2
7
The DDM 4 is a low power 4 digit data display module which usually operates under microprocessor control.
Inputs are CMOS and TTL compatible. Using three inputs; Clock, Data In and Load, it is possible to individually
address each LCD segment, permitting 0 to 9 and A to F to be displayed plus any other combination of the
segments. Hand-held cases for the DDM 4 are available (Veronex hand-held size 3 and OKW Type M and P
enclosures).
• 12.7mm (0.5“) Digit Height
• Easily Interfaced To Microprocessors
• Requires Only Three Control Lines
• 5V LED Backlighting
• Can be Cascaded
• Low Power
• CMOS and TTL Compatible
TIMING DIAGRAM
DC CHARACTERISTICS
PIN FUNCTIONS
AC CHARACTERISTICS
(15) -VE
5 Volt LED backlighting supply terminals.
(16) +VE
(2) VPOS
Positive supply voltage (VDD).
(1) VNEG
Negative supply voltage (VSS).
(3) LOAD
Load input: Causes a parallel load of the data from the shift register to the display latches at logic '1'.
(4) CK
Clock input: The shift register loads, shifts and outputs (DO) on the falling edge.
(5) DI
Data input: A logic '1' on DI causes a segment to be visible.
(6) DO
Data output: To be used for cascading modules.
For cascading: Connect DO to DI of next module. Each module will produce its own display drive. If an external driving signal is
used, connect it to each module's L0 input.
Do not connect backplane outputs together.
(7) L0
LCD driving signal input. Leave open circuit or use for synchronising cascaded modules (see Application diagram *).
(8) BP
Backplane output.
(9) DEGREES
(10) COLON
Inputs for degree, colon and pointer. Note: If not used, tie these inputs to BP.
(11) POINT
Note:
( ) Optional Plug 1 Pin Numbers
D
I
F
GB
t
pw
t
pd
t
ds
t
dh
CK
DI
LOAD
DO
31
32
31
32
1/f
Specification
Symbol Min.
Typ.
Max.
Unit
Supply voltage
V
+3.0
5
+8.5
V
Supply current
I
40
60
A
Operating temperature range
0
50
°C
Input High level
V
0.5V
V
V
Input Low level
V
0
0.1 V
V
Input leakage current
I
0.01
±10
A
Input capacitance
C
5.0
pF
Backlight voltage
V
5
5.5
V
Backlight current
I
50
75
mA
DD
DD
IH
DD
DD
IL
DD
L
I
LMP
LMP
µ
µ
Characteristics
Symbol Min.
Max.
Units
Conditions
Clock rate
f
0
1.5
MHz
50% duty cycle
Data set-up time
t
150
nS
Data change to
CK falling edge
Data hold time
t
50
nS
Load pulse width
t
175
nS
CL=55pF
Data out prop. delay
t
500
nS
ds
dh
pw
pd
DISPLAY SHIFT REGISTER ASSIGNMENT
Note: A segment is visible when a logic '1' is present. For correct operation of the display, 32 bits of data must be clocked in. When
clocking in 32 bits of display data the first input bit is the DP of digit 1 and the last bit is the G segment of digit 4.
AFFECTATION DU REGISTRE A DECALAGE DE L’AFFICHEUR
ZUORDNUNG DES ANZEIGEN-VERSATZREGISTERS
ASSEGNAZIONE DEL REGISTRO A SCORRIMENTO DEL DISPLAY
Note:
Anmerkung:
Nota:
Un segment est visible lorsqu’un ‘1’ logique est présent. Pour une utilisation correcte, 32 bits de données doivent être entrées.
Lorsque 32 bits de données sont transférés le premier bit de donnée est le point décimal du premier caractère et le dernier bit est
le segment G du quatrième caractère.
Ein Segment wird sichtbar, wenn eine logische ‚1' ansteht. Für einen korrekten Betrieb der Anzeige müssen 32 Datenbits
eingetaktet werden. Wenn 32 Anzeigedaten eingetaktet werden, dann ist das erste Eingangsbit der DP der Zahl 1 und das
letzte Bit das G-Segment der Zahl 4.
Un segmento è visibile quando è presente una logica "1". Per garantire il corretto funzionamento del display, devono essere
inseriti 32 bit di dati. Durante l'inserimento di 32 bit di dati, il primo bit introdotto è il DP della digit 1 e l'ultimo bit è il
segmento G della digit 4.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
G
F
A
B
C
D
E
DP
G
F
A
B
C
D
E
DP
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
G
F
A
B
C
D
E
DP
G
F
A
B
C
D
E
DP
DIGIT
CLOCK PULSE
SEGMENT
DIGIT
CLOCK PULSE
SEGMENT
CARACTÈRE
ZAHL
DIGIT
COUP D’HORLOGE
TAKTIMPULS
IMPULSO DI CLOCK
SEGMENT
SEGMENT
SEGMENTO
CARACTÈRE
ZAHL
DIGIT
COUP D’HORLOGE
TAKTIMPULS
IMPULSO DI CLOCK
SEGMENT
SEGMENT
SEGMENTO
Caractère
Caractère
ZAHL 4 'MSD'
(linke Zahl)
(digit sinistro)
Caractère 3
ZAHL 3
Caractère 2
ZAHL 2
Caractère
Caractère
ZAHL 1'LSD'
(rechte Zahl)
(digit destro)
DIGIT 4 'MSD'
(LH digit)
4 'MSD'
(LH
)
DIGIT 4 'MSD'
DIGIT 3
DIGIT 3
DIGIT 2
DIGIT 2
DIGIT 1 'LSD'
(RH digit)
1 'LSD'
(RH
)
DIGIT 1 'LSD'
A
G
D
F
E
DP
B
C
