DSD-40BCD-GS ETC1 [List of Unclassifed Manufacturers], DSD-40BCD-GS Datasheet - Page 3

• Manufacturer Part Number: DSD-40BCD-GS
• Description: Miniature 4 1/2 Digit, BCD Input Slave LED Display
• Manufacturer: ETC1 [List of Unclassifed Manufacturers]

5. Controlling Display Brightness: The LED current-setting
6. Highlighting Selected Digits: In many instrument designs, it is
7. Power Supply Decoupling: The DSD-40BCD is not sensitive to
Notes:
1. Maximum allowable digit-to-digit overlap is 5 sec.
2. Maximum allowable digit-to-BCD data skew is also 5 sec.
never displayed, the POLARITY input may be left open.
components inside the DSD-40BCD are selected to produce
good display brightness — while keeping power dissipation at
reasonable levels — with a 20% duty cycle. Since no data latches
are utilized in the DSD-40BCD design, the user can exercise full
control over how many digits are enabled, and their relative
brightness, by manipulating the duty cycle of the DIGIT DRIVE
input.
respective DIGIT DRIVE input (DIGIT DRIVE 5 in this example)
open or low. If the timing relationships remain unchanged (i.e.,
20% duty cycle), the display brightness will remain the same as
when all five digits are used. However, if the duty cycle is changed
to 25% (because only four digits are used), the increase in display
intensity will be noticeable. In most applications, this increase in
intensity will not be significant enough to justify any timing
changes.
sometimes desirable to highlight or "flash" one particular digit to
draw the user's attention to that digit. Once again, duty cycle
control of the digit drive inputs makes this a relatively simple task.
The easiest way is to flash the digit on and off, at a 0.5 to 1Hz
rate, with the DIGIT DRIVE input. Keeping the duty cycle fixed at
20% for 5-digit applications, and 25% for 4-digits, will keep the
intensity of the non-flashed digits uniform.
logic noise or spikes, on either the 5V supply or the data inputs,
because it does not use any edge-triggered logic. However, it
does generate a fair amount of switching transients due to the
display's multiplexed architecture. A tantalum electrolytic
capacitor, in the range of 15 to 22µF, in parallel with a 0.1µF
ceramic capacitor will reduce the LED switching transients.
These two capacitors should be located as close as possible to
pins 1 and 3.
the high sink currents that DP1- DP4 do. If negative readings are
To turn off one digit, for a four digit application, simply leave the
DIGIT DRIVE 1
DIGIT DRIVE 3
DIGIT DRIVE 2
DIGIT DRIVE 4
DIGIT DRIVE 5
BCD DATA
(4 LINES)
(MSD)
(LSD)
4 ½ D I G I T , S L A V E L E D D I S P L A Y
Approx. 2msec
Approx. 2msec
Figure 2. BCD Data Timing Diagram
MSD
1
2
3
Approx. 8msec
3
10.
11.
8. Interfacing BCD-Output A/D Converters: The DSD-40BCD
9. DISPLAY TEST (Pin 2): The DSD-40BCD's display can have all
Panel mounted:
4
accepts the BCD data from DATEL's DMS-40PC-X-RS-BCD
Series, 4½ Digit Panel Meters. DMS-40PC meters are exactly the
same size as the DSD-40BCD display making it ideal for use in
remote-display applications.
4½ digit, integrating A/D converter's BCD and DIGIT DRIVE
outputs. The only difference is that the ICL7135 has its five DIGIT
DRIVE outputs labeled in a right-to-left order, i.e., the 7135's
MSD is labeled digit 5 and its LSD is labeled digit 1. This is
opposite to the DSD-40BCD labeling its MSD digit 1 and its
LSD digit 5. Please refer to the 7135's data sheet for more
information.
its segments enabled by bringing DISPLAY TEST low. The
display will show "–18888" (excluding the decimal points) as long
as the digit drive inputs are continuously strobed.
withstand most common manual and wave soldering operations.
However, we highly recommend that you evaluate the effects your
particular soldering techniques may have on the display's
polycarbonate case and overall performance. We also recom-
mend the use of no-clean solders since their residue normally
has no detrimental effects on low-speed digital devices.
connectors when panel mounting the DSD-40BCD. SAMTEC's
HCS series of IDC cable strips can be ordered in a variety of
lengths and connector terminations. Please contact SAMTEC,
Inc. at:
The DSD-40BCD will also interface directly with the ICL7135,
Soldering Methods: DSD-40BCD Series displays easily
Suggested Mating Connectors:
Board mounted:
DATEL recommends the use of IDC (insulation displacement)
LSD
5
Socket
USA (Indiana)
Europe (Scotland)
Asia (Singapore)
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DATEL P/N 39-2359624
812-944-6733
01236-739292
65-745-5955
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Fax: [phone]
Fax: [phone]
Fax: [phone]
DSD-40BCD