IK2108A

TECHNICAL DATA
LED Driver IC
IK2108A
Description
The IK2108A are anode-grid LED display drives 5.0V~18.0V with output size – 8 digits x
14 segments to 12 digits x 10 segments and addition key scan function.
Serial interface provides connection with microprocessor.
Features
• Operation voltage for digital part: 3.0V ~ 5.5V
• Operation voltage for output LEDs: 5.0V ~ 18.0V
• 7-step individual dimming control for each grid
• OSC: built in (with external resistor) 500kHz @ R=12.1kΩ
• Pulse segment current: 27mA @ 8 digits x 14 segments
39mA @ 12 digits x 10 segments
• Key scanning: 10x3 matrix
• Serial Interface
• Operation Temperature : -40 ~ 85°C
SOP-32
LQFP-32
Application
• Washing machine,refregerator, microwave oven, conditioner and other
ORDERING INFORMATION
Device
IK2108ADW
IK2108ADWT
IK2108ALQ
Operating
Temperature Range
Package
Shipping
TA = -40 to 85 C
SOP 32
SOP 32
LQFP-32
Tube
Tape&Reel
Tape&Reel
Pin Description IK2108A (32Pins)
RCUR
1
32
GR1
DI/O
2
31
GR2
CLK
3
30
GR3
STB
4
29
GR4
K1
5
28
GR5
K2
6
27
GR6
K3
7
26
GR7
VDD
8
25
GR8
GND
9
24
VCC
SG1/KS1
10
23
SG14/GR9
SG2/KS2
11
22
SG13/GR10
SG3/KS3
12
21
SG12/GR11
SG4/KS4
13
20
SG11/GR12
SG5/KS5
14
19
SG10/KS10
SG6/KS6
15
18
SG9/KS9
SG7/KS7
16
17
SG8/KS8
IK2108A
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May 2012, Ver. 03
IK2108A
Pin №
Pin Name
I/O
Description
SOP-32
LQFP32
I/O
A resistor is connected to this pin to determine the output
currents and oscillation frequency.
1
30
DI/O
I/O
Data Input - Output Pin
This pin inputs serial data at the rising edge of the shift clock
(starting from the bit)
Data Output Pin - N-Channel, Open-Drain
This pin outputs serial data at the falling edge of the shift clock
2
31
CLK
I
3
32
STB
I
4
1
K1 to K3
I
Key Data Input Pins
The data sent to these pins are latched at the end of the display
cycle. (Internal Pull-Up Resistor)
5-7
2-4
VDD
VCC
SG1/KS1 to
SG10/KS10
SG11/GR12 to
SG14/GR9
GR8 to GR1
GND
-
Power Supply for Digital Part
8
5
Power Supply for Output Part
RCUR
Clock Input Pin
This pin reads serial data at the rising edge and output data at
the falling edge.
Serial Interface Strobe Pin
The data input after the STB has fallen is processed as a
command.
When this pin is HIGH, CLK is ignored.
24
21
O
Segment Output Pins (N-channel open drain)
Also acts as the Key Source
10-19
7-16
O
Segment / Grid Output Pins
20-23
17-20
O
-
Grid Output Pins (P-Channel, Open Drain)
25-32
22-29
9
6
Ground Pin
BLOCK DIAGRAM
Control
DI/O
CLK
STB
RCUR
Serial
Data
Interface
Display
Memory
OSC
Timing
Generator
Current
Reference
Key Matrix
Memory
Segment
Driver/
Key Scan
Output/
Grid
Driver
Dimming
Circuit
R
GND
Voltage
Reference
K1 K2 K3
SG1/KS1
SG2/KS2
SG3/KS3
SG4/KS4
SG5/KS5
SG6/KS6
SG7/KS7
SG8/KS8
SG9/KS9
SG10/KS10
SG11/GR12
SG12/GR11
SG13/GR10
SG14/GR9
GR8
GR7
GR6
GR5
GR4
GR3
GR2
GR1
VDD VCC GND
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May 2012, Ver. 03
IK2108A
INPUT / OUTPUT CONFIGURATIONS
The schematic diagrams of the input and output circuits of the logic section are shown below.
