mm5484 National Semiconductor Corporation, mm5484 Datasheet - Page 3

• Manufacturer Part Number: mm5484
• Description: Mm5484 16-segment Led Display Driver
• Manufacturer: National Semiconductor Corporation

Functional Description
The MM5484 is designed to drive LED displays directly Se-
rial data transfer from the data source to the display driver is
accomplished with 3 signals DATA IN CLOCK and EN-
ABLE The signal ENABLE acts as an envelope and only
while this signal is at a logic ‘1’ do the circuits recognize the
clock signal
While ENABLE is high data on the serial data input is trans-
ferred and shifted in the internal shift register on the rising
clock edge i e a logic ‘0’ to logic ‘1’ transition
Timing Diagram
Physical Dimensions
inches (millimeters)
Molded Dual-In-Line Package (N)
NS Package Number N22A
Order Number MM5484N
FIGURE 3
3
When the ENABLE signal goes to a low (logic zero state)
the contents of the shift register is latched and the display
will show the new data While new data is being loaded into
the SR the display will continue to show the old data
For the MM5484 data is output from the serial DATA OUT
pin on the falling edge of clock so cascading is made simple
with race hazards eliminated
When the chip first powers on an internal power on reset
signal is generated which resets the SR and latches to zero
so that the display will be off
TL F 6141 – 5