EL2210 INTERSIL [Intersil Corporation], EL2210 Datasheet - Page 7

• Manufacturer Part Number: EL2210
• Description: Low Cost, Dual, Triple and Quad Video Op Amps
• Manufacturer: INTERSIL [Intersil Corporation]

expected ambient temperature of 85°C, the total allowable
power dissipation for the SO8 package would be:
At 12V total supply voltage each amplifier draws a maximum
of 10mA and dissipates 12V * 10mA = 120mW or 240mW for
the dual amplifier. Which leaves 121mW of increased power
due to the load. If the load were 150Ω connected to the most
negative voltage and the maximum voltage out were V
+1V the load current would be 6.67mA. Then an extra
146mW ((12V - 1V) * 6.67mA * 2) would be dissipated in the
EL2210 or EL2211. The total dual amplifier power
dissipation would be 146mW + 240mW = 386mW, more than
the maximum 361mW allowed. If the total supply difference
were reduced to 10V, the same calculations would yield
200mW quiescent power dissipation and 120mW due to
loading. This results in a die temperature of 143°C (85°C +
58°C).
In the above example, if the supplies were split ±6V and the
150Ω loads were connected to ground, the load induced
power dissipation would drop to 66.7mW (6.67mA * (6 - 1) *
2) and the die temperature would be below the rated
maximum.
Video Performance
Following industry standard practices (see EL2044
applications section) these six devices exhibit good
differential gain (dG) and good differential phase (dP) with
±5V supplies and an external 820Ω resistor to the negative
supply, in a gain of 2 configuration. Driving 75Ω back
terminated cables to standard video levels (1.428V at the
amplifier) the EL2210, EL2310, and EL2410 have dG of
0.1% and dP of 0.2°. The EL2211, EL2311, and EL2411
have dG of 0.04% and dP of 0.15°.
P
D
=
-------------------------
160°C/W
150 85
–
7
=
361mW
EL2210/11, EL2310/11, EL2410/11
S
-
Due to the negative swing limitations described above,
inverted video at a gain of 2 is just not practical. If swings
below ground are required then changing the extra 820Ω
resistor to 500Ω will allow reasonable dG and dP to
approximately -0.75mV. The EL2211, EL2311, and EL2411
will achieve approximately 0.1%/0.4° between 0V and
-0.75V. Beyond -0.75V dG and dP get worse by orders of
magnitude.
Differential gain and differential phase are fairly constant for
all loads above 150Ω. Differential phase performance will
improve by a factor of 3 if the supply voltage is increased to
±6V.
Output Drive Capability
None of these devices have short circuit protection. Each
output is capable of more than 100mA into a shorted output.
Care must be used in the design to limit the output current
with a series resistor.
Printed-Circuit Layout
The EL2210/EL2211/EL2310/EL2311/ EL2410/EL2411 are
well behaved, and easy to apply in most applications.
However, a few simple techniques will help assure rapid,
high quality results. As with any high-frequency device, good
PCB layout is necessary for optimum performance. Ground-
plane construction is highly recommended, as is good power
supply bypassing. A 0.1µF ceramic capacitor is
recommended for bypassing both supplies. Lead lengths
should be as short as possible, and bypass capacitors
should be as close to the device pins as possible. For good
AC performance, parasitic capacitances should be kept to a
minimum at both inputs and at the output. Resistor values
should be kept under 5kΩ because of the RC time constants
associated with the parasitic capacitance. Metal-film and
carbon resistors are both acceptable, use of wire-wound
resistors is not recommended because of their parasitic
inductance. Similarly, capacitors should be low-inductance
for best performance.