ETC 09-ELM205-ST

Advanced Printing Systems
ELM 205
Technical reference
ELM 205
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Technical reference -
Rev. G -
1
Advanced Printing Systems
1.
Introduction
1.1.
ELM 205 Series
The ELM 205 printer has been designed to be the smallest, wide low voltage range (from 2.7v
to 8.5v), and high efficiency (20% less than standard 5v mechanisms) easy loading printer on
its market. The unique easy loading APS concept makes the ELM 205 an ultra compact, reliable
and cost-effective mechanism. The rubber roller can be separated from the mechanism and
fixed to the customer’s door allowing for very easy integration.
The patented locking system of the rubber roller onto the chassis and easy opening lever makes
the door position and rotation axe independent of the cover position, giving the customer a total
freedom when designing his housing. Finally, the ergonomic centered paper path allows
uniform and aesthetic housing design. Finally no access to the cover’s sides is required to open
the door.
1.2.
ELM 205 features
• Patented Easy loading and Easy Door Opening System
• Ultra compact design (width is 66.7, depth 22.4 mm)
• Up to 90 mm/s printing speed
• Ultra light (35g)
• Starting operating voltage (logic and dots) from 2.7v up to 8.5v
• High resolution printing (8 dots/mm)
• Life of 100 millions pulses, 50 kms
• Low consumption
• Low noise due to its technology (thermal)
• ESD Grounding clip on printhead (ELM205-HS-VRF only)
ELM 205
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Technical reference -
Rev. G -
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Advanced Printing Systems
1.3.
Revision history
Rev.
Date
Page
Revision item
A
12/Nov/98
-
Preliminary
B
07/Jun/99
-
Easy Door Opening System + LV/HS Versions
C
02/Jul/99
-
Protection thickness increase
change) + connector pinout HS-LV
D
18/Oct/99
-
Mechanical Drawings information
E
05/Jan/00
-
FPC for LV and HS versions same as ST
F
12/Oct/00
-
Updated photo and overall dimens. drawings
G
14/Jun/01
-
Added ESD clip option on ELM205-HS-VRF
This manual provides complete information about ELM 205 thermal printer
mechanism. Further information is available under request such as high speed
printing applications and reliability figures.
A.P.S. reserves the right to make changes without notice to the product to
improve reliability, functions or design. A.P.S. does not assume any liability
arising out of the application or use of the product or circuit described herein.
ELM 205
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Technical reference -
Rev. G -
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(drawing
Advanced Printing Systems
TABLE OF CONTENTS
1.
1.1.
1.2.
1.3.
INTRODUCTION....................................................................................................................................................................... 2
ELM 205 SERIES ...................................................................................................................................................................... 2
ELM 205 FEATURES ................................................................................................................................................................ 2
REVISION HISTORY...................................................................................................................................................................... 3
2.
GENERAL CHARACTERISTICS........................................................................................................................................... 5
3.
THERMAL PRINTHEAD AND PRINTING CONFIGURATION .................................................................................... 6
3.1.
3.2.
3.3.
3.4.
3.5.
3.6.
3.7.
4.
4.1.
4.2.
OUTLINES................................................................................................................................................................................... 6
MAXIMUM CONDITIONS AT 25°C.............................................................................................................................................. 6
TYPICAL PRINTING CONDITIONS .................................................................................................................................................. 7
GENERAL PRINTING CONDITIONS................................................................................................................................................. 7
OPERATION PRECAUTIONS.......................................................................................................................................................... 8
ELECTRICAL CHARACTERISTICS ................................................................................................................................................. 8
THERMISTOR ............................................................................................................................................................................10
STEPPER MOTOR..................................................................................................................................................................10
STEPPER MOTOR TIMING...........................................................................................................................................................10
P APER FEED SPEED VERSUS VOLTAGE ........................................................................................................................................11
5.
HOW TO OPTIMIZE SPEED CONSUMPTION AND MAXIMUM PEAK CURRENT.............................................11
6.
SENSORS...................................................................................................................................................................................13
6.1.
6.2.
DOOR OPEN ..............................................................................................................................................................................13
END OF PAPER SENSOR..............................................................................................................................................................13
7.
PIN OUT ASSIGNMENT........................................................................................................................................................14
8.
LIFE UNDER STANDARD PRINTING CONDITIONS....................................................................................................15
9.
MECHANICAL & HOUSING ...............................................................................................................................................15
9.1.
9.2.
9.3.
