DM7856/DM8856. DM8857. DM7858/DM8858
BCD-to-7-segment LED drivers
This series of 7-segment display drivers fulfills a
wide variety of requirements for most active high
(common cathode) Light Emitting Diodes (LEDs).
Each device fully decodes a 4-bit BCD input into
a number from 0 through 9 in the standard 7-
segment display format, and BCD numbers above
9 into unique patterns that verify operation. All
circuits operate off of a single 5.0V supply.
The DM7856/DM8856 has active-high, passive
pull-up outputs which provide a typical source
current of 6.0 mA at an output voltage of 1.7V.
The applications are the same as for the DM5448/
DM7448 except that more design freedom is
allowed with higher source current levels. This
circuit was designed to drive the MAN-4 or equiv-
alent type display directly without the use of
external current limit resistors.
The DM8857 has active-high outputs and is de-
signed to be used with common cathode LED's
in the multiplex mode. It provides a typical source
current of 50 mA at an output voltage of 2.3V.
In addition, with the use of an external current
limit resistor per segment, this circuit can be used
in higher current nonmultiplex LED applications.
The DM7858/DM8858 has active high outputs
with source current adjustable with the use of
external current limit resistors, one per segment.
This feature allows extreme flexibility in source
current value selection for either multiplex or
non-multiplex common cathode LED drive applica-
tions. It allows the system designer freedom to tailor
the drive current for his particular applications.
• Lamp-test input
• Leading/trailing zero suppression (RBI and
• Blanking Input that may be used to modulate
lamp intensity or inhibit output
• TTL and DTL compatible
• Input clamping diodes
Dual-In-Line and Flat Package
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~ TEST OUTPUT IIIIPUT
Order Number DM7856J, DM8856J,
DM8857J, DM7858J, DM8858J
See Package 17
Order Numbar DM7856N, DM8856N,
DM7858N or DM8858N
Sea Package 23
Ordar Number DM7856W, DM8856W,
See Package 28
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IIUMERICAL DESIGNATIONS - RESULTANT DIIPlAYS