Samsung SCX-4725FN, SCX-4725F Service Manual
DIGITAL LASER MFP The keynote of Product
Manual
SERVICE
- Machine Life: 50,000Pages
- Cpu: Chorus M
- Device Memory: 32MB
- Resolution: 1200x1200dpi
- Option: N/A
- Printing Speed: 24ppm(A4, LTR)
- Print Language: PCL
- Path Type: C-Path
- Cassette Capa.: 250sheets
- Outlet Stacking Capa.: 100sheets
- Toner Cartridge: initial(1.5K), sales(3K)
- ADF Capacity: 30sheets
- Scan Method: 600 dpi Color CIS
- Copy Speed: SDMC: 22Cpm/Ltr,
MDMC: 7Cpm/Ltr
- Interface: USB2.0
Basic Model :SCX-4725FN
SCX-4725FN Series
SCX-4725FN/XEP
Contents
1. Precautions
1.1 Safety Warning 1-1
1.2 Caution for safety
1-2
1.3 ESD Precautions
1-5
1.4 Super Capacitor or Lithium Battery Precautions
1-5
2. Product spec and feature
2.1 Product Specifications 2-1
2.1.1 Product Overview
2-1
2.1.2 Specitications
2-2
2.1.3 Model Comparison Table
2-9
2.2 System Overview
2-10
2.2.1 System Layout
2-10
2.2.2 Engine H/W Specification
2-14
2.2.3 Develope Process
2-21
2.2.4 Sanner Part
2-22
2.2.5 OPE(Operational Panel Equipment)
2-24
2.2.6 SMPS & HVPS
2-25
2.2.7 FUSER AC POWER CONTROL
2-27
3. Disassembly and Reassembly
3.1 General Precautions on Disassembly 3-1
3.2 MP Tray
3-2
3.3 Pick Up Roller
3-3
3.4 Front Cover
3-3
3.5 Cassette Tray
3-4
3.6 Rear Cover
3-5
3.7 Right Cover
3-6
Continued
3.8 Left Cover 3-7
3.9 Scan Ass'y
3-8
3.10 ADF Housing
3-9
3.11 OPE Unit
3-11
3.12 Platen Housing
3-12
3.13 Middle Cover
3-14
3.14 HVPS
3-15
3.15 Main PBA
3-16
3.16 RX Drive
3-17
3.17 Fuser Unit
3-18
3.18 Engine Shield (With LIU PBA, SMPS)
3-21
3.19 LSU
3-22
3.20 Paper Path Frame
3-23
3.21 CRUM Harness
3-25
4. Troubleshooting
4.1 Alignment and Adjustments 4-1
4.1.1 User Mode
4-1
4.1.2 Tech Mode and Setting
4-4
4.1.3 Control Panel
4-13
4.1.4 LCD Status Error Message
4-15
4.1.5 Engine Test Mode
4-17
4.1.6 Paper Path and Clearing Paper Jams
4-19
4.2 Troubleshooting
4-25
4.2.1 Checking Symptoms
4-25
4.2.2 Bad discharge
4-28
4.2.3 Set Malfunction – Causes and Solutions
4-32
4.2.4 Bad Software Environment
4-36
4.2.5 Bad image
4-40
4.2.6 Fax & Phone Problems
4-47
4.2.7 Copy Problems
4-51
Continued
4.2.8 Scanning Problems – Causes and Solutions 4-53
4.2.9 Toner Cartridge Service
4-54
4.2.10 Software Problems – Causes and Solutions
4-56
4.2.11 Windows Problems
4-61
4.2.12 SyncThru Installation Problems
4-62
5. Exploded Views & Parts List
5.1 Main 5-2
5.2 Cover Housing
5-4
5.3 Front Cover
5-6
5.4 Rear Cover
5-8
5.5 Frame Ass'y
5-10
5.6 ADF Ass'y
5-12
5.6-3-2 ADF Ass'y Part (Additional)
5-13
5.7 Platen Cover Ass'y
5-16
5.8 Platen Ass'y
5-18
5.9 OPE Unit
5-20
5.10 RX Drive Unit
5-22
5.11 MP Tray
5-24
5.12 Fuser Unit
5-26
5.13 Paper Path Ass'y
5-28
5.14 Pick UP Unit
5-30
6. System Diagram
6.1 Block Diagram 6-1
6.1 Connection Dia ram
6-2
Continued
7. Reference Information
7.1 Troubleshooting Tool 7-1
7.2 Acronyms and Abbreviations
7-2
7.3 Selecting printer locations
7-4
7.4 Sample Tests Patterns
7-5
Precautions
Samsung Electronics
Service Manual
1-1
1
1
1. Precautions
In order to prevent accidents and to prevent damage to the equipment please read the precautions listed
below carefully before servicing the printer and follow them closely.
1.1 Safety W arning
(1) Only to be serviced by appropriately qualified service engineers.
High voltages and lasers inside this product are dangerous. This printer should only be serviced by a suitably
trained and qualified service engineer.
(2) Use only Samsung replacement parts
There are no user serviceable parts inside the printer. Do not make any unauthorized changes or
additions to the printer, these could cause the printer to malfunction and create electric shock or fire hazards.
(3) Laser Safety Statement
The Printer is certified in the U.S. to conform to the requirements of DHHS 21 CFR, chapter 1 Subchapter J for
Class 1(1) laser products, and elsewhere, it is certified as a Class I laser product
conforming to the requirements of IEC 825. Class I laser products are not considered to be hazardous. The
laser system and printer are designed so there is never any human access to laser radiation above a Class I
level during normal operation, user maintenance, or prescribed service condition.
