Samsung SF5800 Alignment and Adjustments

5-26 Samsung Electronics

Circuit Description

5-3 OPE PBA

5-3-1 SUMMARY

OPE Board i s separated functionally from the main
board and operated by the micom(Z8601) in the
board. OPE and the main use UART (universal
asynchronous receiver/transmitter) channel to
exchange information. OPE reset can be controlled by
the main. OPE micom controls key-scanning and LCD
and LED display, detects documents and
senses SCAN position. If there occurs an event in OPE
(such as key touch and sensor level change), it sends
specific codes to the main to respond to the situation
and the main analyzes these codes and operates the
system. For example, if the main is to display
messages in OPE, the main transmits data through
U A RT line to OPE according to the
designated format and OPE displays this on LCD,
LED. OPE’s sensing is also transmitted to the main
through UART line and then the main drives
necessary operation.

5-3-2

OPE PBA consists of U1 (MICOM, Z8601), LCD, key
matrix, LED indicators, SCAN position sensor and the
document detect sensor. Refer to OPE Schematic
Diagram and Wiring Diagram sections of this manual.

• Signals fr om the key matrix are deliver ed to U1X/Y
input pin group (P1-x).

• U1 pin 4 (TX D ATA) is the UART code sent to
MAIN PBA.

• Display from the contro ller is r eceived at U1 pin 5
(RX DAT A).

• LCD drive signals are sent fr om U1 P2-x pin group,
P3-4~P3-6 pins.

• Machine status LED drive signals are sent fr o m U 1
P0-x pin group.

• Document detect sensor output is received at U1
pin 33 (P3-3).

• Scan position sensor output is r eceived at U1 pin 43
(P3-1).

OPE BLOCK DIAGRAM

Samsung Electronics 5-27

5-4 LIU PBA

5-4-1 Summary

LIU(Line Interface Unit) circuit added only to
Msys 5200, Msys 5150, SF-5800, SF-5800P is
controlled by the main cir c uit.
It monitors telephone line and helps interface between
the system and the telephone line. It uses
1-LIU(STI9510) to control the whole LIU,
MODEM/LINE INTERFACE, RING SIGNAL
DETECTOR, DIALER, LINE CURRENT
DETECTOR, and SERIAL INTERFACE.

5-4-2 Modem/Line Interface

This is the path thr ough which transmitted and
received data of modem is put in and out.

• CML1 Relay: It divides telephone line into
external telephone and fax.

• U3-3 TIT(Transformer Input from Transformer):
This single ended input receives image signals fro m
modem through transformer T2 and
transmits them on telephone line.

• U3-40 ROT(Receive Output Transformer): This
output transformer receives signals on telephone
line and delivers them to modem through
transformer T1. It has AC impedance of 10Kohm or
over.

• AC impedance: Normal operation range of
U3(STI9510) is fro m 15mA to 100mA. DC
characteristics depend on the voltage of U3-37
LI(Line Input) terminal and the voltage of
resistance R48 between U3-37 LI(Line Input)
terminal and U3-39 LS terminal.

5-4-3 Ring Signal Detector

• U3-28(MO) terminals are ring signal output
terminals. Q4 and Q5 put out ring signals and drive
Piezzo, but Msys 5200, Msys 5150, SF-5800,
SF-5800P does not use Piezzo. It has only the
functions related to ring detection such as driving
the photocoupler of U4 and delivering ring signals
to MFP
controller of the main.

5-4-4 Dialer

5-4-4-1. MF DIAL

• Default mode it is set in DP. Y ou can change it to
MF mode by contro l of MF P contr oller.

• MF signal can be measured a t (tone level of low
group: typical - 14dBm) U3-4 MFO(DTMF
Generator Output). The signal is adjustable by R40,
R41 and C29. The adjusted signal enters U3-9 MFI
(DTMF Amplifier Input) and is amplified to be
transmitted on telephone line.

• U3-39 LS(Line Current Sense Input) terminals show
the final signals transmitted to telephone line.

5-4-4-2. DP DIAL

• If U3-2(DMS) is made Vcc by R42, it is set at 33:67
D P signal. If it is made Vss by R43, it is set at DP
signal. This product is set at DP signal.

• D P signal is made by U3-27(DPn) terminals. This
signal turns on/off Q1. The signal made at that time
turns on/off Q2, which interrupts DC
current on telephone line and puts out pulse
signal on telephone line.

• U3-35 CS terminals : It makes Make Resistance by
shorting telephone line with Vss during Make
period of DP d ial.

5-4-5 Line Current Detector

• When CML1 relay connects telephone line, U3
(STI9510) of LIU board and MFP contr oller of the
main board (U16) start communication through
U A RT. U3 of LIU board sends signal that includes
information of line curr ent value, whenever it
receives orders or data fr om U16 of the main board.

Circuit Description

5-28 Samsung Electronics

Circuit Description

5-4-6 Serial Interface

• This part does serial communication with MFP
controller of the main boar d (MAIN PBA:U16) that
controls the whole system. It contr ols LIU by giving
and taking all control orders and line
status.

• U3-11 RxD : Schmitt Trigger input, Receiving
terminal.

• U3-29 TxD : Open Drain output terminal

• Standard U ART communication

- Baud Rate : 9600bps

- Start, Stop bit : 1bit each

- Data bits : 8 bit

- Parity bit : none

5-4-7 MAJOR FUNCTIONS OF PARTS

1) U3 : STI9510

- Key part of LIU board. Speech Network,
Dialer, Ringer and UART a re built in one IC
package.

2) U5 : PC817

- Photo coupler. It enables UART of
U3(STI9510) to receive contr ol signal or
dialing information fro m M F P contr oller of
the main board (U15).

- Insulation Detween prinary and secondany
cir cuit part.

3) U6 : PC817

- Photo coupler. It enables UART(U3-29:TxD)
of U3(STI9510) to deliver telephone line
status or r esponse signal about contro l
signal or dialing information fro m LIU MFP
controller of the main boar d (U15).

- Insulation Detween prinary and secondany
cir cuit part.

4) U4 : PC817

- It senses and delivers ring signal to the main
board.

- Insulation Detween prinary and secondany
cir cuit part.

5) U2 : PC814

- It senses hook-off (Line connection) of the
external telephone and delivers it to the main
board.

- Insulation Detween prinary and secondany
cir cuit part.

6) BD1 : BRIDGE DIODE

- Regardless of the polarity of DC power

fr om telephone line, the voltage put out on
Pin.1 has always + polarity against pin
Pin.2. So DC loop forms always in the same
dir ection r egardless of the polarity of the
telephone line.

7) T2,T3 : TRANSFORMER

- It delivers signals fr om the telephone line
to modem or signals from modem to the
telephone
line.

- Insulation Detween prinary and
secondany circuit part.