Input Pins: CLK, STB
VDD
GND
Input Pins: K1, K2, K3
Output Pins: GR1 to GR8
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IK2108A
Output Pins: SG1/KS1 to SG10/KS10
GND
Output Pins: SG11/GR12 to SG14/GR9
Input-Output Pin: DI/O
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May 2012, Ver. 03
IK2108A
FUNCTIONAL DESCRIPTION
Commands
A command is the first byte (b0 to b7) inputted to IK2108A via DI/O Pin after STB Pin has changed
from ”HIGH” to “LOW” state. If for some reason the STB Pin is set “HIGH” while data or commands
are being transmitted, the serial communication is initialized, and the data commands being
transmitted are considered invalid.
COMMAND 1: DISPLAY MODE SETTING COMMANDS
IK2108A provides 5 display modes setting as shown in the diagram below. As stated earlier a
command is the first one byte (b0 to b7) transmitted to IK2108A via the DI/O Pin when STB is “LOW”.
However, for these commands, Bit 5 to Bit 8 (b4 to b7) are given a value of “0”.
The Display Mode Setting Commands determine the number of segments and grids are used (14 to
10 segments, 8 to 12 grids). A display commands “ON” must be executed in order to resume display.
If the same mode setting is selected, no command execution is take place, therefore, nothing happens.
The Display Mode Setting Commands are also used to turn ON or OFF the display. Please refer to the
diagram below.
When the power is turned ON, the display is turned OFF (b3 is “0”) and the mode 111 is selected (b2
to b0 are “1”).
Display Mode Settings:
011: 12 Grids, (10 Segments)
100: 11 Grids, (11 Segments)
101: 10 Grids, (12 Segments)
110: 9 Grids, (13 Segments)
111: 8 Grids, (14 Segments)
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May 2012, Ver. 03
IK2108A
COMMAND 2: DATA SETTING COMMANDS
The Data Setting Commands executes the Data Write Mode for IK2108A. The Data Setting Command,
the bits5 and 6 (b4, b5) are given the value of “0”. , bit7 (b6) is given the value of “1” while bit8 (b7) is
given the value of “0”. Please refer to the diagram below.
When power is turned ON, bit 4 to bit 1 (b3 to b0) are given the value of “0”.
Read Data from Command Register:
1st byte
DOUT
b0
b1
b2
b3
b0-b3 of command1
b4
2nd byte
b5
b6
b7
b0-b3 of command2
b0
b1
b2
b3
b4
b0-b5 of command3
b5
b6
b7
don’t care
COMMAND 3: ADDRESS SETTING COMMANDS
Address Setting Commands are used to set the address of the display memory. The address is
considered valid if it has a value of “00H” to 2FH”. If the address is set to 30H or higher, the data is
ignored until a valid address is set. When power is turned ON, the address is set at “00H”.
Please refer to the diagram below.
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IK2108A
Display Mode and RAM Address
Data transmitted from an external device to IK2108A via the serial interface are stored in the Display
RAM and are assigned addresses. When the power is turned ON, the memory is set at “0”. The RAM
Addresses of IK2108A are given below in 8 bit unit.
