MAX4477AUA-T Maxim Integrated, MAX4477AUA-T Datasheet - Page 9

• Manufacturer Part Number: MAX4477AUA-T
• Description: Operational Amplifiers - Op Amps Wide-Band Rail-Rail
• Manufacturer: Maxim Integrated

Specifications of MAX4477AUA-T

• Number Of Channels: 2
• Common Mode Rejection Ratio (min): 90 dB
• Input Offset Voltage: 350 uV
• Input Bias Current (max): 150 pA
• Operating Supply Voltage: 2.7 V to 5.5 V
• Mounting Style: SMD/SMT
• Package / Case: uMAX-8
• Slew Rate: 3 V/us
• Shutdown: No
• Output Current: 48 mA
• Maximum Operating Temperature: + 125 C
• Amplifier Type: Low Noise Amplifier
• Gain Bandwidth Product: 10 MHz
• Minimum Operating Temperature: - 40 C
• Supply Current: 2.2 mA
• Technology: BiCMOS
• Voltage Gain Db: 120 dB

The MAX4475–MAX4478/MAX4488/MAX4489 single-
supply operational amplifiers feature ultra-low noise
and distortion. Their low distortion and low noise make
them ideal for use as preamplifiers in wide dynamic-
range applications, such as 16-bit analog-to-digital
converters (see Typical Operating Circuit ). Their high-
input impedance and low noise are also useful for sig-
nal conditioning of high-impedance sources, such as
piezoelectric transducers.
These devices have true rail-to-rail ouput operation,
drive loads as low as 1kΩ while maintining DC accura-
cy, and can drive capactive loads up to 200pF without
oscillation. The input common-mode voltage range
extends from (V
rail. The push-pull output stage maintains excellent DC
characteristics, while delivering up to ±5mA of current.
The MAX4475–MAX4478 are unity-gain stable, while
the MAX4488/MAX4489 have a higher slew rate and
are stable for gains ≥ 5V/V. The MAX4475/MAX4488
feature a low-power shutdown mode, which reduces
the supply current to 0.01µA and disables the outputs.
Many factors can affect the noise and distortion that the
device contributes to the input signal. The following
guidelines offer valuable information on the impact of
design choices on Total Harmonic Distortion (THD).
Choosing proper feedback and gain resistor values for
a particular application can be a very important factor
in reducing THD. In general, the smaller the closed-
loop gain, the smaller the THD generated, especially
when driving heavy resistive loads. The THD of the part
normally increases at approximately 20dB per decade,
as a function of frequency. Operating the device near
or above the full-power bandwidth significantly
degrades distortion.
Referencing the load to either supply also improves the
part’s distortion performance, because only one of the
MOSFETs of the push-pull output stage drives the out-
put. Referencing the load to midsupply increases the
part’s distortion for a given load and feedback setting.
(See the Total Harmonic Distortion vs. Frequency graph
in the Typical Operating Characteristics .)
For gains ≥ 5V/V, the decompensated devices
MAX4488/MAX4489 deliver the best distortion perfor-
mance, since they have a higher slew rate and provide
a higher amount of loop gain for a given closed-loop
gain setting. Capacitive loads below 100pF do not sig-
nificantly affect distortion results. Distortion perfor-
mance is relatively constant over supply voltages.
Maxim Integrated
DD
MAX4475–MAX4478/MAX4488/MAX4489
- 1.6V) to 200mV below the negative
Detailed Description
SOT23, Low-Noise, Low-Distortion,
Low Distortion
Wide-Band, Rail-to-Rail Op Amps
Figure 1. Adding Feed-Forward Compensation
Figure 2a. Pulse Response with No Feed-Forward
Compensation
Figure 2b. Pulse Response with 10pF Feed-Forward
Compensation
100mV
0V
R
G
A
R
A
R
V
F
V
F
= R
= +2
= R
= +2
G
G
= 100kΩ
= 100kΩ
V
IN
2µs/div
2µs/div
R
F
C
Z
V
100mV/div
V
100mV/div
V
100mV/div
V
100mV/div
IN
OUT
IN
OUT
V
OUT
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