Integrated circuits, Transistor, Semiconductors Free Datasheet Search and Download Site


AD8032ANZ 데이터 시트보기 (PDF) - Analog Devices

부품명AD8032ANZ ADI
Analog Devices ADI
상세내역2.7 V, 800 μA, 80 MHz Rail-to-Rail I/O Amplifiers


AD8032ANZ Datasheet PDF : 20 Pages
First Prev 11 12 13 14 15 16 17 18 19 20
AD8031/AD8032
APPLICATIONS
A 2 MHz SINGLE-SUPPLY, BIQUAD BAND-PASS
FILTER
Figure 47 shows a circuit for a single-supply, biquad band-pass
filter with a center frequency of 2 MHz. A 2.5 V bias level is
easily created by connecting the noninverting inputs of all three
op amps to a resistor divider consisting of two 1 kΩ resistors
connected between 5 V and ground. This bias point is also
decoupled to ground with a 0.1 μF capacitor. The frequency
response of the filter is shown in Figure 48.
To maintain an accurate center frequency, it is essential that the
op amp have sufficient loop gain at 2 MHz. This requires the
choice of an op amp with a significantly higher unity gain,
crossover frequency. The unity gain, crossover frequency of the
AD8031/AD8032 is 40 MHz. Multiplying the open-loop gain by
the feedback factors of the individual op amp circuits yields the
loop gain for each gain stage. From the feedback networks of
the individual op amp circuits, it can be seen that each op amp
has a loop gain of at least 21 dB. This level is high enough to
ensure that the center frequency of the filter is not affected by
the op amp’s bandwidth. If, for example, an op amp with a gain
bandwidth product of 10 MHz was chosen in this application,
the resulting center frequency would shift by 20% to 1.6 MHz.
C1
50pF
R2
2k
R1
3k
VIN
1k
5V
0.1µF
R3
2k
AD8031
0.1µF
1k
R6
1k
R4
2k
5V
0.1µF
R5
2k
1/2
AD8032
C2
50pF
1/2
AD8032
VOUT
Figure 47. A 2 MHz, Biquad Band-Pass Filter Using AD8031/AD8032
0
–10
–20
–30
–40
–50
10k
100k
1M
10M
100M
FREQUENCY (Hz)
Figure 48. Frequency Response of 2 MHz Band-Pass Filter
HIGH PERFORMANCE, SINGLE-SUPPLY LINE DRIVER
Even though the AD8031/AD8032 swing close to both rails, the
AD8031 has optimum distortion performance when the signal
has a common-mode level half way between the supplies and
when there is about 500 mV of headroom to each rail. If low
distortion is required in single-supply applications for signals
that swing close to ground, an emitter-follower circuit can be
used at the op amp output.
5V
10µF
0.1µF
VIN
37
6
49.92
2N3904
4 AD8031
2.49k
2.49k
49.9
200
VOUT
49.9
Figure 49. Low Distortion Line Driver for Single-Supply, Ground Referenced Signals
Figure 49 shows the AD8031 configured as a single-supply, gain-
of-2 line driver. With the output driving a back-terminated
50 Ω line, the overall gain from VIN to VOUT is unity. In addition
to minimizing reflections, the 50 Ω back termination resistor
protects the transistor from damage if the cable is short circuited.
The emitter follower, which is inside the feedback loop, ensures
that the output voltage from the AD8031 stays about 700 mV
above ground. Using this circuit, low distortion is attainable
even when the output signal swings to within 50 mV of ground.
The circuit was tested at 500 kHz and 2 MHz.
Rev. C | Page 16 of 20
Direct download click here
HOME 'AD8032ANZ' Search

FEATURES
Low power
   Supply current 800 μA/amplifier
   Fully specified at +2.7 V, +5 V, and ±5 V supplies
High speed and fast settling on 5 V
   80 MHz, −3 dB bandwidth (G = +1)
   30 V/μs slew rate
   125 ns settling time to 0.1%
Rail-to-rail input and output
   No phase reversal with input 0.5 V beyond supplies
   Input CMVR extends beyond rails by 200 mV
   Output swing to within 20 mV of either rail
Low distortion
   −62 dB @ 1 MHz, VO= 2 V p-p
   −86 dB @ 100 kHz, VO= 4.6 V p-p
Output current: 15 mA
High grade option: VOS(maximum) = 1.5 mV

Share Link : 

English   日本語     русский     简体中文     español
@ 2015 - 2018  [ Home  ] [ Privacy Policy ] [ Request Datasheet  ] [ Contact Us ]