DESIGNING THE DOOR ...............................................................................................................................................................15
THE EASY DOOR OPENING SYSTEM ..........................................................................................................................................15
GENERAL MECHANICAL SPECIFICATION ....................................................................................................................................15
10.
ORDERING CODE .................................................................................................................................................................16
ELM 205
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Technical reference -
Rev. G -
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Advanced Printing Systems
2.
General characteristics
ITEM
Printing Method
ELM 205
Thermal dot line printing
Number of dots/line
384
Dots density (dot/mm)
8
Printing Width (mm)
48
Paper Width (mm)
58 +0/-1
Paper feed pitch (mm)
0.125
Paper Feed tension (g)
50 or more
Paper Hold tension (g)
80 or more
Dimension WxDxH (mm)
68.2 x 22.4 x 15
Weight (g)
35
Head temperature detection
Thermistor
Head-up detection
Photo-interruptor (gathered with the paper
end sensor)
Paper end detection
Photo-interruptor
ELM205-LV Dots : 2.7-7.2/Logic: 2.7-5.25
ELM205-ST Dots :
4.5-8.5/Logic :4.755.25
ELM205-HS Dots : 4.5-8.5/Logic : 2.7-5.25
Operation voltage range (V)
Current consumption (A)
Recommended Paper
At printing:
5 V: 1.9 A (Head)
(64 dots ON) 0,5A (Motor)
5V: 50 mA (Head)
At paper feeding : 5V:
0,5A(Motor)
5V: <100uA (Head)
KF50-HDA or equivalent
Operating temperature range (°C)
Operating humidity (RH%)
0/+50
20-85 (no condensation)
Storage temperature range (°C)
Storage humidity (RH%)
ELM 205
-
-25/+70
10-90 (no condensation)
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Rev. G -
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Advanced Printing Systems
3.
Thermal Printhead and printing configuration
3.1.
Outlines
Heat element structure
Number of heat elements
Heat element pitch
Print width
Total width
Average resistance
3.2.
2 heaters/dot
384 dots
0.125 mm
48 mm (centered on paper)
54 mm
LV - 123 Ohms +/-4% (2.7v-7.2v low voltage)
ST - 142 Ohms +/- 4% (5v standard)
HS - 176 Ohms +/-4% (7.2v high speed)
Maximum conditions at 25°C
MAXIMUM
CONDITIONS
ITEM
UNIT
LV
ST
HS
Supply energy (25°C)
0.26
0.7
0.2
mJ/dot
Print Cycle (25°C)
2.5
5.0
1.25
ms/line
Supply voltage
7.2
8.5
8.5
volts
Logic voltage
7
volts
Head Temperature
65
°C
192
dots
Number of dots
simultaneously1
to
be
energized
1/ If energy above the maximum at the indicated printing speed is applied to one dot, the print
quality of this dot may be affected (usually by making a “light” print-out).
2/ If the print cycle is less than that the one indicated above, then the maximum supply energy
value is decreased. For these applications, please contact APS for further information.
3/ In the case of double-ply paper or special low energy paper, please contact APS for more
information.
1
This condition satisfies the print density as defined in section 3.3
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Advanced Printing Systems
3.3.
Typical printing conditions
Item
Symbol
Electrical conditions
ST
5.0
HS
7.2
Unit
V
Supply voltage
Vh
LV
3.6
Power consumption
Po
0.07
0.123
0.24
W/dot
64
dots
S.L.T
2.5
5.0
1.25
ms/line
fired
at the
0.17
0.36
0.16
mJ/dot
5°
same
(2.28)
(2.96)
(0.67)
ms
C
time
0.15
0.31
0.13
mJ/dot
25°
(2.01)
(2.53)
(0.54)
ms
C
0.13
0.28
0.11
mJ/dot
45°
(1.74)
(2.28)
(0.46)
ms
C
1.6
1.9
2.4
A
Print cycle
Energy consumption
Eo
(on time)
(Ton)
Supply current
Io
The print optical density is then 1.0 minimum with a maximum variation of 0.3. This
measurement is done at the full black pattern by Macbeth densitometer RD-914. Full black
pattern is defined as all dots printing pattern (100% black area) printed under correct paper
speed.
3.4.
General printing conditions
The following formula allows to calculate the heating time Ton depending on driving voltage
VH:
2
E 0 = * (N * R com + R av + R ic + R l )
=
T on
E0
2
P0
V H * R av
Where:
E0 is the nominal energy
VH is the driving voltage
Rav is the average resistance
N is the number of dots energized simultaneously
Rcom is the common resistance (0.05 Ohm)
Ric is the driver saturated resistance (10 Ohms)
Rl is the lead resistance (10 Ohms)
ELM 205
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Rev. G -
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Advanced Printing Systems
3.5.
