Samsung SF3000 Service Manual

Also see for SF3000: Operator's guide

Contents

5-4 Samsung ElectronicsCircuit Description5-2-7. ResetTo initialize the chip’s internal logic, the reset input(/RESET) must be held to 0 Volt for at least 22 CPUclocks. During this time, Vdd must be greater than 3volt. The watchdog timer can also invoke a systemreset.[+5V Power Monitoring]If 5 Volt power to KIA7045P drops to between 4.65Vand 4.35V (typically 4.5V), power failure will beindicated and the output of KIA7045P will go ‘low’(GND5). This causes the KS16118 to become active(‘low’=reset).The KS32C6500 reset causes the /RESET terminal tobe reset. The output terminal of KIA7045P is anopen-drain configuration, and is connected toKS32C6500 through a 10 kohm pull-up resistor.5-2-8. Carriage Return Motor DriverThe CR motor drives the head in two directions toprint data on the recording paper.Motor type : Step BipolarOperation Voltage : +24V DCResistance : 5 ohm +/-10%IC : PBL3717 x2EASTEP MOTOR DRIVER OUTPUT SIGNAL5-2-9. Line Feed Motor DriverThe LF motor feeds paper in and out.Motor type : Step UnipolarOperation Voltage : +24V DCHolding Voltage : +5V DCResistance : 50 ohm ±10%IC : STA471A5-2-10. Head Nozzle DriverThe nozzle control circuit is composed as follows:Number of nozzle : 56 nozzles for monoDriving Voltage : +24V DC +/-2%Driving Pulse Width : 3.6 us for monoOperation Frequency : 5 kHzResistance : 30 ohm for monoIC : SGS Thomson L6451 or Allegro A5817The IC decodes four input signals (PHINA, PHINB,PHINC, PHIND) and enables the selected usingOEA and OEB signal input.IND INC INB INA N0 0 0 0 00 0 0 1 10 0 1 0 20 0 1 1 30 1 0 0 40 1 0 1 50 1 1 0 60 1 1 1 71 0 0 0 81 0 0 1 91 0 1 0 101 0 1 1 111 1 0 0 121 1 0 1 131 1 1 0 ALL OFF1 1 1 1 ALL OFFTable 5-1 Nozzle Driver SignalFigure 5-5 Step Motor DriveCRIAOStandby Full StepCRIA 1PHAPHBCRIBOINPUTOUTPUTCRIB 1500mAIMA-500mA-500mA500mAIMB