Control Board - Philips LX600 Service Manual

5-1

CONTROL BOARD

TABLE OF CONTENTS
IC Interbnal Block Diagram ............................................. 5-1
Circuit Diagram ................................................................ 5-2
PCB Layout Top & Bottom View ...................................... 5-3
Electrical Parts List .......................................................... 5-4
HT16511 INTERNAL BLOCK DIAGRAM
Command Decoder
DI
DO Serial I/F
Display RAM
CLK
20-Bit x 16 Words
CS
Timing Generator
OSC OSC
Key Scan
Key Data RAM
(4 x 12)
K0-K3
5-Bit Latch
4-Bit
SW0-SW3
Latch
LED0–LED4
HT48R05A INTERNAL BLOCK DIAGRAM
STACK0
STACK1
Program
Program
Counter
ROM
Instruction
M DATA
Registor
MP
U Memory
X
MUX
Instruction
Decoder
Status
ALU
Timing Shifter
Generator
ACC
OSC2
OSC2
RES
VDD
VSS
Voltages:
IC251 (HT16511)
PIN NO 1 2 3 4 5 6 7 8
Voltage 0 0 0 0 3.8 3.8 0 3.8
PIN NO 21 22 23 24 25 26 27 28
Voltage -21.8 -15.6 -13.4 - 20 -13.4 -20 -22.4 -18 -20.3 -13.2 -15.8 -11.4 -4.6 -22.6 -20.4 -20.4 -20.4 -20.4 -20.4 -20.4
PIN NO 41 42 43 44 45 46 47 48
Voltage -20.4 -20.4 -20.5 -20.4 4.6 4.6 4.6 4.6
IC252 (HT48R05A)
PIN NO 1 2 3 4 5 6 7 8
Voltage
5.1 5.1 5.1 0 5.1 0 5.1 0
Q201 (2SA812) Q202 (2SA1623)
PIN NO b c e PIN NO
Voltage 4.4 4.1 4.0 Voltage 4.9
5-1
12
20 12
20-Bit
S1/K1–
Segment
S12/K12
Output Latch
Driver
8
8
8
Multiplexed
S13/G16–
S20/G6
Driver
8
16 Bit
8
Shift Register
Grid
8
16
G1–G8
Driver
Diming Cirduit
VDD VSS VEE
INT/PC0
Interrupt
Circuit
M
Prescaiser
U
TMR
X TMR/PC1
INTC
TMRC
PC1
WDTS
M
fsus/4
WDT U
WDT Prescaiser
X
RC OSC
PCC
PORT C
PC0-PC1
PC
BZ/BZ
PBC
PORT B
PB0-PB2
PB
PAC
PORT A
PA0-PA7
PA
9 10 11 12 13 14 15 16 17 18
3.7 0 0 0 0 0 19.7 -22.2 -22.0 -11.2 -19.9 -17.8
29 30 31 32 33 34 35 36 37 38
49 50 51 52
0 4.6 0 0.9
9 10 11 12 13 14 15 16 17 18
0 4.9 4.9 5.2 0 0 0 0 0 0
b c e
0 4.8
fsys
19 20
39 40
19 20