Operation precautions
1/ When performing continuous printing, the supply energy should be reduced so that the
substrate temperature monitored through the thermistor will remain below 65°C.
2/ When the printhead operation is finished, the print supply voltage should be reduced to the
ground level and remain there until next printhead operation.
3/ If sticking sound is heard during printing, adjust the paper feed speed or pulse to avoid this
mechanical resonance.
4/ To avoid surge and voltage drops across power wires, Vh and Gnd cable length should be
less than 100 mm, and 47uF aluminum capacitor is required between Vh and Gnd at controller
board side.
5/ Make sure that the paper does not have characteristics which could affect the printhead life,
such as high abrasivity, too low sensitivity or abnormal chemicals.
3.6.
Electrical Characteristics
The following chart gives the timing for driving the printhead:
TvCLK
Cloc
Tsetup
Thold Din
Data
Tsetup LAT
Thold
L
\Latch
Tsetup
Td0
ST
Strobe
Tw
L
Driver
O
Td0
!!! CAUTION!!!
To prevent any dot element damage, at power up make sure that logic voltage is present
simultaneously or before Vbat. At power down make sure that Vbat is at 0v before removing
logic voltage.
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Advanced Printing Systems
The following table gives all the printhead electrical characteristics:
ITEM
SYMBOL
MINI
TYP.
MAXI
UNIT
V
Print voltage
VH
-
5.0
Logic voltage
Vdd
5.00
Logic current
Input voltage (High)
Input voltage (Low)
Data input current (DI) High
Data input current (DI) Low
STB 1 to 6 input current (High)
STB 1 to 6 input current (Low)
Clock input current (High)
Clock input current (Low)
Latch input current (High)
Latch input current (Low)
Data out output voltage (High)
Data out output voltage (Low)
Output voltage (driver out)
Clock frequency
Clock width
Data setup time
Data hold time
Latch width
Latch setup time
Idd
VIH
VIL
ILHDI
ILLDI
IIHSTR
IILSTR
ILH CLK
ILL CLK
IIH LAT
IIL LAT
VDOH
VDOL
VOL
fCLK
twCLK
tsetupDI
tholdDI
twLAT
tsetup
LAT
tholdLAT
tdDO
tsetup
STB
tdo
LV/HS = 2.7
ST = 4.75
0.8vdd
0
4.45
30
30
10
100
200
ST/HS = 8.5
LV = 7.2
5.25
1.0
-
48
vdd
0.2vdd
0.5
-0.5
30
-0.5
3
-3
3
-3
0.05
8
-
mA
V
V
uA
uA
uA
uA
uA
uA
uA
uA
V
V
V
MHz
ns
ns
ns
ns
ns
50
300
-
120
-
ns
ns
ns
-
-
5
us
Latch hold time
Data out delay time
STR setup time
Driver out delay time
V
Note: 1/The first bit of data (dot 1) entered is the first bit of data printed (FIFO), left side of
TPH, top view (gearing side of the printer).
2/ STB 1 to STB 6 are driving one sixth of the printhead, starting from dot 1.
ELM 205
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Technical reference -
Rev. G -
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Advanced Printing Systems
3.7.
Thermistor
When performing continuous printing, it is recommended that the supply energy be reduced so
that the substrate temperature monitored through the thermistor will remain below the maximum
temperature shown in section 3.2.
The thermistor specification is the following:
- R25, resistance at 25°C:
30
KOhms +/- 5% at 25°C
- B value:
3950 KOhms +/- 2%
- Operating temperature:
-20°C to +80°C
- Time constant:
Max. 30 sec (in the air)
Then the resistance value, R, versus temperature, T (in °C), is given by the formula:
1
1
R( T ) = R25* e B*( T+273 - 25+273 )
4.
Stepper motor
4.1. Stepper motor Timing
The paper feed pitch for stepper motor is 2 steps for one dotline (0,125 mm). For good print
quality it is advised to keep the current into the windings between two successive dotlines.
The timing diagram is then as follows:
PHASE 1
PHASE 2
PHASE 3
PHASE 4
1
DOTLINE
2
3
There are four different positions for the stepper motor. The driving is bipolar and can be
achieved with circuits like Rohm BA6845FS, Sanyo LB1836 or LB1838 or Hitachi HA13421.