dimming
GR1
GR2
GR3
GR4
GR5
GR6
GR7
GR8
GR9
GR10
GR11
GR12
00HL
04HL
08HL
0CHL
10HL
14HL
18HL
1CHL
20HL
24HL
28HL
2CHL
00HU
04HU
08HU
0CHU
10HU
14HU
18HU
1CHU
20HU
24HU
28HU
2CHU
b0
b3
b4
b7
SG5
SG8
01HU
05HU
09HU
0DHU
11HU
15HU
19HU
1DHU
21HU
25HU
29HU
2DHU
SG9
SG14
b0
b3
b4
b7
b0
b5
02Hm
06Hm
0AHm
0EHm
12Hm
16Hm
1AHm
1EHm
22Hm
26Hm
2AHm
2EHm
03
07
0B
0F
13
17
1B
1F
23
27
2B
2F
b0
b7
xxHL
xxHU
xxHL
xxHU
xxHm
xx
Lower 4
bits
Higher 4
bits
Lower 4
bits
Higher 4
bits
Lower 6 bits
8 bits
3’rd byte
4’th byte
1’st byte
DIN
SG1
SG4
01HL
05HL
09HL
0DHL
11HL
15HL
19HL
1DHL
21HL
25HL
29HL
2DHL
2’nd byte
b0 b1 b2 b3 b4 b5 b6 b7 b0 b1 b2 b3 b4 b5 b6 b7 b0 b1 b2 b3 b4 b5 b6 b7 b0 b1 b2 b3 b4 b5 b6 b7
dimming
don’t care
data for SG1-SG8
data for SG9-SG14
don’t care
Dimming Quantity Settings:
b2
b1
b0
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
Pulse
width
1/16
2/16
3/16
5/16
7/16
10/16
14/16
reserved
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May 2012, Ver. 03
IK2108A
KEY MATRIX & KEY INPUT DATA STORAGE RAM
Key Matrix consists of 10 x 3 array as shown below:
K1
K2
K3
SG1/
KS1
SG2/
KS2
SG3/
KS3
SG4/
KS4
SG5/
KS5
SG6/
KS6
SG7/
KS7
SG8/
KS8
SG9/
KS9
SG10/
KS10
Each data entered by each key (or any combination of keys) is stored as follows and read by a READ
Command, starting from the last significant bit. When the most significant bit of the data (b0) has been
read, the least significant bit of the next data (b7) is read.
K1
K3
K2
K1
K3
SG1/KS1
SG3/KS3
SG5/KS5
SG7/KS7
SG9/KS9
b0
b2
b1
K2
SG2/KS2
SG4/KS4
SG6/KS6
SG8/KS8
SG10/KS10
b3
b5
b4
x
x
x
x
x
1’st byte read
2’nd byte read
3’rd byte read
4’th byte read
5’th byte read
b6
b7
Key press=”1”, Key no press=”0” read.
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IK2108A
SCANNING AND DISPLAY TIMING
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IK2108A
SERIAL COMMUNICATION FORMAT
The following diagram shows the serial communication format.
Reception (Data/Command Write)
If data continues
STB
DI/O
CLK
b0
1
b1
2
b2
b6
3
7
b7
8
Transmission (Data Read)
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May 2012, Ver. 03
IK2108A
SWITCHING CHARACTERISTIC WAVEFORM
Switching Characteristics Waveform is given below.
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IK2108A
APPLICATIONS
Display memory is updated by incrementing addresses. Please refer to the following diagram.
Where: Command 1: Display Mode Setting
Command 2: Data Setting Command
Command 3: Address Setting Command
Data 1 to n : Transfer Display Data (48 Bytes max.)
The following diagram shows the waveforms when updating specific addresses.
Where: Command 2 -- Data Setting Command
Command 3 -- Address Setting Command
Data -- Display Data
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May 2012, Ver. 03
IK2108A
RECOMMENDED SOFTWARE PROGRAMMING FLOWCHART
Note: 1. Command 1: Display Mode Setting
2. Command 2: Data Setting Commands
3. Command 3: Address Setting Commands
4. When IC power is applied for the first time, the contents of the Display RAM are not defined:
thus, it is strongly suggested that the contents of the Display RAM must be cleared during the initial
setting.
