Datasheet

12.5pF
1kW
4.22kW
1838W 2.5kW
V
O
OPA362
( )
3.6pF
872W
75W
75W
Television
OPA362
www.ti.com ........................................................................................................................................................................................ SBOS480 –SEPTEMBER 2009
Operating Voltage Enable pin enables the op amp. The logic levels are
compatible with 1.8V CMOS logic levels. A valid logic
The OPA362 is fully specified from 2.5V to 3.3V over
high is defined as greater than 1.3V above GND. A
a temperature range of –40°C to +125°C. Parameters
valid logic low is defined as less than 0.5V above
that vary significantly with operating voltages or
GND. If the Enable pin is not connected, internal
temperature are shown in the Typical Characteristics.
pull-up circuitry enables the amplifier.
Power-supply pins should be bypassed with 100nF
ceramic capacitors. When disabling the OPA362, internal circuitry also
disconnects the internal gain setting feedback. This
feature supports the TV-detection function; see the
Input Voltage
TV-Detect Function section for more detailed
The input common-mode range of the OPA362 series
information.
extends from GND to 0.55V on a 3.3V supply. The
input range is limited by the internal gain in
Internal Two-Pole Filter
conjunction with the maximum output swing capability
and the power-supply voltage. The OPA362 filter is a Sallen-Key topology with an
8.5MHz cutoff frequency. Figure 19 shows a detailed
drawing of the filter components. This filter allows
Input Overvoltage Protection
video signals to pass without any visible distortion, as
All OPA362 pins are static-protected with internal
shown in Figure 20 through Figure 23. The video
ESD protection diodes connected to the supplies.
encoder embedded in the OMAP343x processor
These diodes provide input overdrive protection if the
typically samples at 54MHz. At this frequency, the
current is externally limited to 10mA.
attenuation is typically 23dB, which effectively
attenuates the sampling aliases.
Enable/Shutdown
The internal 872Ω resistor on the input to GND
The OPA362 has a shutdown feature that disables
converts the output current of the OMAP3430 internal
the output and reduces the quiescent current to less
video DAC into a voltage. It is also part of the
than 1.5μA. This feature is especially useful for
Sallen-Key filter. Using an external resistor to adjust
portable video applications, where the device is
the input voltage range also changes the filter
infrequently connected to a television (TV) or other
characteristics.
video device.
The Enable logic input voltage is referenced to the
OPA362 GND pin. A logic level high applied to the
Figure 19. OPA362 Filter Structure
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Product Folder Link(s): OPA362