Warning >> Never operate or service the printer with the protective cover removed from Laser/Scanner assembly . The
reflected beam, although invisible, can damage your eyes. When using this product, these basic safety
pre-cautions should always be followed to reduce risk of fire, electric shock, and injury to persons.
CAUTION - INVISIBLE LASER RADIATION
WHEN THIS COVER OPEN.
DO NOT OPEN THIS COVER.
VORSICHT - UNSICHTBARE LASERSTRAHLUNG,
WENN ABDECKUNG GEÖFFNET.
NICHT DEM STRAHL AUSSETZEN.
ATTENTION - RAYONNEMENT LASER INVISIBLE EN CAS
D’OUVERTURE. EXPOSITION DANGEREUSE
AU FAISCEAU.
ATTENZIONE - RADIAZIONE LASER INVISIBILE IN CASO DI
APERTURA. EVITARE L’ESPOSIZIONE AL
FASCIO.
PRECAUCION - RADIACION LASER IVISIBLE CUANDO SE ABRE.
EVITAR EXPONERSE AL RAYO.
ADVARSEL. - USYNLIG LASERSTRÅLNING VED ÅBNING, NÅR
SIKKERHEDSBRYDERE ER UDE AF FUNKTION.
UNDGÅ UDSAETTELSE FOR STRÅLNING.
ADVARSEL. - USYNLIG LASERSTRÅLNING NÅR DEKSEL
ÅPNES. STIRR IKKE INN I STRÅLEN.
UNNGÅ EKSPONERING FOR STRÅLEN.
VARNING - OSYNLIG LASERSTRÅLNING NÄR DENNA DEL
ÄR ÖPPNAD OCH SPÄRREN ÄR URKOPPLAD.
BETRAKTA EJ STRÅLEN. STRÅLEN ÄR FARLIG.
VARO! - AVATTAESSA JA SUOJALUKITUS OHITETTAESSA
OLET ALTTIINA NÄKYMÄTTÖMÄLLE LASER-
SÄTEILYLLE ÄLÄ KATSO SÄTEESEEN.
Samsung Electronics
Service Manual
Precautions
1-2
1.2 Caution for safety
1.2.1 Toxic material
This product contains toxic materials that could cause illness if ingested.
(1) If the LCD control panel is damaged it is possible for the liquid inside to leak. This liquid is toxic. Contact with the skin
should be avoided, wash any splashes from eyes or skin immediately and contact your doctor . If the liquid gets into
the mouth or is swallowed see a doctor immediately .
(2) Please keep toner cartridges away from children. The toner powder contained in the toner cartridge may be harmful
and if swallowed you should contact a doctor .
1.2.2 Electric Shock and Fire Safety Precautions
Failure to follow the following instructions could cause electric shock or potentially cause a fire.
(1) Use only the correct voltage, failure to do so could damage the printer and potentially cause a fire or electric
shock.
(2) Use only the power cable supplied with the printer. Use of an incorrectly specified cable could cause the cable
to overheat and potentially cause a fire.
(3) Do not overload the power socket, this could lead to overheating of the cables inside the wall and could lead to
a fire.
(4) Do not allow water or other liquids to spill into the printer, this can cause electric shock. Do not allow paper
clips, pins or other foreign objects to fall into the printer these could cause a short circuit leading to an electric
shock or fire hazard..
(5) Never touch the plugs on either end of the power cable with wet hands, this can cause electric shock. When
servicing the printer remove the power plug from the wall socket.
(6) Use caution when inserting or removing the power connector. The power connector must be inserted com-
pletely otherwise a poor contact could cause overheating possibly leading to a fire. When removing the power
connector grip it firmly and pull.
(7) Take care of the power cable. Do not allow it to become twisted, bent sharply round corners or otherwise
damaged. Do not place objects on top of the power cable. If the power cable is damaged it could overheat and
cause a fire or exposed cables could cause an electric shock. Replace a damaged power cable immediately,
do not reuse or repair the damaged cable. Some chemicals can attack the coating on the power cable,
weakening the cover or exposing cables causing fire and shock risks.
(8) Ensure that the power sockets and plugs are not cracked or broken in any way. Any such defects should be
repaired immediately. Take care not to cut or damage the power cable or plugs when moving the machine.
(9) Use caution during thunder or lightening storms. Samsung recommend that this machine be disconnected from
the power source when such weather conditions are expected. Do not touch the machine or the power cord if it
is still connected to the wall socket in these weather conditions.
(10) Avoid damp or dusty areas, install the printer in a clean well ventilated location. Do not position the machine
near a humidifier. Damp and dust build up inside the machine can lead to overheating and cause a fire.
(1 1) Do not position the printer in direct sunlight. This will cause the temperature inside the printer to rise possibly
leading to the printer failing to work properly and in extreme conditions could lead to a fire.
(12) Do not insert any metal objects into the machine through the ventilator fan or other part of the casing, it could
make contact with a high voltage conductor inside the machine and cause an electric shock.
Precautions
Samsung Electronics
Service Manual
1-3
1.2.3 Handling Precautions
The following instructions are for your own personal safety, to avoid injury and so as not to damage the printer
(1) Ensure the printer is installed on a level surface, capable of supporting its weight. Failure to do so could cause
the printer to tip or fall.
(2) The printer contains many rollers, gears and fans. T ake great care to ensure that you do not catch your fingers,
hair or clothing in any of these rotating devices.
(3) Do not place any small metal objects, containers of water, chemicals or other liquids close to the printer which if
spilled could get into the machine and cause damage or a shock or fire hazard.