Please refer to the IC’s data sheet for further information. It is recommended not to exceed 0.2v
like voltage drop in the stepper motor driver circuit.
Coil resistance is 12 Ohms, rated current is 300 mA (5 volts) per phase while feeding at
10mm/s.
In case of high voltage or continuous printing application, contact APS for current application
circuitry.
ELM 205
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Technical reference -
Rev. G -
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Advanced Printing Systems
4.2.
Paper feed speed versus voltage
The following chart gives the maximum paper feed speed versus the stepper motor voltage
ELM205
PAPER FEED
Duty Cycle (%)
Voltage
2.7
3
3.3
3.6
4
4.5
5
5.5
6
6.5
7
7.5
8
8.5
ELM205-LV/ST/HS
23
35
37
40
47
50
56
59
62
68
72
80
85
90
ELM205-LV/ST/HS
100
100
100
100
100
80
60
50
40
35
30
25
20
15
In order to avoid stepper motor overheat, it is strongly advised to respect the maximum
ON/OFF duty cycle as indicated above. Note that the maximum period for the ON time is 30
seconds (when the duty cycle is not 100%).
Example : at 7 volts, the duty cycle must be less than 30%. So the maximum ticket length at the
maximum speed is 30s at 72mm/s so 2.16 meters. Then the printer must rest for 70/30*45s = 70
seconds.
5.
How to optimize speed consumption and maximum peak
current
The printing speed is always a compromise between 3 parameters :
•
•
•
Paper feed speed (function of voltage)
Head activation time (function of voltage)
Maximum peak current available (function of voltage and maximum number of dots
simultaneously activated)
For a given voltage, and a maximum current available, it is easy to determine the maximum
paper feed speed (MaxPFS), as indicated on the above chart. Then if the two others parameters
are not limiting this speed this will also be the printing speed (MaxPS).
ELM 205
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Rev. G -
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Advanced Printing Systems
MaxPFS gives a time (by inverting) called SLT (scanning line time). In this time, the head must
be activated. If this time is not long enough, MaxPS will be subsequently affected.
Then, the way of driving the head is a critical point in the thermal printing application. There
are basically two ways of limiting the current in the head.:
1. Divide the head into fixed blocks (by 64 dots for example) and use the strobe lines to
control the blocks to be activated. In this case. It is easy to implement but the printing speed
will be very slow because the MaxPS will be the invert of the activation time times the
number of blocks the head is divided in.
Example: at 6 volts with the ELM205ST, the activation time is 2.53ms*(25/36) =
1.76ms. If the maximum current available for the head is 2.4A, the maximum number of
dots to be simultaneously activated will be 2.4Amps/(6volts/160Ohms)=64 dots. So the
number of activation per SLT will be 384/64=6, giving a SLT of 6*1.76ms=10.6ms.
then MaxPS will be 1/(8*10.6ms) = 11.8 mm/s. And MaxPFS is 62mm/s. So there is a
big margin and the printing speed is relatively slow.
2. Divide the head dynamically, by counting the number of dots actually activated. The
software is counting while loading the printhead, the actual number of “black” dots. When
the number of black dots has reached the maximum value (in this example the value will be
64) the software will fill the remaining dots with “0” and activates the strobes line. Doing
so the activation will be always done with the maximum number of black dots allowed, so
optimizing the number of times the head needs to be activated. Printing standard text, the
average number of black dots is usually less than 64 and sometimes reach 128.
Example: In the same conditions of the previous example, MaxPS will be
multiplied by 6, or sometimes by 3. Let take that 30% of the lines contains from 64 to
128 black dots, the average MaxPS will be (62(#))*0.7 + (11.8*3)*0.3 = 60.2 mm/s,
getting very close to the MaxPFS, and optimizing all the parameters.
(#) : we take 62 because 11.8*6 =70.8 > MaxPFS.
ELM 205
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Technical reference -
Rev. G -
12
Advanced Printing Systems
6.
Sensors
6.1.
Door open
In order to optimize and decrease the number of elements of the ELM 205, the opto sensor
performs dual functions - door open and end of paper detection. The shape and distance from
the opto sensor to the paper is designed in a way that as soon as the door is opened, the distance
between the paper and the sensor increases, and this causes the end of paper sensor is to
trigger.
6.2.
End of paper sensor
ELM 205 has an end of paper sensor achieved by a photo-transistor. Arrange the circuitry so
that no energy is applied to the head when there is no paper. If the head is energized when there
is no paper and the head is in the down position, then both roller and head may be strongly
damaged.
