MC33077 Motorola, MC33077 Datasheet - Page 10

• Manufacturer Part Number: MC33077
• Description: LOW NOISE OPERATIONAL AMPLIFIER
• Manufacturer: Motorola

offset voltage, high gain bandwidth product and large output
swing characteristics. Its outstanding high frequency
gain/phase performance make it a very attractive amplifier for
high quality preamps, instrumentation amps, active filters
and other applications requiring precision quality
characteristics.
transistors in a low noise bipolar differential stage driving a
compensated Miller integration amplifier. Dual–doublet
frequency compensation techniques are used to enhance the
gain bandwidth product. The output stage uses an all NPN
transistor design which provides greater output voltage swing
and improved frequency performance over more
conventional stages by using both PNP and NPN transistors
(Class AB). This combination produces an amplifier with
superior characteristics.
current mirror design, a lower than normal temperature
coefficient of input offset voltage (2.0 V/ C as opposed to 10
below the positive rail (V CC ) to 1.5 V above the negative rail
(V EE ). The inputs will typically common mode to within 1.0 V
of both negative and positive rails though degradation in
offset voltage and gain will be experienced as the common
mode voltage nears either supply rail. In practice, though not
recommended, the input voltage may exceed V CC by
approximately 30 V and decrease below the V EE by
approximately 0.6 V without causing permanent damage to
the device. If the input voltage on either or both inputs is less
than approximately 0.6 V, excessive current may flow, if not
limited, causing permanent damage to the device.
20 mA, though in practice, source currents should be limited
to 5.0 mA to avoid any parametric damage to the device. If
both inputs exceed V CC , the output will be in the high state
and phase reversal may occur. No phase reversal will occur
if the voltage on one input is within the common mode range
and the voltage on the other input exceeds V CC . Phase
reversal may occur if the input voltage on either or both inputs
is less than 1.0 V above the negative rail. Phase reversal will
be experienced if the voltage on either or both inputs is less
than V EE .
techniques, the gain bandwidth product has been greatly
enhanced over other amplifiers using the conventional single
pole compensation. The phase and gain error of the amplifier
remains low to higher frequencies for fixed amplifier gain
configurations.
V/ C), as well as low input offset voltage, is accomplished.
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The MC33077 is designed primarily for its low noise, low
The MC33077 utilizes high frequency lateral PNP input
Through precision component matching and innovative
The minimum common mode input range is from 1.5 V
The amplifier will not latch with input source currents up to
Through the use of dual–doublet frequency compensation
APPLICATIONS INFORMATION
MC33077
to the supply rails, producing superior output swing, no
crossover distortion and improved output phase symmetry
with output voltage excursions (output phase symmetry
being the amplifiers ability to maintain a constant phase
relation independent of its output voltage swing). Output
phase symmetry degradation in the more conventional PNP
and NPN transistor output stage was primarily due to the
inherent cut–off frequency mismatch of the PNP and NPN
transistors used (typically 10 MHz and 300 MHz,
respectively), causing considerable phase change to occur
as the output voltage changes. By eliminating the PNP in the
output, such phase change has been avoided and a very
significant improvement in output phase symmetry as well as
output swing has been accomplished.
operation is with lower supply voltages (typically 30% with
can typically swing to within 1.0 V of the positive rail (V CC ),
and to within 0.3 V of the negative rail (V EE ), producing a 28.7
V pp signal from 15 V supplies. Output voltage swing can be
further improved by using an output pull–up resistor
referenced to the V CC . Where output signals are referenced
to the positive supply rail, the pull–up resistor will pull the
output to V CC during the positive swing, and during the
negative swing, the NPN output transistor collector will pull
the output very near V EE . This configuration will produce the
maximum attainable output signal from given supply
voltages. The value of load resistance used should be much
less than any feedback resistance to avoid excess loading
and allow easy pull–up of the output.
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frequency (see Figure 18). The amplifier is unity gain stable
with output capacitance loads up to 500 pF at full output
swing over the –55 to +125 C temperature range. Output
phase symmetry is excellent with typically 4 C total phase
change over a 20 V output excursion at 25 C with a 2.0 k
and 100 pF load. With a 2.0 k
capacitance loading, the total phase change is approximately
one degree for the same 20 V output excursion. With a
2.0 k and 500 pF load at 125 C, the total phase change is
typically only 10 C for a 20 V output excursion (see Figure
27).
that one does not create a pole at the input of the amplifier
which is near the closed loop corner frequency. This
becomes a greater concern when using high frequency
amplifiers since it is very easy to create such a pole with
relatively small values of resistance on the inputs. If this does
5.0 V supplies). With a 10 k load, the output of the amplifier
With the all NPN output stage, there is minimal swing loss
The output swing improvement is most noticeable when
Output impedance of the amplifier is typically less than
As with all amplifiers, care should be exercised to insure
at frequencies less than the unity gain crossover
MOTOROLA ANALOG IC DEVICE DATA
resistive load and no