Datasheet
17
20
19
18
16
15
11
14
13
12
DAC/
Encoder
3.3V
1
2
3
4
5
6
7
8
9
10
Y’
S-Video
Y’
S-Video
C’
CBVS
P’
B
P’
R
75 W
75 W
75 W
75 W
75 W
750 W
750 W
750 W
2.2pF
2.2pF
2.2pF
75 W
0.01 Fm
33 Fm
R
R
R
R
R
R
Video
Out1
Video
Out2
Video
Out3
+
3.3V
I C
Controller
2
DC+250mV
DC+250mV
DC+250mV
DC+250mV
DC+250mV
DC+250mV
GND
CH.2 IN B
CH.3 IN B
I2C-A0
I2C-SDA
V
S+
I2C-SCLI2C-A1
CH.1 IN B
CH.2 IN A
CH.3 IN A
CH.1 IN A
NC
CH.3 OUT
CH.2 OUT
CH1.
GAIN ADJ
CH2.
GAIN ADJ
CH3.
GAIN ADJ
CH.1 OUT
NC
THS7353
SLOS484B –NOVEMBER 2005–REVISED AUGUST 2012
www.ti.com
The I
2
C interface of the THS7353 allows each channel to be configured totally independent of the other
channels. One of the benefits is that a multiple output encoder (or DAC) can be routed through one THS7353
with the proper input configuration and low-pass filter required regardless of the signal. This is useful for a
portable system or in a low cost system where only one set (or two sets in parallel) is desired on the output of
the system. An update of the I
2
C commands changes the THS7353 channels. An example is shown in Figure 68
where the input MUX allows for one set of HDTV signals to be put into the THS7353, and then through an I
2
C
update, a SDTV set of signals is sent through the THS7353 with the proper input mode and low-pass filters.
Figure 68. Typical EDTV/HDTV and SDTV Encoder DAC Driving a Single THS7353
Although the circuit of Figure 68 conserves space and cost, the re-use of the output connections may not be the
best solution. For a complete system, the THS7353 can be used as an input buffer and the THS7313 (SLOS483)
and THS7303 (SLOS479) are used as output buffers as shown in Figure 69. The THS7313 is targeted for SDTV
signals and is limited to an 8-MHz filter. The THS7303 is a selectable SD/ED/HD line driver buffer. As the I
2
C
section discusses, it is easy to have both parts in one system as the I
2
C address of each part can be one of four
discrete addresses by the logic appearing on the I
2
C-A1 and I
2
C-A0 lines.
32 Copyright © 2005–2012, Texas Instruments Incorporated