(4) Do not install the machine in areas with high dust or moisture levels, beside on open window or close to a
humidifier or heater. Damage could be caused to the printer in such areas.
(5) Do not place candles, burning cigarettes, etc. on the printer, these could cause a fire.
1.2.4 Assembly / Disassembly Precautions
Replace parts carefully, always use Samsung parts. Take care to note the exact location of parts and also
cable routing before dismantling any part of the machine. Ensure all parts and cables are replaced correctly.
Please carry out the following procedures before dismantling the printer or replacing any parts.
(1) Check the contents of the machine memory and make a note of any user settings. These will be erased if the
mainboard is replaced.
(2) Ensure that power is disconnected before servicing or replacing any electrical parts.
(3) Disconnect printer interface cables and power cables.
(4) Only use approved spare parts. Ensure that part number, product name, any voltage, current or temperature
rating are correct.
(5) When removing or re-fitting any parts do not use excessive force, especially when fitting screws into plastic.
(6) Take care not to drop any small parts into the machine.
(7) Handling of the OPC Drum
- The OPC Drum can be irreparably damaged if it exposed to light.
Take care not to expose the OPC Drum either to direct sunlight or to fluorescent or incandescent room
lighting. Exposure for as little as 5 mins can damage the surface’s photoconductive properties and will result
in print quality degradation. Take extra care when servicing the printer. Remove the OPC Drum and store it in
a black bag or other lightproof container . Take care when working with the covers(especially the top cover)
open as light is admitted to the OPC area and can damage the OPC Drum.
- Take care not to scratch the green surface of OPC Drum Unit.
If the green surface of the Drum Cartridge is scratched or touched the print quality will be compromised.
Samsung Electronics
Service Manual
Precautions
1-4
1.2.5 Disregarding this warning may cause bodily injury
(1) Be careful with the high temperature part.
The fuser unit works at a high temperature. Use caution when working on the printer. Wait for the fuser to cool
down before disassembly.
(2) Do not put finger or hair into the rotating parts.
When operating a printer, do not put hand or hair into the rotating parts (Paper feeding entrance, motor, fan,
etc.). If do, you can get harm.
(3) When you move the printer.
This printer weighs 1 1.2kg including toner cartridge and cassette. Use safe lifting and handling techniques.
Back injury could be caused if you do not lift carefully .
(4) Ensure the printer is installed safely.
The printer weighs 1 1.2Kg, ensure the printer is installed on a level surface, capable of supporting its weight.
Failure to do so could cause the printer to tip or fall possibly causing personal injury or damaging the printer.
(5) Do not install the printer on a sloping or unstable surface. After installation, double check that the printer is stable.
Precautions
Samsung Electronics
Service Manual
1-5
1.3 ESD Precautions
Certain semiconductor devices can be easily damaged by static electricity. Such components are commonly called
“Electrostatically Sensitive (ES) Devices”, or ESDs. Examples of typical ESDs are: integrated circuits, some field
effect transistors, and semiconductor “chip” components.
The techniques outlined below should be followed to help reduce the incidence of component damage caused by
static electricity.
Caution >>Be sure no power is applied to the chassis or circuit, and observe all other safety precautions.
1. Immediately before handling a semiconductor component or semiconductor-equipped assembly, drain off any
electrostatic charge on your body by touching a known earth ground. Alternatively, employ a commercially available wrist strap device, which should be removed for your personal safety reasons prior to applying power to the
unit under test.
2. After removing an electrical assembly equipped with ESDs, place the assembly on a conductive surface, such as
aluminum or copper foil, or conductive foam, to prevent electrostatic charge buildup in the vicinity of the assembly .
3. Use only a grounded tip soldering iron to solder or desolder ESDs.
4. Use only an “anti-static” solder removal device. Some solder removal devices not classified as “anti-static” can
generate electrical charges sufficient to damage ESDs.
5. Do not use Freon-propelled chemicals. When sprayed, these can generate electrical charges sufficient to damage ESDs.
6. Do not remove a replacement ESD from its protective packaging until immediately before installing it. Most
replacement ESDs are packaged with all leads shorted together by conductive foam, aluminum foil, or a comparable conductive material.
7. Immediately before removing the protective shorting material from the leads of a replacement ESD, touch the protective material to the chassis or circuit assembly into which the device will be installed.
8. Maintain continuous electrical contact between the ESD and the assembly into which it will be installed, until completely plugged or soldered into the circuit.
9. Minimize bodily motions when handling unpackaged replacement ESDs. Normal motions, such as the brushing
together of clothing fabric and lifting one’s foot from a carpeted floor , can generate static electricity sufficient to
damage an ESD.
1. Exercise caution when replacing a super capacitor
or Lithium battery. There could be a danger of
explosion and subsequent operator injury and/or
equipment damage if incorrectly installed.
2. Be sure to replace the battery with the same or
equivalent type recommended by the manufacturer.
3. Super capacitor or Lithium batteries contain toxic
substances and should not be opened, crushed, or
burned for disposal.
4. Dispose of used batteries according to the
manufacture’s instructions.
