Philips pm2521 - Page 128

136
SAA1062
LCD DISPLAY/INTERFACE
CIRCUIT
GENERAL
DESCRIPTION
The
SAA1062 is designed
to drive
a
Liquid
Crystal Display
(LCD)
of
a
digital
tuning system. It contains
a shift
register
with programmable
length
(18
or 21 bits),
latches, both synchronized or static,
exclusive-OR segment
drivers
(17
or 20 bits), an l.f.
oscillator and
a backplane driver
for
the
LCD. The circuit is designed
to be driven
by a 3 bus structure from
a microprocessor
and
can
also
be used
as
a programmable
17 or 20 bits serial-to
parallel decoder.
It is
also
capable
of storing
60
bits
of information.
DLEN
DATA
LEADING ZERO
)
o^cxx:iiiJir]aacocxxxDe^^^
LOAD ENABLE CLOCK PULSEj
SIGNIFICANT
DATA
CLB
BIT NUMBER
OUTPUT
BIT
NUMBER
OUTPUT
20 19
18 17
16 15 14
13 12 11
10 9 8 7
6
5 4 3
2
1
°20
'^IS
°18
Qi7
°16
Qi5
Ol4
°13
Qi2
On
OlO
O
9
08 Q
^
Q
g
“5
O
4
O
3
D
2
O'
17 16
15 14
13 12 11
9 8 7
6 5
4
3 2
1
0
17
0
16
Q
15
Q
14
°13
Q
12
0
10
s
°8
°5 °3 °2
0,
—
LOAD BIT
1 20BIT
/
S.R.
\
17BIT
/
S.R.
Organization
of 18
and 21
bits
words; DA TA
-
LOWmeans
segment
'on"
‘‘20
Q
19
I
0
18
Q,7
^16
Qi5
Qu
I
°
13
I Q 1
MO
i
i
Pinning
diagram