5
Electrical/Optical Characteristics
T
A
= –55°C to +100°C
Description Symbol Test Conditions Min. Typ.
[7]
Max. Unit
Supply HDSP-078x Series I
CC
V
CC
= 5.5 V 78 105 mA
Current
HDSP-079x/-088x/-098x Series
Characters “5.” or
120 175
“B” displayed
Power HDSP-078x Series P
T
V
CC
= 5.5 V 390 573 mW
Dissipation
HDSP-079x/-088x/-098x Series
Characters “5.” or
690 963
“B” displayed
Logic, Enable and Blanking Low-Level V
IL
V
CC
= 4.5 V 0.8 V
Input Voltage
Logic, Enable High-Level Input Voltage V
IH
2.0 V
Blanking High-Voltage; Display Blanked V
BH
2.3 V
Logic and Enable Low-Level Input Current I
IL
V
CC
= 5.5 V –1.6 mA
Blanking Low-Level Input Current I
BL
V
IL
= 0.4 V –10 µA
Logic, Enable and Blanking High-Level I
IH
V
CC
= 5.5 V +40 µA
Input Current V
IH
= 2.4 V
Weight 1.0 gm
Leak Rate 5 x 10
-8
cc/sec
Notes:
4. The luminous intensity at a specific operating ambient temperature,
I
v
(T
A
), may be approximated from the following exponential equation:
I
v
(T
A
) = I
v
(25°C) e
[k(TA-25°C)]
.
Device K
HDSP-078 Series –0.0131/°C
HDSP-079x Series
HDSP-088x Series –0.0112/°C
HDSP-098x Series –0.0104/°C
5. The dominant wavelength, l
d
, is derived from the CIE chromaticity dia-
gram and represents the single wavelength which defines the color of
the device.
6. The HDSP-088X and HDSP-098X series devices are categorized as to
dominant wavelength with the category designated by a number on the
back of the display package.
7. All typical values at V
CC
= 5.0 V and T
A
= 25°C.
Operational Considerations
Electrical
These devices use a modied 4 x 7 dot matrix of light
emitting diodes to display decimal/hexadecimal numeric
information. The high eciency red and yellow displays
use GaAsP/GaP LEDs and the high performance green
displays use GaP/GaP LEDs. The LEDs are driven by con-
stant current drivers, BCD information is accepted by
the display memory when the enable line is at logic low
and the data is latched when the enable is at logic high.
Using the enable pulse width and data setup and hold
times listed in the Recommended Operating Conditions
allows data to be clocked into an array of displays at a
6.7 MHz rate.
The decimal point input is active low true and this data
is latched into the display memory in the same fashion
as the BCD data. The decimal point LED is driven by the
on-board IC.
The blanking control input on the hexadecimal displays
blanks (turns o) the displayed information without dis-
turbing the contents of display memory. The display is
blanked at a minimum threshold level of 2.0 volts. When
blanked, the display standby power is nominally 250 mW
at T
A
= 25°C.
The ESD susceptibility of the IC devices is Class A of MIL-
STD-883 or Class 2 of DOD-STD-1686 and DOD-HDBK-
263.