1.4 Super Capacitor or Lithium Battery Precautions
Product specification and feature
Service Manual
2-1
Samsung Electronics
2
2
2. Product specification and feature
2.1 Product Specifications
2.1.1 Product Overview
Item Descriptions Remark
Basic Model SCX-4725FN(4-in-1 Flatbed MFP)
SCX-4725F(4-in-1 Flatbed MFP)
Target User SOHO, Economical(Speed/Price) Customer
Customer Benefits - Compact Size
(Sales Points) - 24ppm/A4, 24ppm/Letter fastest speed in its price class
- Favorite Copy
- ID Card Copy
- Toner Save
- up to 24ppm/A4(Up to 24ppm/Letter)
- 250 sheets Multi-Purpose type paper input/100 sheets Paper Output
- 3,000pages toner capacity
- 600dpi Print/Copy Resoulusion
- Samsung Print Language
- 32MB System memory
- 30 ADF
- 33.6 Kbps Fax Modem
- 100 Speed Dial
- 72 Hour Battery Back-up
Service Manual
Product specification and feature
2-2
Samsung Electronics
2.1.2 Specitications
Product Specifications are subject to change without notice. See below for product specifications
2.1.2.1 General Specitications
Item Descriptions (SCX-4725FN / SCX-4725F)
Major Features
Copier, Print, Scan, Fax(SCX-4725FN)
Net Dimension (WxDxH)
438(W)*374(D)*368(H)(17.2x14.7x14.5")
Net Weight (Inc. Toner Cartridge)
11.2kg
CPU Chorus-M (300MHz)
LCD 2 Line x 16 characters / 2Line x 8 characters(for china and korea)
Toner Save Yes (With toner save button)
I/O Interface USB2.0
Network Interface Yes
OS Compatibility Windows 98/Me/NT4.0/2000/XP, Various Linux OS (via USB interface only) including
Red Hat 8.0~9.0, Fedora core 1~3, Mandrake 9.0~10.2, and SuSe 8.2~9.2, Mac 10.3
Power Requirement
110 ~ 127 VAC, 50/60 Hz, 5.5A
220 ~ 240 VAC, 50/60 Hz, 3A
Power Consumption
Sleep Mode : Under 12W
Standby Mode : 70W
Average : 400W (Print Mode)
Energy Star Compliant Yes
Power Switch
Yes
Noise Warm up 49 dBA
Stand by 35 dBA
Coping 55 dBA
Printing 53dBA
Warm up time from Power On Status Less than 30 seconds
from Sleep Mode Less than 30 seconds
(Recovery time)
Max. Monthly
Print 10,000 pages
Volume
Scan ADF: 2,500 pages, PLATEN: 1,700 pages
Average Monthly Print Volume
700 pages
Average Monthly Scan Volume
150 pages
Machine Life
ENGINE 5 years or 50,000 Pages. Whichever comes first
SCANNER ADF : 30,000 Pages, Platen : 20,000 Pages
Operation Temperature
10°C ~ 32 °C (50°F ~ 89°F)
conditions
Humidity
20 % ~ 80 % RH
Approval Class B
Device Memory 32MB
Page Counter Yes
Print Configuration Sheet(System Data) Yes
Product specification and feature
Service Manual
2-3
Samsung Electronics
2.1.2.2 Print Specifications
2.1.2.3 Scan Specifications
Item Descriptions (SCX-4725FN / SCX-4725F)
Method
Laser Beam Printing
Speed
Up to
24ppm
in A4 (
24ppm
in Letter)
Emulation PCL
Power Save Yes
(Interval option: 5, 10,15, 30, 45 minute)
Resolution
Normal 1200 x 1200 dpi
RET -
Memory 32MB
First Print Out From Stand by Approx. 10 seconds
Time From Cold Status Less than 30 seconds
Duplex Print Manual
WHQL Compliant Window XP
Printable Area
A4: 201.6x288.6mm
LTR: 207.6x270.6mm
Legal: 207.6x347.6mm
Folio: 207.6x322.6mm
Halftone (Gray Scale) 256 levels
Item Descriptions (SCX-4725FN / SCX-4725F)
Compatibility
Twain standard / WIA Standard (Window 2000/XP)
Scan Method
600dpi Color CIS(Contact Image Sensor) Module
PC Scan Speed Lineart, Halftone 10sec Platen(13sec ADF)
through Platen Gray 23sec Platen (26sec ADF)
Color 300dpi 65sec Platen(70sec ADF)
Resolution Optical 600 x 600 dpi
Enhanced 4800 x 4800 dpi
Halftone 256 levels
Scan Size Max. Document Width Max.216mm (8.5")
Effective Scan Length 297 mm (11.7")
Effective Scan Width Letter/Legal: 208mm(8.2")A4: 202mm
Scan-to Button Yes
Application Yes
Scan Depth Color 24 bit
Mono 1bit for Line art, Halftone, 8 Bit for Gray scale
Service Manual
Product specification and feature
2-4
Samsung Electronics
2.1.2.4 Copy Specifications
Item Descriptions (SCX-4725FN / SCX-4725F)
Copy Speed
Up to 22ppm in A4 (22ppm in Letter)
Resolution
Optical 600*600 dpi (Scan:600*600dpi, Print: 600*600dpi)
- Text & Text/Photo mode : 600*300dpi(ADF, Platen)
- Photo mode : 600*600dpi (Platen), 600*300dpi(ADF)
Enhanced -
First Copy Stand by Approx. 16 seconds(ADF), Approx. 11 seconds(Platen)
Out Time From Power Save Mode Approx. 46 seconds(ADF), Approx. 40 seconds(Platen)
(110V only)
Original Image type selection Text, Text/Photo, Photo
Zoom Range 25-400%(Platen), 25-100%(ADF)
Multi Copy 1~99 Pages
Preset [Original(100%)], [A4
A5(71%)], [LGL LTR(78%)], [LGL A4(83%)],
[A4 LTR(94%)], [EXE LTR(104%)], [A5 A4(141%)], 25%, 50%, 150%
200%, 400%, [Custom: 25-400%)]
Darkness Control 3 level (Light, Normal, Dark)
Auto return to default mode Yes (after 1 minute)- Time out option: 15, 30, 60, 180 sec., Off
