IPD2545A, IPD2547A, IPD2548A
2006-03-03
10
How to Load Information into the IPD25545/7/8A
Information loaded into the IPD2545/7/8A can be either ASCII data
or Control Word data. The following procedure (see also Typical
Loading Sequence) will demonstrate a typical loading sequence
and the resulting visual display. The word STOP is used in all of
the following examples.
Set Brightness
Step 1
Set the brightness level of the entire display to
your preference (example: 100%).
Load Four Characters
Step 2
Load a “S” in the left hand digit.
Step 3
Load a “T” in the next digit.
Step 4
Load an “O” in the next digit.
Step 5
Load a “P” in the right hand digit. If you loaded
the information correctly, the IPD2545A now
should show the word “STOP.”
Blink a Single Character
Step 6
Into the digit, second from the right, load the hex
code “CF,” which is the code for an “O” with the
D7 bit added as a control bit.
Note:
The “O” is the only digit which has the control bit
(D7) added to normal ASCII data.
Step 7
Load enable blinking character into the control
word register. The display now should show
“STOP” with a flashing “O”.
Add Another Blinking Character
Step 8
Into the left hand digit, load the hex code “D3”
which gives an “S” with the D7 bit added as a
control bit. The display should show “STOP” with
flashing “O” and a flashing “S.”
Alternate Character/Cursor Enable
Step 9
Load enable alternate character/cursor into the
control word register. The display now should
show “STOP” with the “O” and the “S” alternating
between the letter and cursor (all dots lit).
Initiate Four Character Blinking
(Regardless of Control Bit setting)
Step 10
Load enable display blinking. The display now
should show the entire word “STOP” blinking.
Electrical and Mechanical Considerations
The CMOS IC of the IPD2545/7/8A are designed to provide resis-
tance to both Electrostatic and Discharge Damage and Latch Up
due to voltage or current surges. Several precautions are strongly
recommended for the user, to avoid overstressing these built-in
safeguards.
ESD Protection
Users of the IPD2545/7/8A should be careful to handle the devices
consistent with standard ESD protection procedures. Operators
should wear appropriate wrist, ankle or feet ground straps and
avoid clothing that collects static charges. Work surfaces, tools
and transport carriers that come into contact with unshielded
devices or assemblies also should be appropriately grounded.
Latch up Protection
Latch up is condition that occurs in CMOS ICs after the input pro-
tection diodes have been broken down. These diodes can be
reversed through several means.
V
IN<GND, VIN>VCC +0.5 V, or through excessive currents begin
forced on the inputs. When these situations exist, the IC may
develop the response of an SCR and begin conducting as much as
one amp through the V
CC pin. This destructive condition will persist
(latched) until device failure or the device is turned off.
The Voltage Transient Suppression Techniques and buffer inter-
faces for longer cable runs help considerably to prevent latch con-
ditions from occurring. Additionally, the following Power Up and
Power Down sequence should be observed.
RoHS Compliance
The IPD2547A, IPD2545A, IPD2548A Intelligent Displays
TM are
hermetically sealed displays using a ceramic and glass construc-
tion. These components are not lead (Pb) free but are RoHS Com-
pliant based on the RoHS Compliance Directive's Annex,
paragraphs 5 and 7. These exemptions allow for lead (Pb) in glass
and ceramic electronic components. Refer to the following ex-
cerpts from the RoHS Compliance Directive Annex:
Applications of lead, mercury, cadmium and hexavalent chromium,
which are exempted from the requirements of Article 4(1)
5. Lead in glass of cathode ray tubes, electronic components and
fluorescent tubes.
7. Lead in electronic ceramic parts (e.g. piezoelectronic devices).
Typical Loading Sequence
CEO
CE1
RD
WR
A2
A1
A0
D7
D6
D5
D4
D3
D2
D1
D0
Display
1.
L
H
L
X
0
1
2.
L
H
L
H
0
1
0
1
0
1
S
3.
L
H
L
H
L
0
1
0
1
0
1
0
ST
4.
L
H
L
H
L
H
0
1
0
1
STO
5.
L
H
L
H
L
0
1
0
1
0
STOP
6.
L
H
L
H
L
H
1
0
1
STOP
7.
L
H
L
X
0
1
0
1
STO*P
8.
L
H
L
H
1
0
1
0
1
S*TO*P
9.
L
H
L
X
0
1
STOP
10.
L
H
L
X
0
1
0
1
S*T*O*P*
* Blinking character, Character alternating with cursor (all dots lit)