Service manual

5-24 Samsung Electronics
5-1-6 MOTOR DRIVER
5-1-6-1. GENERAL
SMARTJET use 2 stepper motors, i.e. CR(Cartridge Return) motor and LF(Line Feed) motor.
CR motor moves left and right all-in-one carriage of inkjet head and shuttle scanner. It helps the printer print
accurately on the paper and the scanner read image data accurately. LF motor is driven to feed and eject
paper for printing and to feed and eject documents to read for scanning. Bi-polar CR motor is controlled half
step with maximum 24ips(inch/sec), while LF motor half step and quarter step at maximum 6ips.
5-1-6-2. CR(CARRIAGE RETURN) MOTOR DRIVING CIRCUIT
CR motor moves the carriage left and right when ink cartridge prints something on paper or shuttle scanner
reads image data.
- Motor Type : Stepper motor, bi-polar
- Driving Voltage : +30V
- Winding Resistance : 6½ ± 10%
- Driving IC : TEA3718DP X 2
CR_REF
CRIA1 CRIA0
CURRENT(mA) OPERATION REMARK
(CRIB1) (CRIB0)
H L L 490 Mono LQ is being driven
L L L 670 Color draft is being driven
L L L 670 Mono draft is being driven
X H H 0 No current
As shown in the above table, current in each mode is adjusted by voltage of driver(U25, U26) CRVREF input.
If the output of CR_REF signal controlled by MFP controller(U15) is ÒlowÓ, TR(Q12) will be turned off and the
voltage put in to CRVREF of driver (U25, U26) with +5V divided will go up (+4.5V). It becomes the standard
of the driver, resulting in high current. If CR_REF output is ÒhighÓ, TR(Q12) will be turned on and the volt-
age put in to CRVREF will go down (+3.0V), resulting in low current in the motor.