Changeable Default mode Darkness, Original Type, Reduce/Enlarge, No. of Copies
ID Card Copy 2-up Yes (ADF Only)
4-up Yes (ADF Only)
Collation Yes (ADF Only)
Autofit Yes (Platen Only)
LD Card Copy Yes (Platen Only)
Clone Yes (Platen Only)
Poster Yes (Platen Only)
Product specification and feature
Service Manual
2-5
Samsung Electronics
2.1.2.5 Telephone Specifications
Item SCX-4725FN
Handset No
On hook Dial Yes
Search Yes(Phone Book)
1-Touch Dial 10 ea (0~9)
Speed dial 90 locations(10~99)
TAD I/F Yes
Tone/Pulse Tone
Default, Pulse Changing in Tech Mode
Pause Yes
Auto Redial Yes
Last Number Redial Yes
Distinctive Ring Yes
Caller ID No
Extention Phone Interface Yes
Report & List Tx/Rx Journal Yes
Print out Confirmation Yes
Help List No
Auto Dial List Yes
System Data List all user setting
Sound Control Ring Volume Yes(Off,Low,MED,HIGH)
Key Volume Yes(On,Off)
Alarm Volume Yes(On,Off)
Speaker Yes(On,Off, Comm)
Service Manual
Product specification and feature
2-6
Samsung Electronics
2.1.2.6 Fax Specifications
Item SCX-4725FN
Compatibility ITU-T G3
Modem Speed 33.6Kbps
TX Speed 3sec
Compression MH/MR/MMR/JBIG
Color Fax Yes(Tx Only)
ECM Yes
Resolution Std 203x98dpi
Fine 203x196dpi
S.Fine 300x300dpi
Photo 203x196dpi
Color 200x200dpi
Auto Switching Yes
Scan Speed Standard approx. 3sec (ADF)
approx. 5sec (Platen)
Fine approx. 7sec (ADF)
approx. 8sec (Platen)
S.Fine approx. 7sec (ADF)
approx. 8sec (Platen)
Rx fax duplex print out No
Multiple page scan speed 7 cpm / Ltr (Standard Resoution Res.)
(Memory Tx.)
Receive Mode Fax, TEL, Ans/Fax, DRPD
Memory Capacity 2MB (When Power off Memory Back up)
Optional Memory No
Max locations to store 99 locations
to 1 Group Dial
Fax Forward Yes(On/Off)
Broadcasting 109 locations(Max locations)
Cover page NO
Delayed fax Yes
Memory RX Yes
Functions Voice Request No
TTI Yes
RTI Yes
Polling No
Earth/Recall No
Auto Reduction Yes
RDS Yes
Junk Fax barrier Yes
Security Receive Yes
Memory Back-up Max. 72hours
Product specification and feature
Service Manual
2-7
Samsung Electronics
2.1.2.7 Paper Handling Specifications
2.1.2.8 Software Specifications
Item SCX-4725FN / SCX-4725F
Input Capacity and Types 250-sheet Cassette Tray (75 g/ , 20 lbs)
Output Capacity and Types 100-sheet Face Down(75 g/ , 20 lbs)
Manual Tray 1 sheet
Media size
A4, A5, A6, Letter, Legal, Folio, Executive, ISO B5, JIS B5, Monarch, Envelope, No.10, DL, C5, C6
76 x 127 mm (3" x 5") ~ 216 x 356 mm (8.5" x 14")
Media Type
Plain Paper, Transparency, Label, Envelope, Tick, Thin, Bond, Color Paper, Card Stock, Preprinted
Paper Weight 16~24lb (60 to 90g/ ), Cassette Tray
16~43lb (60 to 165g/ ) for 1 sheet, Manual Tray
ADF Capacity Up to 30 sheets of 20lb(75g/ ) paper
ADF Document Size Up to Legal
Item SCX-4725FN / SCX-4725F
Compatibility DOS No
Win 3.x No
Win 95 No
Win 98/ME Yes
Win NT 4.0 No
Win 2000 Yes
Win XP Yes
Mac Yes (10.3 )
Linux Yes
Driver Printer PCL
TWAIN Yes
WIA Yes
ScanToPC Yes
PC-FAX Yes (Send only)
Application RCP Yes
Status monitor Yes
SmarThru4 Yes
Service Manual
Product specification and feature
2-8
Samsung Electronics
2.1.2.9 Accessory
2.1.2.10 Consumables
Item SCX-4725FN SCX-4725F
Quick Setup Guide Yes (include Setup Guide and Function Guide)
Quick User Guide Yes (Korea Only)
S/W CD ROM
3 CD (Contents; Electronic User Manual, SmarThru, Print Driver, Twain Driver, RCP)
Toner Cartridge 1 EA
Power Cable 1 EA
Telephone Jack No 1 EA
Printer Cable No No
Tray Coner Yes Yes
Item SCX-4725FN / SCX-4725F
Type Single Cartridge
Front door open and front loading
Toner Yield
3,000 pages at ISO 19752 Std. Coverage(Ships with 1,000 pages Starter Toner Cartridge)
Code SCX-4525D3
Level Sensor -
Product specification and feature
Service Manual
2-9
Samsung Electronics
2.1.3 Model Comparison Table
2K
Single Cartridge
USB 2.0,
Ethernet 10/100 Base TX
497 x 406 x 393 mm
50 sheets
250 -sheet MP Tray
119 Locations
2 MB (Up to 110 pages)
33.6 Kbps
Up to 600 dpi
600 x 600 dpi
18 ppm/A4 (19ppm/Ltr)
PCL6, PS3
Up to 1200 x 1200 dpi
18 ppm/A4 (19ppm/Ltr)
(Starter 1,5K/ 12K)
Toner 2,5K/ Drum 12K
2-piecese Cartridge
USB 1.1, IEEE 1284,
Ethernet 10/100 Base TX
432 x 395 x 294 mm
35 sheets
250 - sheet CST Tray
208 Locations
Approx. 600 pages
33.6 Kbps
600 x 2400 dpi
600 x 300 dpi
20 ppm/A4 (20ppm/Ltr)
PCL6, PS3
2400 x 600 dpi
20 ppm/A4 (20ppm/Ltr)
1200 x 2400 dpi600 x 2400 dpi Resolution (Optical)Scan
2.5 K
Single Cartridge
USB 2.0,
Ethernet 10/100 Base TX
486 x 477 x 442mm
50 sheets
250 - sheet CST Tray
Speed 12 / Coded 100
Approx. 256 pages
33.6 Kbps
600 x 600 dpi
20 ppm/A4 (21ppm/Ltr)
GDI
1200 x 600 dpi quality
20 ppm/A4 (21ppm/Ltr)
Single Cartridge Type
3 K (Starter 1.5K)Yield
Cons.