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May 2012, Ver. 03
IK2108A
ABSOLUTE MAXIMUM RATINGS
(Unless otherwise stated, Ta=25°C, GND=0V)
Parameter
Symbol
Rating
Units
Vcc
VDD
VI
-0.5 to +18.0
-0.5 to +6.0
-0.5 to VDD+0.5
V
V
V
IOHGR
-468
mA
IOLSG
46.8
mA
Maximum Driver Output
Current/Total
ITOTAL
470
mA
Operation Temperature
Topr
-40 ~ +85
℃
Storage Temperature
Tstg
-65 ~ 150
℃
Supply Voltage
Supply Voltage
Logic Input Voltage
Driver Output Current/Pin
* Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device.
These are stress ratings only and functional operation of the device at these or any other conditions beyond those
indicated under “recommended operating conditions” is not implied.
Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
RECOMMENDED OPERATING RANGE
(Unless otherwise stated, Ta= -40 to +85°C, GND=0V)
Parameter
Symbol
Min
Typ
Max
Unit
Supply Voltage
Vcc
5.0
12.0
15.0
V
Logic Supply Voltage
VDD
3.0
5.0
5.5
V
High-Level Input Voltage
VIH
0.7VDD
.
VDD
V
Low-Level Input Voltage
VIL
0
.
0.3 VDD
V
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May 2012, Ver. 03
IK2108A
ELECTRICAL CHARACTERISTICS
(Unless otherwise stated, Vcc=5.0~18.0V, VDD=3.3~5.5V, GND=0V, Ta=-40 ~ 85°C)
Parameter
Symbol
Test Condition
Vo=1.0V
SG1/KS1 to SG10/KS10
Low-Level Output
Current
IOLSG
SG11/GR12 to SG14/GR9
display 8digitsx14segments
Vo=0.9V
SG1/KS1 to SG10/KS10
Min
Typ
Max
21.6
27
32.4
Unit
mA
31.2
39
46.8
-302.4
-378
-453.6
display 12digitsx10segments
Vo=Vcc-1.0V
R = 12.1KOhm
GR1 to GR8
High-Level Output
Current
display 8digitsx14segments
IOHGR
Vo=Vcc-1.1V
R = 12.1KOhm
GR1 to GR8
mA
-312
-390
-468
SG11/GR12 to SG14/GR9
display 12digitsx10segments
Dynamic Current
Digital Input
Current
Low-Level Digital
Output Current
Segment LowLevel Output
Current
Tolerance
IDDdyn
-
-
-
1.2
mA
IDG
-
-1
-
+1
uA
4
-
-
mA
-
-
±5
IOLDOUT
ITOLSG
VO = 0.4V
DOUT
Vo=1.0V
SG1/KS1 to SG10/KS10
SG11/GR12 to SG14/GR9
display 8digitsx14segments
Vo=0.9V
SG1/KS1 to SG10/KS10
%
-
-
±5
display 12digitsx10segments
High-Level Input
Voltage for DI/O
Low-Level Input
Voltage for DI/O
Oscillation
Frequency
K1 to K3 Pull Up
Resistor
VIH
-
0.7VDD
-
VDD
V
VIL
-
0
-
0.3VDD
V
400
500
600
kHz
22.5
30.0
37.5
KΩ
fOSC
RPU
(VDD=3.3 ~5.5V)
R = 12.1kOhm
K1 to K3
VDD =5.0V
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May 2012, Ver. 03
IK2108A
APPLICATION NOTE
IOLseg, (mA)
IOLseg vs. Rcur
80
75
70
65
60
55
50
45
40
35
30
25
20
15
10
12GRx10SEG
11GRx11SEG
10GRx12SEG
9GRx13SEG
8GRx14SEG
5
7
9
11
13
15
17
19
15
17
19
Rcur, (KOhm)
fosc (KHz)
fosc vs. Rcur
1300
1200
1100
1000
900
800
700
600
500
400
300
200
5
7
9
11
13
Rcur (KOhm)
