IC,ANALOG MUX,TRIPLE,2-CHANNEL,BIPOLAR,TSSOP,24PIN,PLASTIC

AD8186ARUZ

Manufacturer Part NumberAD8186ARUZ
DescriptionIC,ANALOG MUX,TRIPLE,2-CHANNEL,BIPOLAR,TSSOP,24PIN,PLASTIC
ManufacturerAnalog Devices Inc
TypeAnalog Multiplexer
AD8186ARUZ datasheet
 


Specifications of AD8186ARUZ

Rohs CompliantYESFunctionMultiplexer
Circuit3 x 2:1On-state Resistance350 mOhm
Voltage Supply SourceSingle SupplyVoltage - Supply, Single/dual (±)3.5 V ~ 5.5 V
Current - Supply15mAOperating Temperature-40°C ~ 85°C
Mounting TypeSurface MountPackage / Case24-TSSOP (0.173", 4.40mm Width)
Package24TSSOPMultiplexer Architecture2:1
Maximum Turn-off Time17(Typ)@5V nsMaximum Turn-on Time4(Typ)@5V ns
Power Supply TypeSingleLead Free Status / RoHS StatusLead free / RoHS Compliant
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APPLICATION
Single-Supply Operation
The AD8186/AD8187 are targeted mainly for use in single-
supply 5 V systems. For operating on these supplies, both V
and D
should be tied to ground. The control logic pins will
GND
be referenced to ground. Normally, the DV
set to the same positive supply as the driving logic.
For dc-coupled single-supply operation, it is necessary to set an
appropriate input dc level that is within the specified range of the
amplifier. For the unity-gain AD8186, the output dc level will
be the same as the input, while for the gain-of-two AD8187, the
V
input can be biased to obtain an appropriate output dc level.
REF
Figure 10 shows a circuit that provides a gain-of-two and is
dc-coupled. The video input signals must have a dc bias
from their source of approximately 1.5 V. This same volt-
age is applied to V
of the AD8187. The result is that when
REF
the video signal is at 1.5 V, the output will also be at the
same voltage. This is close to the lower dynamic range of
both the input and the output.
When the input goes most positive, which is 700 mV above the
black level for a standard video signal, it reaches a value of 2.2 V
and there is enough headroom for the signal. On the output
side, the magnitude of the signal will change by 1.4 V, which
will make the maximum output voltage 2.2 V + 1.4 V = 3.6 V.
This is just within the dynamic range of the output of the part.
AC Coupling
When a video signal is ac-coupled, the amount of dynamic range
required to handle the signal can potentially be double that
required for dc-coupled operation. For the unity-gain AD8186,
0.7V MAX
2.2V
1.5V
BLACK
LEVEL
TYPICAL INPUT LEVELS
(ALL 6 OUTPUTS)
Figure 10. DC-Coupled (Bypassing and Logic Not Shown)
REV. A
there is still enough dynamic range to handle an ac-coupled,
standard video signal with 700 mV p-p amplitude.
If the input is biased at 2.5 V dc, the input signal can potentially go
EE
700 mV both above and below this point. The resulting 1.8 V and
2.2 V are within the input signal range for single 5 V operation.
supply should be
CC
Since the part is unity-gain, the outputs will follow the inputs,
and there will be adequate range at the output as well.
When using the gain-of-two AD8187 in a simple ac-coupled
application, there will be a dynamic range limitation at the output
caused by its higher gain. At the output, the gain-of-two will
produce a signal swing of 1.4 V, but the ac coupling will double
this required amount to 2.8 V. The AD8187 outputs can only
swing from 1.4 V to 3.6 V on a 5 V supply, so there are only
2.2 V of dynamic signal swing available at the output.
A standard means for reducing the dynamic range requirements
of an ac-coupled video signal is to use a dc restore. This circuit
works to limit the dynamic range requirements by clamping the
black level of the video signal to a fixed level at the input to the
amplifier. This prevents the video content of the signal from
varying the black level as happens in a simple ac-coupled circuit.
After ac coupling a video signal, it is always necessary to use a
dc restore to establish where the black level is. Usually, this
appears at the end of a video signal chain. This dc restore circuit
needs to have the required accuracy for the system. It compen-
sates for all the offsets of the preceding stages. Therefore, if a
dc restore circuit is to be used only for dynamic-range limiting,
it does not require great dc accuracy.
3V TO 5V
5V
DV
V
IN0A
CC
CC
AD8187
REDA
IN1A
OUT0
GRNA
2
IN2A
BLUA
5V
3.48k
OUT1
1.5V
2
V
REF
1.5k
IN0B
OUT2
REDB
2
IN1B
GRNB
IN2B
BLUB
D
V
OE
SEL A/B
GND
EE
–15–
AD8186/AD8187
RED
3.0V
1.4V MAX
1.5V
GRN
BLACK
LEVEL
TYPICAL OUTPUT LEVELS
(ALL 3 OUTPUTS)
BLU