USB 2.0,
Ethernet 10/100 Base TX
Interface
438 x 374 x 368mm (TBD)Net Dimension
General
30 sheetsADF Capacity
250 - sheet MP TrayInput Capacity
Paper
1-touch 10 / Speed 190Auto Dial
Approx. 320 pages Memory
33.6 KbpsModem Speed
Fax
600 x 600 dpiResolution
24 ppm/A4 (25ppm/Ltr)Speed
Copy
PCL6, PS3Emulation
1200 x 1200 dpiResolution
24 ppm/A4 (25ppm/Ltr)Speed
Model Image
Item
Print
-
HP LJ 3055
(
Brother MFC 7820N Canon MF 5770
K
SCX - 4725FN
(Whitney-2 24ppm)
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Samsung Electronics
2.2 System Overview
2.2.1 System Layout
The SCX-4725FN/4725F is roughly made up Main Control part, Operation Panel part, Scanner part, Line
Interface part and Power part. Each Part is separated Module which focus on common and standard design
of different kind products. main control part adopting Fax & LBP Printer exclusive Controller is chorus-M
CPU(ASIC) and 1 Board. Scanner part is composed of ADF and Platen and is connected with Main by
Harness.
Product specification and feature
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Samsung Electronics
2.2.1.1 Feeding section
There is a universal cassette which automatically loads paper and the manual feed which supplies paper
single sheet at a time. The cassette has a friction pad which separates paper to ensure single sheet
feeding, and it has a sensor, which checks when the paper tray is empty.
- Feeding Method: MP Cassette Type
- Feeding Standard: Center Loading
- Feeding Capacity: Cassette-150 sheets (75g/m2, 20lb paper standard)
Manual 1 sheet (Paper, OHP, Envelop, etc.)
- Paper detecting sensor: Photo sensor
- Paper size sensor: None
2.2.1.2 Transfer Ass’y
This consists of the PTL (pre-transfer lamp) and the Transfer Roller. The PTL shines a light onto the OPC
drum. This lowers the charge on the drum’s surface and improves transfer efficiency.
The transfer roller transfers toner from the OPC drum surface to the paper.
- Life expectancy: Over 50,000 sheets (at 16~30°C)
2.2.1.3 Driver Ass’y
- Gear driven power unit. The motor supplies power to the paper feed unit, the fuser unit, and the toner
cartridge.
2.2.1.4 Fixing Part(Fuser)
- The fuser consists of the Heat Lamp, Heat Roller, Pressure Roller, Thermistor, and Thermostat. It fixes
toner to the paper using pressure and heat to complete the printing job.
2.2.1.4(a) Temperature-Intercepting Device (Thermostat)
The thermostat is a temperature sensing device, which cuts off the power to the heat lamp to prevent
overheating fire when the heat lamp or heat roller overheats.
2.2.1.4(b) Temperature Detecting Sensor (Thermistor)
The Thermistor detects the surface temperature of the heat roller, this information is sent to the main
processor which uses this information to regulate the temperature of the heat roller.
2.2.1.4(c) Heat Roller
The surface of the Heat Roller is heated by the Heat Lamp. As the paper passes between the Heat and
Pressure rollers the toner is melted and fixed permanently to the paper. The surface of the roller is coated
with Teflon. This ensures that toner does not adhere to the roller surface.
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Samsung Electronics
2.2.1.4(d) Pressure roller
The Pressure Roller mounted under the heat roller, it is made of a silicon resin, and the surface of the roller
is coated with Teflon. This ensures that toner does not adhere to the roller surface.
2.2.1.4(e) Safety Features
• To prevent overheating
- 1st protection device: Hardware cuts off when overheated
- 2nd protection device: Software cuts off when overheated
- 3rd protection device: Thermostat cuts off mains power to the lamp.
• Safety device
- Fuser power is cut off when the front cover is opened
- LSU power is cut off when the front cover is opened
- The temperature of the fuser cover's surface is maintained at less than 80°C to protect the user and a
caution label is attached where the customer can see it easily when the rear cover is opened.