1. The graph of IOLSG vs. RCUR is given for the case when only one segment is turn on.
Choosing the external resistor RCUR for the setting IOLSG, make sure, that current
IOHGR=(number of segments)*IOLSG ≤ 390mA
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May 2012, Ver. 03
IK2108A
2. The cell of Display Memory has a dead time zone. If the software program is not correct, it is
possible the blinking of display. The blinking frequency for the single segment is:
MAX
FBLINK

FCOMMAND 2
F
(1  0.5 * OSC ) , (less value is better),
256 * G
FCLK
where FCOMMAND2 – frequency of the use of the command2 (Write Data to Display Memory);
G– number of grids in used mode;
FOSC – frequency of internal OSC;
FCLK – clock frequency.
So, main rule for update the Display Memory is do it if it really need. Don’t do it continually with
high speed, but if it something like movie you can. Or another way is turn off the display while the
command of Write Data to Display Memory is executed.
3. To determine the Average Consumption Current of IK2108A, you should use the next formula (the
current value during key scan period is ignored as this value is very small in compare with
segment’s current):
Itotal(avrg) = (N* IOLSG *Dimming)*(M/(M+1)),
where N is segment’s number;
M is grid’s number;
Dimming is Dimming value (see p.7);
IOLSG is output segment’s current (see table Electrical Characteristics).
Therefore different display configurations will have different current consumption. Let’s consider the
maximum case, when Dimming is 14/16 and all segments and grids are used:
8 grids x 14 segments display: Itotal(avrg)=(14*27mA(typical value)*14/16)*(8/9)=294mA;
12 grids x 10 segments display: Itotal(avrg)=(10*39mA(typical value)*14/16)*(12/13)=315mA.
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May 2012, Ver. 03
IK2108A
APPLICATION CIRCUIT
(FOR 8GRID x 14SEGMENT DISPLAY)
+5V
+15V
C2
1~10k
12.1k
MCU
K1
K2
C1
R
S1
R
S2
R
S3
R
S4
R
S5
R
S6
R
S7
GR1
G1
GR2
G2
CLK
GR3
G3
STB
GR4
G4
K1
GR5
G5
GR6
G6
K3
GR7
G7
VDD
GR8
G8
GND
VCC
K2
IK2108A
G1
G2
G3
G4
G5
G6
G7
G8
SG1/KS1
SG14/GR9
S14
R
SG2/KS2
SG13/GR10
S13
R
SG3/KS3
SG12/GR11
S12
R
SG4/KS4
S11
R
SG11/GR12
R
SG5/KS5
SG10/KS10
S10
SG6/KS6
SG9/KS9
S9
R
R
SG8/KS8
S8
SG7/KS7
DIGIT1
DIGIT2
DIGIT3
DIGIT4
DIGIT5
DIGIT6
DIGIT7
DIGIT8
S14 SEG14
S13 SEG13
S12 SEG12
S11 SEG11
S10 SEG10
S9 SEG9
S8 SEG8
S7 SEG7
S1
D
S2
D
S3
D
S4
D
S5
D
S6
D
S7
D
S8
D
S9
D
S10
D
8-GRID x 14 SEGMENT
(COMMON ANODE)
K3
RCUR
DI/O
S6 SEG6
S5 SEG5
S4 SEG4
S3 SEG3
S2 SEG2
S1 SEG1
K1
K2
K3
Recommend value:
C1&C2
0.1uF-ceramics
R
160Ohm 0.5W (if one diode is connected)
110Ohm 0.25W (if two diodes are connected)
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May 2012, Ver. 03
IK2108A
COMMON ANODE TYPE LED PANEL
SEG1
SEG2
a
COM/DIGITAL (GRID)
b
a
c
SEG3
SEG4
f
d
b
g
e
SEG5
SEG6
SEG7
e
f
g
c
d
h
h
SEG8
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May 2012, Ver. 03
IK2108A
Package Dimension
LQFP-32
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May 2012, Ver. 03
IK2108A
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May 2012, Ver. 03