General specifications:
ITEM
Forward current
photodiode
Reverse current
Output dark current
Light current
Symbol
IF
CONDITIONS
VF = 5v± 5%
Min
-
Typ
20
Max
30
Unit
mA
IR
Vr= 5V
VCE= 10V
VCE = 5V
IF = 20mA
VCE = 2 V
IC = 0.1 mA
RL = 1KΩ
90
-
10
0.2
660
uA
uA
uA
-
30
-
us
-
25
-
us
ICEO
IL
Time
TR
Fall time
TF
One possible interfacing is as follows:
+5v
+5v
180 R
27 K
ELM 205
to Analog CPU Port
Vpaper < 2.5v
V no paper > 4.5v
ELM 205
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Technical reference -
Rev. G -
13
Advanced Printing Systems
7.
Pin out assignment
One flexy cable is gathering all signals. The pitch at the end of the flexy is 1mm.
FPC connector can be : JST 27FMN-BMT-TF
ELM205-ST-LV-HS
Pin Number
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
Signal name
CO
VF
L-GND
VH
VH
DI
STB6
STB5
STB4
P-GND
P-GND
P-GND
P-GND
TM
STB3
STB2
STB1
Vdd
CLK
\LAT
DO
VH
VH
SM4
SM3
SM2
SM1
Function
Collector of photo-transistor
Anode of photo-sensor
Gnd for logic
Dotline voltage
Dotline voltage
Data input
Sixth strobe
Fifth strobe
Fourth strobe
Gnd for dotline
Gnd for dotline
Gnd for dotline
Gnd for dotline
Thermistor first terminal (second is Gnd)
Third strobe
Second strobe
First strobe
Logic voltage
Serial clock
Latch
Data output
Dotline voltage
Dotline voltage
Fourth phase of stepper motor
Third phase of stepper motor
Second phase of stepper motor
First phase of stepper motor
NOTE - For pin #1 position, please refer to the drawings at the end of this document
- In ELM 205-HS-VRF a ESD grounding clip is provided to connect GND (pins 10, 11,
12 and 13) to printhead metal heat sink
ELM 205
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Technical reference -
Rev. G -
14
Advanced Printing Systems
8.
Life under standard printing conditions
Life is defined as a change in the resistance value of any dots equal to or exceeding 15% from
their initial value. Head temperature shall not exceed the maximum 60°C with thermistor
reading.
Then: - Pulse life :
100.106 Pulses
- Abrasion life:
50 kms
9.
Mechanical & Housing
The 3 versions of the ELM are mechanically identical (fixing points, dimensions)
9.1.
Designing the door
The function of the door is to bring the rubber roller to the chassis’ window entrance and to
make it follow the external path of the chassis’ window.
Given the shape of the chassis and the example in the mechanical drawing section (end of the
specification), the cover is fairly easy to design.
In order to keep a good alignment, it is strongly advised to keep the rubber roller fully floating
inside the cover to compensate any tolerance problem inside the cover.
Moreover this play must be present in order to allow the rubber roller to follow the shape of
the chassis.
9.2.
The Easy Door Opening System
Because the rubber roller is only referenced to the chassis and has no dependence on the cover,
the mechanism is very reliable. To achieve this reliability, the rubber roller must be strongly
locked inside the chassis.
To avoid any twist, and mechanical stress on the cover and more generally on the customer
plastic, so increasing the reliability and quality, APS developed a unique and patented feature
to ease the opening of the door, that makes the mechanism very easy to open, and does not
require any access to the cover’s sides, giving more flexibility and ergonomics to the customer
design.
This is achieved by clipping an internal lever inside the cover, that pushes symmetrically on
both sides of the mechanism. So the mechanism’s shape has been optimized to concentrate the
effort locally and always refer this effort to the chassis.
Doing so there is no need to have access to the cover side, giving more freedom to deign the
cover, and allowing to reduce the width of the unit.
Please contact APS to obtain the application notes and for any assistance in designing the
lever.
9.3.
General mechanical specification
(See attached drawing)
ELM 205
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Technical reference -
Rev. G -
15
Advanced Printing Systems
10.
Ordering code
ELM 205 Low Voltage (from 2.7v):
ELM 205 Standard 5v:
ELM 205 High Speed (80mm/s):
ELM 205 HS with ESD grounding clip:
ELM 205
-
ELM 205-LV
ELM 205-ST
ELM 205-HS
ELM 205-HS-VRF
Technical reference -
Rev. G -
16