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Samsung Electronics
STACKER
COVER-M-SIDE R
EXTEND-SMALL
EXTEND-LARGE
TRAY CASSETTE
COVER-M_DEVE
FIXING BKT
SPEKER
COVER-M-SIDE-L
COVER-M_REAR
COVER-M_JAM
COVER-M_MIDDLE
SCAN
UPPER
MOTOR
ASS'Y
SCAN
LOWER
TIMING
BELT
CIS
SLIDER
-CIS
ADF
GLASS
SCAN
GLASS
KEY & OPE
COVER
[Case part figure]
[Scan part figure]
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Samsung Electronics
2.2.2 Engine H/W Specification
1) Recording Method : LSU(Laser Scanning Unit)
2) Printing Speed : 24ppm
(In continuing printing base Letter, printing pages from 2nd to last during 1min)
3) Recording Density : 1200 dpi
4) Cassette Capa. : Cassette ; 250sheets(75g/ Base), 1-sheet Feeding : N/A((DRIVE Selection : Paper, OHP,
Envelop - 1 sheet)
5) Manual Tray : All paper 1 sheet
6) Paper Size : Cassette ,Manual ; Width = 76 ~ 216mm, Length = 125mm ~ 356mm
7) Effective recording size
- A4 :202 x 291 mm
- Letter : 208 x273mm
- Legal : 208 x 350 mm
- Folio : 208 x 325 mm
- TopMargin: 2 2 mm
- Left, Right Margin : 2 2 mm
8) CRU(Toner Cartridge)Life : 3,000pages Printing(A4, ISO Standard Pattern Printing)
9) First Print Out Time : within 11sec ( Standby )
10) Warming up time : within 35sec (Ambient : 25 °C)
2.2.2.1 Main Board Control Part
Main control part of SCX-4725FN is made of ASIC(CPU, Image processor, PC I/F part include, Scan interface part,
FAX Modem part and Printing process I/F part. CPU handles the BUS control, I/O interface, scan interface, PC
interface and other miscellaneous driver circuit.
1) Main Board
- Main Board has a function of sending Current Image Video Data to LSU of the machine, controlling motor
Driving Circuit and monitoring Paper Exit Sensor, Cover Open switch, OPE Panel Inputs.
2) Main Controller
- CPU : Chorus-M is the main CPU and is made up on the 32bit RISC architecture using ARM 920T core.
Main CPU controls the whole system according to the program code which stored in the FlashROM memory.
- Operation Frequency : CPU Core -> over 300MHz, System Bus -> 100MHz
- Summary of the Key Function Block:
1.3V for internal Core, 3.3V for I/O Pad with 16KB I-Cache and 16KB D-Cache.
Image Processor included.
On-Chip clock generator with PLL.
Memory and External Bank Control.
DMA Control (16-Channel)
Interrupt Control.
2-port USB Host/1-port USB device(ver 1.1) interface control.
Parallel interface control.
UART(1-Channel)
Product specification and feature
Service Manual
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Samsung Electronics
Synchronous Serial Interface Control.
A/D Converter(10-bit, 8channel).
General I/O Port control.
RTC with calendar function.
S/W Assistant function(Rotator)
- Flash Memory : Stores system program and can be updated to the newer system program code through
the PC interface. It stores the FAX Journal List, One Touch dial number, speed dial number, and machine
configuration setup data.
Capcity : 16 Mbyte (NOR Type)
Access Time : 70 nsec
- SDRAM : SDRAM is used for Print Buffer, Scan buffer when scanning, ECM Buffer when FAX Receiving,
and system working memory.
Capacity : 32 Mbyte
Access Time : 166MHz(Max)
Data Backup : 48 Hours
Backup Battery Charging Time : 100hours when completely discharged.
2.2.2.2 Scan Part
1) Image Signal Input Part
- Image Signal from CIS has a level of about 1.2V and is goes to ADC of Chorus2.
After ADC, CIS analog signal will be converted to 8-bit Digital signal.
2) Image Processing
- On the surface of the original paper, the light from the CIS LED reflected and goes to the CIS Sensor.
Then the light is converted to the appropriate voltage suitable for ADC input. Analog signal from CIS
sensor is used for ADC input then is converted to 8-bit digital data. Image processor of the Chorus2 will
do the Shading correction function at first, then Gamma correction function next. After then, the data goes
to different module according to the copy or FAX resolution mode. When Text mode, the image data
goes to LAT module, when Photo mode, the image data goes to Error Diffusion module, when PC-Scan
mode, the image data goes directly to the PC through DMA access.
Summary of the Image sensor interface is as below;
- Minimum Scan Line Time :1.5ms
- Scan Resolution : 600*600 dpi
- Scan Width : 208mm
- Function
White Shading Correction
Gamma Correction
CIS Interface
256 Gray Scale
3) CIS Driving Part
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Samsung Electronics
- CIS Supply Voltage : +3.3V
- CIS Max frequency : 5MHz
- CISLinetime
Fax/Copy - 1.5ms
PC-Scan - 4.5ms
- White output volt. : Max 0.8V
4) ADF Driving Part : Driving ADF Stepper motor, and the maximum motor speed is 2000PPS.
- MOTOR DRIVER : A3978(Allegro)
- Driving Voltage : 24V DC
- Phase : 2-2 Phase 2000PPS at Quick Scan,
2-2 Phase 1000PPS AT Fine Scan,
2-2 Phase 667PPS AT Super Fine Scan
2.2.2.3 FAX Section
Modem Part
BLOCK DIAGRAM
Implemented by based on Conexant DAA (Data Access Arrangement) Solution, and is roughly composed of two kinds
Chip Solution
- CX86710 (SFX336): Existing Modem Chip which adds SSD (System Side Device) for interfacing between LSD and DIB
of FM336Plus Core
- CX20493 (LSD) : LIU (Line Interface Unit) Chip which is controlled by SSD and satisfies each PSTN Requirements by
modulating internal Configuration with connecting Tel Line.
