EL5244CN View Datasheet(PDF) - Elantec -> Intersil
Part Name
Description
Manufacturer
EL5244CN Datasheet PDF : 20 Pages
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EL5144C, EL5146C, EL5244C, EL5246C,
EL5444C
100 MHz Single Supply Rail to Rail Amplifier
loss which may be created by this additional resistor at
the output. Another method of reducing peaking is to
add a “snubber” circuit at the output. A snubber is a
resistor in a series with a capacitor, 150Ω and 100pF
being typical values. The advantage of a snubber is that
it does not draw DC load current.
When used as a cable driver, double termination is
always recommended for reflection-free performance.
For those applications, the back-termination series resis-
tor will de-couple the EL5144C series amplifier from the
cable and allow extensive capacitive drive. However,
other applications may have high capacitive loads with-
out a back-termination resistor. Again, a small series
resistor at the output can reduce peaking.
Disable / Power-Down
The EL5146C and EL5246C amplifiers can be disabled,
placing its output in a high-impedance state. Turn off
time is only 10 nsec and turn on time is around 500 nsec.
When disabled, the amplifier’s supply current is reduced
to 2.6µA typically, thereby effectively eliminating
power consumption. The amplifier’s power down can be
controlled by standard TTL or CMOS signal levels at the
CE pin. The applied logic signal is relative to the GND
pin. Letting the CE pin float will enable the amplifier.
Hence, the 8 pin PDIP and SOIC single amps are pin
compatible with standard amplifiers that don’t have a
power down feature.
Short Circuit Current Limit
The EL5144C series amplifiers do not have internal
short circuit protection circuitry. Short circuit current of
90 mA sourcing and 65 mA sinking typically will flow if
the output is trying to drive high or low but is shorted to
half way between the rails. If an output is shorted indef-
initely, the power dissipation could easily increase such
that the part will be destroyed. Maximum reliability is
maintained if the output current never exceeds ±50mA.
This limit is set by internal metal interconnect limita-
tions. Obviously, short circuit conditions must not
remain or the internal metal connections will be
destroyed.
Power Dissipation
With the high output drive capability of the EL5144C
series amplifiers, it is possible to exceed the 150°C
Absolute Maximum junction temperature under certain
load current conditions. Therefore, it is important to cal-
culate the maximum junction temperature for the
application to determine if load conditions or package
type need to be modified for the amplifier to remain in
the safe operating area.
The maximum power dissipation allowed in a package is
determined according to:
PDMAX= T----J---M-----A----X--Θ---–--J--A-T----A----M-----A----X--
where:
TJMAX = Maximum Junction Temperature
TAMAX = Maximum Ambient Temperature
θJA = Thermal Resistance of the Package
PDMAX = Maximum Power Dissipation
in the Package.
The maximum power dissipation actually produced by
an IC is the total quiescent supply current times the total
power supply voltage, plus the power in the IC due to the
load, or:
PDMAX=
N • VS • ISMAX + (V S – VOUT ) •
V-----RO----LU----T--
where:
N = Number of amplifiers in the package
VS = Total Supply Voltage
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