHASE input (PH) controls the
polarity of the 7 segment outputs. When PH is low the outputs
are true 7 segment, and when PH is high the outputs
are inverted 7 segment. When the PHASE input is driven by
a liquid crystal display (LCD) backplane waveform the segment
pins output the correct segment waveform for proper
LCD AC drive voltages.
In addition a BLANKING INPUT (Bl) is provided, which will
blank the display.
The MM54HC4543/MM74HC4543 are functionally and pinout
equivalent to the CD4543BC/CD4543BM and the
MC14543BA/MC14543BC. All inputs are protected from
damage due to static discharge by diodes to VCC and
ground.