Product specification and feature
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Samsung Electronics
Modem (SFX336) specification.
2-wire half-duplex fax modem modes with send and receive data rates up to 33,600 bps
V.17, V.34, V.29, V.27 ter, and V.21 Channel 2
Short train option in V.17 and V.27 ter
PSTN session starting
V.8 and V.8bis signaling
HDLC support at all speeds
Flag generation, 0-bit stuffing, ITU CRC-16 or CRC-32 calculation and generation
Flag detection, 0-bit deletion, ITU CRC-16 or CRC-32 check sum error detection
FSK flag pattern detection during high-speed receiving
Tone modes and features
Programmable single or dual tone generation
DTMF receiver
Tone detection with three programmable tone detectors
Receive dynamic range:
0 dBm to -43 dBm for V.17, V.29, V.27 ter and V.21 Channel 2
9dBm to -43 dBm for V.34 half-duplex
Digital speaker output to monitor received signal
Two16-byte FIFO data buffers for burst data transfer with extension up to 255 bytes
V.21 Channel 1Flag detect
V.21 Channel 1Flag detect
+3.3V only operation
Typical power consumption
Normal mode: 264 mW
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Samsung Electronics
Signal Transition of DAA Solution
Line Interface Signal of Tel Line and LSD is Analog Signal.
2) there is A/D, D/A Converter in LSD, so Analog Signal from Tel Line is converted in Digital through A/D Converter in
DAA and transfer to SSD by DIB Capacitor
Digital Signal from SSD is converted to Analog by D/A Converter in DAA and transfer to Tel Line
Transformer transfer Clock from SSD to LSD and Clock Frequency is 4.032MHz.
LSD full wave rectifies Clock to use as inner Power supply and also use as Main Clock for DIB Protocol Sync between
LSD and SSD. Transformer transfer Clock by separating Primary and Secondary, and
amplifies Clock Level to LSD by Coil Turns Ratio 1:1.16.
Clock
- Clock is supplied by transformer from SSD to LSD, and there is PWROUT to adjust output impedance of Clock
Out Driver is inside SSD and CLKSHIGH Resistor to adjust duty of HLPWR Resistor and Clock.
Clock from SSD to LSD has Differential structure of 180 phase difference for Noise Robustness
DIB Data transfer Data from SSD to LSD by Transformer, and also transfer specific data from LSD to SSD.
After transferring data from SSD, RSP is transferred and LSD recognizes RSP and change LSD to output Driver transfer
Data to SSD.
DIB Data form SSD to LSD by Transformer has Differential structure of 180 phase difference between DIBP and DIBN for
Noise Robustness
SSD
CLKP
CLKN
LSD
DIBP
DIBN
Product specification and feature
Service Manual
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Samsung Electronics
2.2.2.4 Line Interface Part
This is Connection Part between system and PSTN(Public Switched Telephone Network), and primary circuit is usually
located. Main functions are Line Interface, Telephone Connection and Line Condition Monitoring.
1 Telephone Line Connection
Modular Plug : RJ-11C
LIU PBA Modular Type : 623 PCB4-4
Line Code Length : 2500 50mm
Line Code Color : Black
ON HOOK state Characteristic
1) DC Resistance
DP Dial Mode (Direct Current 30mA) : 50 ~ 300ohm
DTMF Dial Mode (Direct Current 20mA) : 50 ~ 540ohm
2) Ring Sensitivity
Ring detection Voltage : 40Vrms 150Vrms (condition :Current=25mA,Frequency=15Hz)
product Margin : 30Vrms 150Vrms
Ring detection Frequency : 15.3Hz 68Hz (condition : Voltage=45Vrms,Current=25mA )
product Margin : 15Hz 70Hz
Ring detection Current : 20mA 100mA (condition : Voltage=40Vrms,Frequency=20Hz)
product Margin : over 15mA
3) False Ring Sound
Ring Frequency : 750 Hz + 1020 Hz
Ring interrupt Cycle : On/Off depending on input Ring Signal Cycle.
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Samsung Electronics
2.2.2.5 Printing Part
Printing Process part is made of PC-Interface part, PVC(Priter Video Controller), LSU control part, High Voltage
control part and Fuser Unit control part. PC-interface core is included in the Chorus2 ASIC and controls the PCinterface. LSU control part controls the LSU polygon motor, Laser diode, video data output so thatthe printing image
can be made up on the OPC Drum.
2.2.2.6 Engine Paper Feeding
1) Feeding Type : MP Cassette Type
2) Feeding Standard : Center Loading
3) Feeding Qty : Cassette 150 sheets (75g/ , 20lb paper standard)
4) 1 sheet (Paper, OHP, Envelope etc.)
5) Separating Type: Cassette - Friction Pad Type
6) Manual Tray : 1 sheet
7) Driver Type : Driving by Gearing from Main Motor
8) Pick_up Roller Driver : Solenoid
9) Pick up Roller Rubber Material : EPDM+IR =1.3 or more
10) Pick up Velocity : 94.8731mm/Sec (Process : 93.0667mm/sec)
11) Paper detecting Sensor : Photo Sensor
12) Paper Size Sensor : None
13) Paper Separating Pad Material : NBB 52 °, =0.8~1.2
14) Separating Pad Pressure : TBD 150 gf
15) Pick_up Roller RPM : 47.683 RPM
16) Feeding Pressure (Same as Transfer Roller)
17) Paper Exit Type : Face Down
18) Feed Roller Force : TBD Kg.f or more.
19) Spring Feed Tensile Force : TBD gf
20) Feed roller Velocity : mm/sec
21) Feed Roller Material
22) Exit Sensor : Photo Sensor
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