Brother mfc8440 - 1.3.10 Engine I;O; 1.3.11 Panel I;O; Eeprom; Reset Circuit

MFC-8440/8840D/8840DN, DCP-8040/8045D/8045DN
SERVICE MANUAL
3-7
1.3.8 EEPROM
The EEPROM is BR24126 type of two-wire method with a 8192 x 8bit configuration.
Aurora
U15
Fig. 3-10
1.3.9 Reset circuit
The reset IC is a R3112N281C. The reset voltage is 2.8V (typ.) and the LOW period of reset is
22.4ms (typ.)
R84
68
C77
C101
0V
TP4
U5
R3112N281C
5
CD
2
VCC
1
VOUT
4
NC
3
GND
C75
C103
0V
VDD3
C71
C103
TP310
Fig. 3-11
1.3.10 Engine I/O
The interface with the engine PCB is by full-duplex synchronous serial method, of which
transfer rate is 520kbps.
3D
ENGDI
1D
ENGDI
ENGDI
U7
Aurora
254
ENGRSTN
253
ENGDO
255
R139
4.7k
VDD5
VDD3
R140
4.7k
L11
0
VDD3
0V
C143
C102
R141
100
C152
C103
C154
C103
C153
C101
C142
C101
L10
0
L15
0
L14
0
L12
0
L13
0
R142
1k
R138
100
TP202
TP203
TP200
TP201
TP204
TP205
CN9
1
3.3V
B6B-PH-K-S
2
0V
3
TXD
4
RXD
5
RESET
6
5V
ENGINE
Fig. 3-12
1.3.11 Panel I/O
The interface with the panel PCB is by full-duplex synchronous serial method.
Fig. 3-13