Service Modes, Error Codes, and Fault Finding
EN 54
SDI PDP 2K7
5.
Figure 5-48 Defect overview 50” HD W2 [9/11]
H_16
8
70_059.ep
s
050407
Defect: V
s
ch volta
g
e ouput i
s
abnormal (50
”
only)
Y-MAIN Protection Check (50
”
only)
S
ymptom : The
ab
norm
a
l im
a
ge
a
ppe
a
r
s
in
s
ome
c
aus
e depending on
ab
norm
a
l V
s
ch volt
a
ge.
Y o
u
t in o
s
cillo
s
cope
<The
ab
norm
a
l Y o
u
t> <The norm
a
l Y o
u
t>
Check the V
s
ch volt
a
ge or repl
a
ce the Y-Bo
a
rd
Protection circ
u
it
- Volt
a
ge
S
en
s
ing : The import
a
nt volt
a
ge
s
en
s
ing circ
u
it
- Protection : Thi
s
circ
u
it comp
a
re
s
Vref
a
nd e
a
ch volt
a
ge
us
ing
comp
a
r
a
tor
- Interf
a
ce : DC/DC circ
u
it which i
s
connected with
Photo-co
u
pler,
S
CR
- Reporting : LED(Green) light on
Protection circ
u
it
b
eh
a
vior
s
- En
ab
le Circ
u
it : Thi
s
circ
u
it en
ab
le
s
protection circ
u
it
us
ing
Verc volt
a
ge
- En
ab
le : (High, Verc>
ab
o
u
t 60V)
- Volt
a
ge
s
en
s
ing : Verc, V
s
cl, V
s
ch volt
a
ge
s
en
s
ing
Verc>1
3
0V(Norm
a
l 100V)
V
s
cl>-165V(Norm
a
l -190V)
V
s
ch<-100V(Norm
a
l -70V)
- E
a
ch comp
a
r
a
tor en
ab
le
s
the protection circ
u
it if
a
ny volt
a
ge
i
s
ab
norm
a
l
b
ec
aus
e thi
s
con
s
i
s
t
s
with AND Logic
- If
S
CR i
s
en
ab
le DC/DC Controller(MR4710) F/B volt
a
ge i
s
low(0.7V)
a
nd V
s
cl, V
s
ch, Vccf volt
a
ge i
s
0 level.
-
Ypn, Y
s
c, Yfr,
S
c
a
n I.C
’s
b
eh
a
vior
s
s
top
s
a
nd no di
s
pl
a
y
-
Protection reporting thro
u
gh LED lighting
The Protection Y o
u
t
The norm
a
l Y o
u
t
