lt6559cud-trpbf Linear Technology Corporation, lt6559cud-trpbf Datasheet - Page 12
lt6559cud-trpbf
Manufacturer Part Number
lt6559cud-trpbf
Description
Low Cost 5v/?5v 300mhz Triple Video Amplifier In 3mm X 3mm Qfn
Manufacturer
Linear Technology Corporation
Datasheet
1.LT6559CUD-TRPBF.pdf
(16 pages)
TYPICAL APPLICATIONS
LT6559
YP
Two LT6559s can be used to map the YP
video into the RGB color space as shown in Figure 8. The
Y input is properly terminated with 75Ω and buffered with
a gain of 2 by amplifi er A2. The P
and buffered with a gain of 2.8 by amplifi er A1. The P
input is terminated and buffered with a gain of 3.6 by
amplifi er A3.
Amplifi er B1 performs an equally weighted addition
of amplifi ers A1 and A2 outputs, thereby producing
2(Y + 1.4P
terminated load due to the voltage division by 2 caused by
the termination resistors. Amplifi er B3 forms the equally
weighted addition of amplifi ers A2 and A3 outputs, thereby
producing 2(Y + 1.8P
signal at the terminated load.
12
B
P
R
to RGB Conversion
R
), which generates the desired R signal at the
P
P
R
B
Y
165Ω
301Ω
118Ω
B
), which generates the desired B
75Ω
75Ω
75Ω
–
1/3 LT6559
+
–
1/3 LT6559
+
–
1/3 LT6559
+
A1
A2
A3
R
301Ω
301Ω
301Ω
input is terminated
B
P
R
“component”
Figure 8. YP
B
P
1.54k
698Ω
B
1k
1k
1k
1k
R
to RGB Conversion
Amplifi er B2 performs a weighted summation of all three
inputs. The P
The P
Therefore the amplifi er B2 output is:
which generates the desired G signal at the terminated load.
The sync present on the Y input is reconstructed on all
three R, G, and B outputs.
The Y signal is amplifi ed overall by:
301Ω
590Ω
1k
2(Y – 0.34P
301Ω
1 54
1
−
−
590
6559 F08
k
.
301
301
R
+
1
signal is amplifi ed overall by:
k
698
k
• .
• .
2 8 2 0 71
3 6 2 0 34
–
1/3 LT6559
+
–
1/3 LT6559
+
–
1/3 LT6559
+
•
B
B1
B2
B3
1
B
signal is amplifi ed overall by:
= −
= −
+
301Ω
301Ω
301Ω
– 0.71P
590 1 54
(
(
. )
301
|| .
.
R
R = Y + 1.40P
G = Y – 0.34P
B = Y + 1.77P
ALL RESISTORS 1%
V
)
S
)
= ±3V TO ±5V
k
75Ω
75Ω
75Ω
•
2 2 1
B
R
B
=
– 0.71 P
( )
R
G
B
R
6559f