Low Distortion, High Speed
Rail-to-Rail Input/Output Amplifiers
AD8027/AD8028
CONNECTION DIAGRAMS
FEATURES
High speed
190 MHz, –3 dB bandwidth (G = +1)
100 V/μs slew rate
Low distortion
120 dBc @ 1 MHz SFDR
80 dBc @ 5 MHz SFDR
AD8027
SOIC-8
(R)
AD8027
SOT-23-6
(RT)
NC
–IN
+IN
1
2
3
4
8
7
6
5
V
1
2
6
5
4
+V
S
DISABLE/SELECT
OUT
+V
V
S
–V
S
DISABLE/SELECT
–IN
OUT
+
–
–V
NC
S
+IN
3
NC = NO CONNECT
Selectable input crossover threshold
Low noise
AD8028
SOIC-8
(R)
AD8028
MSOP-10
(RM)
V
1
2
3
4
8
7
6
5
V
1
2
3
4
5
10
9
+V
V
+V
V
4.3 nV/√Hz
1.6 pA/√Hz
OUTA
OUTA
S
S
–
+
–IN A
+IN A
–IN A
–
+
OUTB
–IN B
OUTB
–IN B
–
+
+IN A
–
8
Low offset voltage: 900 μV max
Low power: 6.5 mA/amplifier supply current
Power-down mode
No phase reversal: VIN > |VS| + 200 mV
Wide supply range: 2.7 V to 12 V
Small packaging: SOIC-8, SOT-23-6, MSOP-10
+
–V
+IN B
–V
7
+IN B
S
S
6
DISABLE/SELECT A
DISABLE/SELECT B
03327-B-001
Figure 1. Connection Diagrams (Top View)
With their wide supply voltage range (2.7 V to 12 V) and wide
bandwidth (190 MHz), the AD8027/AD8028 amplifiers are
designed to work in a variety of applications where speed and
performance are needed on low supply voltages. The high per-
formance of the AD8027/AD8028 is achieved with a quiescent
current of only 6.5 mA/amplifier typical. The AD8027/AD8028
have a shutdown mode that is controlled via the SELECT pin.
APPLICATIONS
Filters
ADC drivers
Level shifting
Buffering
Professional video
Low voltage instrumentation
The AD8027/AD8028 are available in SOIC-8, MSOP-10, and
SOT-23-6 packages. They are rated to work over the industrial
temperature range of –40°C to +125°C.
GENERAL DESCRIPTION
The AD8027/AD80281 are high speed amplifiers with rail-to-
rail input and output that operate on low supply voltages and
are optimized for high performance and wide dynamic signal
range. The AD8027/AD8028 have low noise (4.3 nV/√Hz,
1.6 pA/√Hz) and low distortion (120 dBc at 1 MHz). In appli-
cations that use a fraction of, or the entire input dynamic range
and require low distortion, the AD8027/AD8028 are ideal
choices.
–20
G = +1
FREQUENCY = 100kHz
R
= 1kΩ
L
–40
–60
V
= +5V
S
V
= +3V
S
V
= ±5V
S
–80
–100
–120
–140
Many rail-to-rail input amplifiers have an input stage that
switches from one differential pair to another as the input signal
crosses a threshold voltage, which causes distortion. The
AD8027/AD8028 have a unique feature that allows the user to
select the input crossover threshold voltage through the
SELECT pin. This feature controls the voltage at which the
complementary transistor input pairs switch. The AD8027/
AD8028 also have intrinsically low crossover distortion.
0
1
2
3
4
5
6
7
8
9
10
OUTPUT VOLTAGE (V p-p)
03327-A-063
Figure 2. SFDR vs. Output Amplitude
1Protected by U.S. patent numbers 6,486,737B1; 6,518,842B1
Rev. C
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