OPA361-Q1 Datasheet, PDF (7/18 Pages) Texas Instruments – 3V Video Amplifier with Internal Gain and Filter in SC70

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APPLICATION INFORMATION
OPA361-Q1
SBOS552 – MARCH 2011
The OPA361-Q1 video amplifier has been optimized to fit seamlessly with Texas Instruments’ OMAP242x
Multimedia processor. The following features have been integrated to provide excellent video performance.
• Internal gain setting resistors (G = 5.2V/V) reduce the number of external components needed in the video
circuit.
• Integration of the 500Ω video encoder load resistor and 4kΩ RSET resistor used by the OMAP242x helps
minimize the number of external components and also ensures excellent ratio and temperature tracking. This
feature helps to keep the overall gain accurate and stable over temperature.
• TV-detection support in connection with an OMAP242x multimedia processor. This feature helps to automate
start/stop operation of the TV-out function and minimizes power consumption.
• A 2-pole filter is incorporated for DAC signal reconstruction.
• The OPA361-Q1 employs an internal level shift circuit that avoids sync pulse clipping and allows DC-coupled
output.
• A shutdown feature reduces quiescent current to less than 1.5µA—crucial for portable applications
Although OPA361-Q1 is optimized for the OMAP242x processor, it is also suitable to interface with any digital
media processor that outputs a video signal on the order of 0.4V_PP to 0.5V_PP.
Figure 1 shows a typical application drawing with the OMAP242x processor and the TWL92230 Energy
Management Chip.
TWL92230
1.8V DAC
0.5V V_REF
OMAP2420
OPA361
Video
DAC
+In
500Ω
Regulator V_AUX
V+ 2.8V
2-Pole
Filte r
10mV
R_SET
TV Detect
GPIO ⁽³⁾
Enable
TV Detect
GPIO
4kΩ
Shutdown
Control
G =5.2V/V
(see note 1)
GND
100kΩ⁽²⁾
1.8V
Out ^75Ω
PullUp
10kΩ
+
75Ω
Figure 1. Typical Application using the OMAP242x and the TWL92230
Copyright © 2011, Texas Instruments Incorporated
Product Folder Link(s) :OPA361-Q1
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